Protected: Prognostic Factors of Peritonitis in Patients on Peritoneal Dialysis: a Retrospective Observational Study

Abstract

Background/Objectives. Peritoneal dialysis stands as an established form of renal replacement therapy; yet peritonitis remains a major complication associated with it. This study, analyzing two decades of data from the Nephrology, Dialysis, and Hypertension Division of the University-Hospital IRCCS in Bologna, aimed to identify prognostic factors linked to peritonitis events. It also sought to evaluate the suitability of different peritoneal dialysis techniques, with a focus on Automated Peritoneal Dialysis (APD) and Continuous Ambulatory Peritoneal Dialysis (CAPD). Additionally, the study assessed the impact of an educational program introduced in 2005 on peritonitis frequency.
Methods. Conducting an observational, retrospective, single-center study, 323 patients were included in the analysis, categorized based on their use of APD or CAPD.
Results. Despite widespread APD usage, no significant correlation was found between the dialysis technique (APD or CAPD) and peritonitis onset. The analysis of the educational program’s impact revealed no significant differences in peritonitis occurrence. However, a clear relationship emerged between regular patient monitoring at the reference center and the duration of peritoneal dialysis.
Conclusions. Despite the absence of a distinct association between peritonitis onset and dialysis technique, regular patient monitoring at the reference center significantly correlated with prolonged peritoneal dialysis duration.

Keywords: end-stage renal disease, peritoneal dialysis, peritonitis, peritoneal catheter

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Peritoneal Dialysis Network in North-East Italy: Survey About the Peritoneal Catheter Exit-Site Infection Management and Comparison with ISPD Guidelines

Abstract

Introduction. The Triveneto Peritoneal Dialysis (PD) Network aims to bring together doctors and nurses who deal with PD in a collaborative network in which to exchange mutual knowledge and optimize the use of this method of replacing renal function. A topic of particular interest was the management of peritoneal catheter exit-site infection, given the recent publication of the new guidelines of the International Society of Peritoneal Dialysis (ISPD).
Materials and methods. The survey concerned the criteria for carrying out nasal swab and exit-site, management of exuberant granulation tissue “Proud Flesh”, treatment of exit-site infection (ESI), use of silver dressings, the role of subcutaneous tunnel ultrasound and cuff shaving.
Results. All PD centers in the North-East Italy area have joined the survey with at least one operator per centre. There was a wide variability between the indications for performing the exit-site swab. In the presence of ESI, the prevalent approach is that of oral systemic empiric therapy associated (20.0%) or less (28.9%) with topical therapy, and then adapting it in a targeted manner to the culture examination.
Discussion. From the discussion of the survey emerged the importance of the ESI as an outcome indicator, which allows us to verify whether our clinical practice is in line with the reference standards. It is essential to know and base our activity on what is indicated in national and international guidelines and to document the events that occur in the patient population of each dialysis unit.

Keywords: Peritoneal Dialysis, Exit-site management, Catheter-related Infections, Survey

Sorry, this entry is only available in Italian.

Introduzione

La dialisi peritoneale (PD) è un importante trattamento dialitico domiciliare cui opta quasi un paziente su cinque fra gli afferenti agli ambulatori specialistici nefrologici [1]. Per i pazienti in PD le infezioni correlate al catetere peritoneale (CP) sono tra i principali fattori di rischio di peritoniti, perdita del CP, drop-out dalla metodica. Queste comprendono l’infezione dell’exit-site (ESI) e del tunnel del CP [2].

Il “Network di Dialisi Peritoneale del Triveneto” ha lo scopo di riunire medici e infermieri che si occupano di PD nel Triveneto per la costruzione di una rete collaborativa all’interno della quale sia possibile diffondere la conoscenza e ottimizzare l’impiego di questa metodica sostitutiva della funzione renale. In questi incontri si parte dall’analisi delle evidenze per quindi verificarne l’attuazione nella real life e confrontarle con l’esperienza e i risultati derivanti dalla pratica clinica dei centri dialisi del Triveneto.

Un argomento di particolare interesse è risultato essere la gestione dell’exit-site infetto del CP, soprattutto in considerazione della recente pubblicazione delle nuove linee guida della Società Internazionale di Dialisi Peritoneale (ISPD) [3]. 

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Cuff Shaving in Recurrent Exit-Site Infections in a Patient on Peritoneal Dialysis

Abstract

In patients on peritoneal dialysis, the cutaneous emergency (exit-site) represents a potential access route to the peritoneum; consequently, it can become a site for microbial infections. These infections, initially localized to the exit-site, may spread to the peritoneum causing peritonitis, which is the most common cause of drop-out from peritoneal dialysis and transition to hemodialysis. Peritoneal catheters have dacron caps which have the function of counteracting the traction of the catheter itself and at the same time acting as a barrier for microorganisms, preventing the spread towards the peritoneum. Despite this, the same dacron cap can represent a sort of nest for microorganisms to colonize and, with the formation of a biofilm that facilitates their proliferation, make the same organisms impervious to antibiotic therapy and even resistance to them. The most effective tool for monitoring the health status of the exit-site is represented by the objective examination. This examination, through the use of well-defined scales, helps to provide a pathological score of the exit, facilitating the implementation of necessary precautions. In the presence of recurrent exit-site infections, from both Gram positive and Gram negative bacteria, minimally invasive surgical therapy is a valid approach to break this vicious circle. It helps avoid subjecting the patient to the removal of the peritoneal catheter, temporary transition to hemodialysis with the insertion of a central venous catheter, and subsequent repositioning of another peritoneal catheter. We propose the case of a recurrent Staphylococcus Aureus infection resolved after cuff shaving of the exit-site.

Keywords:  peritoneal dialysis, exit-site infection, cuff shaving

Sorry, this entry is only available in Italian.

Introduzione

La via d’accesso al peritoneo continua a costituire un problema nodale nella gestione e nella sopravvivenza della dialisi peritoneale, come lo è l’approccio vascolare in emodialisi. La presenza di un corpo estraneo, il catetere peritoneale, che collega l’ambiente esterno al peritoneo, attraverso cute, sottocute, muscoli e fasce, può favorire le infezioni locali e costituire una via d’accesso per i batteri fino alla cavità peritoneale.

La presenza della cuffia costituisce una barriera protettiva contro l’ingresso dei batteri nel peritoneo, ma a sua volta può essere un fattore irritativo o addirittura un buon nido per i batteri che l’abbiano raggiunta.

La gestione dell’emergenza cutanea del catetere (exit-site) in un paziente in dialisi peritoneale è fondamentale per prevenire ed eventualmente trattare una potenziale infezione della stessa che può rappresentare la porta d’ingresso per i germi e l’evoluzione verso una complicanza più complessa, quale può essere la peritonite che rappresenta poi il rischio fondamentale di fallimento della terapia sostitutiva peritoneale e passaggio all’emodialisi. 

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Palliative and Supportive Dialysis: Current Practices and Recommendations for Best Clinical Practice

Abstract

“Palliative dialysis” is defined as the renal replacement therapy directed to patients living the most critical phases of illness and the end-of-life stage. Offering targeted dialysis prescriptions becomes imperative when health conditions, along with comorbidities, unfavorable prognosis and complications, do not allow standard dialysis to be started or continued. Management should also integrate adequate supportive care measures in both incident and prevalent patients.

This document summarizes nephrological recommendations and scientifical evidence regarding the palliative approach to dialysis, and proposes operative tools for a good clinical practice. After planning and sharing the route of care (“shared-decision-making”), which includes multidimensional evaluation of the patient, a pathway of treatment should be started, focusing on combining the therapeutical available options, adequacy and proportionality of care and patients’ preferences.

We propose a framework of indications that could help the nephrologist in practicing appropriate measures of treatment in patients’ frailest conditions, with the aim of reducing the burden of dialysis, improving quality of life, providing a better control of symptoms, decreasing the hospitalization rates in the end-of-life stage and promoting a home-centered form of care. Such a decisional pathway is nowadays increasingly needed in nephrology practice, but not standardized yet.

Keywords: palliative care, chronic kidney disease, end-of-life, palliative dialysis, hemodialysis, peritoneal dialysis, shared-decision-making

Sorry, this entry is only available in Italian.

Introduzione

L’applicazione dei principi della medicina palliativa nei pazienti affetti da malattia renale ha lo scopo di alleviare le sofferenze legate alla malattia e al suo trattamento, ed è appropriata lungo l’intera traiettoria di malattia, incluso (ma non limitato a) il fine vita [1]. L’attenzione è focalizzata sul trattamento dei sintomi e sul sollievo dell’impatto psicologico, sociale e funzionale della malattia. Poiché le cure palliative trovano indicazione ben oltre gli ultimi giorni di vita, quando sono ancora in atto cure volte a prolungare la sopravvivenza, come la dialisi, le linee guida nefrologiche internazionali ne hanno definito i criteri per la popolazione affetta da malattia renale cronica (Chronic Kidney Disease, CKD), e hanno introdotto il termine di “Kidney Supportive Care” (cure nefrologiche di supporto o cure simultanee), in luogo di “cure palliative” [2, 3].

Se confrontati con i pazienti oncologici, i pazienti affetti da CKD avanzata hanno più probabilità di morire in ospedale, meno probabilità di ricevere istruzioni sul fine vita, e sono gravati da analoga incidenza di sintomi severi, quale il dolore moderato-severo [4].

In Italia nel 2015 viene pubblicato un documento intersocietario (SIN-SICP) da nefrologi e palliativisti, che riassume i criteri prognostici e di identificazione precoce dei bisogni di cure di supporto nella fase finale della CKD, e suggerisce un percorso condiviso con i palliativisti di presa in carico di questi pazienti, percorso che contempla anche la rimodulazione e la sospensione della dialisi, quando in atto [5]. Questo documento ha gettato le basi per l’implementazione delle cure palliative e simultanee nel nostro paese, consentendo di sviluppare le prime esperienze condivise: presso l’Azienda Provinciale per i Servizi Sanitari di Trento dal 2017 è stato attuato un protocollo integrato di cura per la gestione della fine della vita dei nostri nefropatici e dializzati [6]. 

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Role of the Opinions of the Nephrologist and Structural Factors in Dialysis Modality Selection. Results of a Peritoneal Dialysis Study Group Questionnaire

Abstract

Background. The use of PD depends on economic, structural and organizational factors. The nephrologist’s opinion is that peritoneal dialysis is less used than it shold be. In Italy, PD is not carried out in private Centers, but neither is it in around one third of Public Centers. The aim of this study was to investigate the opinions of nephrologists on PD in Public Centers only, thereby nullifying the influence of the economic factors.
Materials and Methods. The investigation was carried out by means of an online questionnaire (Qs) via mail, and during meetings and Congresses in 2006-07. The Qs investigated the characteristics of the Centers, the nephrologists interviewed, and opinions on the various aspects of the choice of Renal Replacement Therapy Renal Replacement Therapy (RRT) (26 questions). Responses were received from 454 nephrologists in 270 public Centers. Among these, 205 centers (370 Qs) report PD (PD-YES), 36 (42 Qs) do not (PD-NO) and 29 (42 Qs) do not use it but send patients selected for PD to other Centers (PD-TRANSF).
Results. The PD-NO and PD-TRANSF Centers are significantly smaller, with greater availability of beds. In the PD-YES Centers the presence of a pre-dialysis pathway, early referral and nurses dedicated solely to PD are associated with a higher use of PD.
The nephrologists in the PD-NO Centers rate PD more negatively in terms of both clinical and non-clinical factors. The belief that more than 40% of patients can do either PD or HD differs among the nephrologists in the PD-YES (74.3%), PD-TRANSF (45.2%) and PD-NO (28.6%) Centers. Likewise, the belief that PD can be used as a first treatment in more than 30% of cases differs among the nephrologists in PD-YES (49.2%), PD-TRANSF (33.3%) and PD-NO (14.3%) Centers.
Conclusions. The use of PD in Public Centers is conditioned by both structural and organizational factors, and by the opinions of nephrologists on the use and effectiveness of the technique.

 

 

Graphical abstract

 

Keywords: Peritoneal Dialysis, Hemodialysis, Modality selection, Physicians opinion, Chronic Kidney Disease

Background

The use of peritoneal dialysis (PD) in the world is limited to a prevalence of approximately <10% [1]. It has long been known [2] how the use of PD in different countries depends on factors which are unrelated to the patient, such as the type of National Health System and the relationship between the public and private sectors in each single country, the reimbursements envisaged for hemodialysis (HD) and PD, the standard of material and social development, and the cost of labor compared with materials [25]. In the absence of financial and structural barriers, the use of PD can be influenced by other factors, such as the type of referral (early or late), the availability of structured educational programs for patients suffering from CKD, PD training during studies and the availability of assisted PD programs, but they presuppose a system which favors the method.

For Italy, a significant contribution to the understanding of the factors influencing the use of PD was made by the Census of the Italian Society of Nephrology (SIN) relating to the state of dialysis in Italy in 2004 [5], which showed that the factors negatively affecting the use of PD were the presence of private centers (which do not use PD), the number of stations available for HD compared to the number of patients on hemodialysis, and the small size of Centers (evaluated by the number of prevalent patients on dialysis). Even considering public Centers alone however, considerable variability was shown in the use of PD, with Centers of limited overall size but relatively extensive PD programs and large Centers without or with small PD programs. This variability suggested that there were other factors capable of influencing the use of PD, such as the so-called “opinion of the doctor”, the importance of which was highlighted by Hingwala [6].

The numerous papers [716] which have investigated the role of doctors in the choice of dialysis modality show a considerable discrepancy between their opinions – generally favorable – and the actual use of PD in their country, which is at times marginal. These papers often show selection bias, in that they are limited to Nephrologists who use PD in some way.

Objectives of the study

In order to investigate “the opinion of doctors on PD and modality selection” and any role this may have in the actual use of PD in a Center, in 2006-2007 what was then SIN’s Peritoneal Dialysis Study Group (GSDP) devised and carried out research – in the form of a questionnaire (Qs) – limited to Public Centers in order to reduce the influence as far as possible of economic factors on the results, but also involving the Centers which did not use PD.

The main aim of the study was to compare opinions relating to PD and modality selection by analyzing the perspective of Nephrologists who work in Centers which use and those which do not use PD.

As the situation relating to PD remains substantially the same 20 years since the first SIN Census, the current PD Project Group decided to attach the results of this survey – which was never published – to the analysis of the 2022 Census data, as besides remaining valid its depth of analysis and the number of Nephrologists involved make it quite unique.

 

Materials and methods

Recruitment of Centers

The study was carried out by means of an on-line questionnaire (Qs) submitted to all non-pediatric Public Dialysis Centers. Aimed at all the Nephrologists in the Center, the filling out of at least 1 per Center was strongly requested. The completion of the Qs took place between January and October 2007, and was incentivized during Congresses and Conferences held during the period. The results were presented partially at Congresses and Conferences at the time, but have never been published.

The list of dialysis Centers eligible for the research was taken from the SIN Census relating to 2004 [5] (2004-SIN-Cens). In short, the 2004-SIN-Cens had documented the presence in Italy of 658 Dialysis Centers. After excluding private and pediatric Centers, the questionnaire was sent to the remaining 346. However, 15 of these 346 Centers had “special statute” status (research Centers) and 6 had no patients on dialysis and were therefore not considered. So as for the 2004-SIN-Cens, the 325 public, non pediatric, ordinary status Centers with a dialysis – PD and HD – incidence of other than zero have been considered in this analysis. As regards the Nephrologists, only “structured” doctors have been considered in this analysis, excluding specialty trainee and attendant doctors.

Breakdown of Centers

The Centers which did not use PD and those which did had been divided in the 2004-SIN-Cens on the basis of a PD incidence of other than or equal to 0 respectively: it was not used in 116 Centers, and was used in 209. The Qs asked again whether or not the Center the interviewee belonged to had a PD program: of the 270 (83.1%) of the respondent Centers, 65 did not use PD. However, 6 of these 65 had been classified in 2004 as Centers using PD, while 13 of the 205 which stated they had a PD program had been classified in 2004 as Centers which did not use it. It is to be remembered that the 2004 classification had been based on PD incidence, a criterion which no longer seemed correct to us today. We therefore reclassified the 2004-SIN-Cens Centers taking account of the prevalence at 31/12/2004 as well, and comparing the data with those of the GSDP Census of 2005 [17], and subsequent years where necessary. Following this reclassification, the number of inconsistencies was reduced to 4 Centers which had terminated their PD programs, and 6 Centers which had started one after 2004.

In the discussion at the time furthermore, a situation had emerged which was more complex than a simple distinction between Centers which used and those which did not use PD. Indeed, some of the Centers not using PD sent patients with indication (clinical or by choice) for PD to other Centers. The Qs took this distinction – not considered in the 2004-SIN-Cens – into account by dividing the Centers into Centers which use PD (PD-YES Centers), Centers which do not use PD but send patients with indication for it to other Centers (PD-TRANSF Centers) and Centers which do not consider it at all (PD-NO Centers).

In conclusion, 270 of the 325 Centers considered took part in the research with at least 1 Qs. Of these, 205 were PD-YES Centers, 36 were PD-NO Centers and 29 were PD-TRANSF Centers. Of the 55 Centers which did not respond to the Qs, 11 had been classified in 2004 as PD-YES Centers and 44 as PD-NO Centers, although their status at the time of the survey is not actually known as they failed to respond to the Qs.

The study did not relate in any way to patients, only to doctors whose participation was voluntary.

The questionnaire and the fields of investigation

The Qs was composed of 26 questions divided into 2 parts. The first defined the characteristics of the Nephrologist interviewed and the Center in which they worked; the second investigated the opinions of the Nephrologist on the validity of PD and the factors which can influence modality selection.

 

Part 1

Characteristics of the Nephrologist

The characteristics of the Nephrologist considered were: 1) training received in PD – 2) actual experience with PD (none, occasional and discontinuous, continuous for less or more than 3 years) – 3) hierarchical role within the Center (head of department/department director, manager, resident doctor) – 4) time effectively dedicated to dialysis (none; <25%; 25-50%; 50-75%; >75% of working hours) and, on a scale of between 1 and 5 (where 1 is only HD, 3 HD and PD equally, 5 only PD), how much time is dedicated to HD and how much to PD – 5) involvement in the choice of dialysis modality (yes/no), and if yes with which tasks (information, clinical evaluation, psychosocial-aptitude evaluation) and the degree of any such involvement, also on a scale of from 1 (little) to 5 (a lot).

Characteristics of the Center

The characteristics of the Center considered were: 1) the existence of a structured dialysis modality selection program (educational and informative, as well as clinical) – 2) the activities performed by the PD nurses (pre-dialysis, day hospital, inpatients, HD) for the PD-YES Centers – 3) the percentage of early referral patients – 4) an opinion on the level of information received by early referral patients in their Center on the different dialysis modalities – 5) the professional roles involved in their Center in the choice of treatment (head of department, HD doctor, PD doctor, HD nurse, PD nurse, nurses with other functions, psychologist). For the last question, the interviewee also had to express an opinion on the weight the professionals involved in the choice of the method had on a scale of from 1 (negligible) to 5 (decisive). For the first three questions (existence of a structured dialysis modality selection program, activities performed by the PD nurses and percentage of early referrals), in the Centers in which more than one Nephrologist responded, the responses did not always match. In the event of disagreement, the value attributed to the Center was determined on a hierarchical scale (in order: response of the Director if available, of the department manager if available, of the doctor with greater involvement in dialysis activities and finally, if there was still no agreement, of the majority). As the percentage of early referrals is numerical, inconsistencies were excessive, so it was not considered in this analysis.

For the last two questions (information provided to patients and weight of the different professional roles in their Center), as the responses involve opinions more than objective values they were considered individually and not adjusted into one sole value per Center.

 

Part 2

This part was divided into three sub-groups of questions. The first investigated the opinion of the doctor on the general factors which can influence the choice of modality, including the validity of the method; the second the opinion on certain conditions – clinical and non-clinical – of the single patients; and the third PD drop-out and duration.

General NON patient-associated factors

The general factors the interviewee had to give a personal evaluation of were: 1) the weight, on a scale of from 1 (none) to 5 (decisive), the doctor, nurse, patient, family members and other patients on RRT have on the choice of treatment for patients without required indications/contraindications for HD or PD. This assessment was requested for both patients with and without barriers to self-care of the PD – 2) the percentage of PD considered optimal on a scale of from <10% to >50% – 3) if they feel conditioned in the choice of mdality by the risk of peritonitis – 4) a comparison of PD with HD in terms of both dialysis efficiency and survival – 5) how much the total cost of the treatment, a shortage of nurses, private centers in the vicinity, the limited size of the Center (number of prevalent patients on dialysis) and HD station occupancy rates can affect the choice on a scale of from 1 (greatly in favor of HD) to 5 (greatly in favor of PD) – 6) the weight that the following incentives can have on favoring the use of PD: financial reimbursement for the caregivers of patients with barriers who are not suitable for self-care of PD (assisted PD), the development of remote care technology (telemedicine), full-time (24H) nursing phone support for patients on PD, home nursing support for patients on PD, financial incentives for residential care homes to assist patients on PD. Opinions were expressed on a scale of from 1 (no weight) to 5 (considerable weight).

Patient-associated factors

This part investigated opinions on certain specific conditions of patients which can represent an indication or contraindication for PD. In detail: 1) the percentage of patients who are eligible for both modalities – 2) the role of clinical and non-clinical factors associated with the patient and listed in Table 1 (the interviewee had to express an opinion on each of the factors listed on a scale of from 1 to 5 according to the following criteria: 1 = high indication for HD; 2 = moderate indication for HD; 3 = indication for either HD or PD; 4 = moderate indication for PD; 5 = high indication for PD).

CLINICAL FACTORS NON-CLINICAL FACTORS
Congestive heart disease Motivation for self-care
Ischemic heart disease Between 65 and 75 years of age
Diabetes Age > 75 years
Obesity (BMI > 30) Not self-sufficient with caregiver available
Malnutrition (BMI < 20) Living alone
Diverticulosis spread beyond the sigma Body image in patients of < 50 years of age
Polycystic nephropathy Working activity
Flexibility in lifestyle and free time
Quality of life
Table 1. Clinical and non-clinical factors influencing the choice which participants were asked to give an opinion on.

Duration of PD / Drop Out

In this last section, the interviewee had to give an opinion on 1) the duration of the PD – 2) the annual percentage of drop out considered “physiological” – 3) if drop out to HD could be influenced by the number of patients being treated.

Analysis

The responses were divided into the 3 types of Center, and compared using the chi-square method or non-parametric tests where indicated. The results were considered significant for p<0.05 up to 0.00001.

 

Results

Participant Centers and nephrologists

Overall the Qs was completed by 454 Nephrologists in 270 Centers (83.1% of the 325 public Centers considered) with a mean participation of 1.68 Nephrologists per Center, which was higher in the PD-YES Centers (Table 2). The percentage of responses in the PD-YES Centers (205 Centers out of 216 = 94.9%) was significantly higher than in the other Centers (65 Centers out of 109 = 59.6%) (p<0.00001). Of the Centers which do not use PD, 29 send patients to other Centers. The number and percentages of Centers which responded and of completed Qs are given in Table 2 and in Figure 1.

CENTERS / Qs PD-YES PD-TRANSF PD-NO TOTAL
Centers (2004-SIN-Cens)* 209 116 325
Qs-Centers ** 216 109 325
Qs-participant Centers *** 205 29 36 270
Nephrologists 370 42 42 454
Qs per Center 1,80 1,45 1,17 1,68
Table 2. At least one nephrologist responded to the Qs in 270 of the 325 Public Centers resulting from the 2004 SIN Census. The participation in the Census was significantly higher in the Centers using PD.
* Centers (2004-SIN-Cens) shows the breakdown of Centers as per the 2004 SIN Census (5). The distinction within the 116 public Centers not using PD of a sub-group of Centers which “rely” on other Centers for PD was not considered at the time. It is to be remembered that this classification was based on the use of PD for incident patients. The breakdown of Centers in the Qs is slightly different for the reasons given under Materials and Methods.
** “Qs Centers” are the Centers reclassified according to the criteria given under Materials and Methods
*** “Qs participant Centers” are the Centers which took part in the survey with at least 1 questionnaire completed
Participation in the survey of Centers with at least 1 Qs completed.
Figure 1. Participation in the survey of Centers with at least 1 Qs completed. In the middle, the division of the 325 non pediatric, ordinary status public Centers. On the right, Qs respondents in the 216 Centers using PD, and on the left in the 109 not using it.

Table 3 (represented in Figure 3) gives the characteristics of the 270 participant Centers taken from the 2004 SIN Census data. HD bed occupancy and Center size (HD + PD patients) were higher (p<0.0001) in the PD-YES Centers than in the others, while there are significant differences between the PD-NO and PD-TRANSF Centers (Qs-YES in Table 3). The comparison with the Centers which did not respond was significantly different (Qs-NO in Table 3 and in Figure 2).

CENTERS PD INCIDENCE (HD+PD) PREVALENCE (HD+PD) HD pt/PL
ALL NO 109 11,9±9,4 50,0±35,3 2,9±0,9
YES 216 28,7±18,4 116,1±65,9 3,4±0,8
Qs YES NO 36 11,4±7,4 48,9±29,9 3,0±1,0
TRASF 29 11,7±9,9 54,4±36,5 2,9±0,7
YES 205 28,9±18,5 116,6±65,8 3,4±0,8
    p<0,0001 p<0,0001 p<0,0001
   
Qs NO NO 44 12,5±10,6 47,8±39 2,9±1,0
YES 11 25,6±16,1 106,9±69,4 3,4±0,8
Table 3. General characteristics (taken from the 2004-SIN-Cens) of the 270 Centers which responded to the Qs (Qs-YES) and the 55 Centers which did not respond (Qs-NO). The comparison was significant between PD-YES Centers and PD-NO and PD-TRANSF Centers, but not between PD-NO and PD-TRANSF Centers or between Qs-YES and Qs-NO.
verall dialysis (HD + PD) incidence and prevalence, and HD prevalent patients per HD bed or station.
Figure 2. Overall dialysis (HD + PD) incidence and prevalence, and HD prevalent patients per HD bed or station. The data are broken down into PD-YES Centers and Centers which do not use PD (NO), in this case whether they do not consider PD or they transfer candidates for PD to other Centers. The same variables have been considered for all the Centers (ALL) and comparing the Centers which took part in the survey (Qs YES) or did not (Qs NO). For those which did take part, the NO Centers have been divided between those which transfer (TRANSF) and those which do not consider PD at all (NO). This distinction was clearly not possible for the Centers which did not respond. As can be seen, among the Centers which took part there was no difference between the PD-NO and PD-TRANSF Centers. The data are as reported in the 2004-SIN-Cens, so they relate to the year 2004.

Dividing the Centers by size and percentage of use of PD (Table 4) at 31/12/2004, though having an extensive dialysis program 17.5% of the Centers do not use PD or use it in less than 10% of patients, while 13.8% of Centers use it in a significant percentage of patients even though they are small in size. As regards the 4 Italian macro areas they belong to, analysis of the 2004-SIN-Cens data had shown how the use of PD was lower in the regions with a higher number of private Centers. The smaller size of the public Centers in these regions was also attributable to the presence of private Centers. Although the relationship between size and use of PD remains, the Centers using PD in the SOUTH are smaller, but with a higher percentage of patients on PD, which is likely to be compensation for the effect of private Centers and the greater number of Centers not using PD. These observations are summarized in Table 5 and Figure 2. The geographical breakdown of the Centers which took part in the Qs is shown in Figure 4.

At the time of the survey, reclassification was not possible due to not having the 2007 prevalence data, so the only variable considered remains the type of Center as defined above.

PD PREVALENCE (%)
0 <10% 10-<20% ≥20%
CENTERS 102 74 76 73
PATIENTS ON DIALYSIS ≤45 81 18.2 3.4 1.8 1.5
46-80 83 7.7 7.4 4.3 6.2
81-130 80 4.3 5.8 6.5 8.0
>130 81 1.2 6.2 10.8 6.8
Table 4. Breakdown of Centers by size (quartiles of the total number of patients on dialysis per Center) and percentage prevalence of PD at 31/12/2004.
NORTH CENTER SOUTH ISLANDS ALL
CENTERS (number) 116 72 93 44 325
HD (prevalent pts) 13,951 5,509 4,911 1,959 26,330
PD (prevalent pts) 2,368 785 761 286 4,200
SIZE (PTS/CENTER) 140.7 87.4 61.0 51.0 93.9
% PD 14.5 12.5 13.4 12.7 13.8
PD-NO/PD-TRANSF CENTERS 17 26 38 21 102
% of ALL Centers 14.7 36.1 40.9 47.7 31.4
HD (prevalent pts) 1,432 1,479 1,214 813 4,938
PD (prevalent pts) 0 0 0 0 0
SIZE (PTS/CENTER) 84.2 56.9 31.9 38.7 48.4
% PD 0 0 0 0 0
PD-YES CENTERS 99 46 55 23 223
% of ALL Centers 85.3 63.9 59.1 52.3 68.6
HD (prevalent pts) 12,519 4,030 3,697 1,146 21,392
PD (prevalent pts) 2,368 785 761 286 4,200
SIZE (PTS/CENTER) 150.4 104.7 81.1 62.3 95.9
% PD 15.9 16.3 17.1 20.0 16.4
Table 5. Characteristics of Centers divided by geographical macro area and distinguishing between the Centers not using PD (PD-NO and PD-TRANSF were not separate in the 2004-SIN-Cens) and those using it (PD-YES). The data are taken from the 2004-SIN-Cens and therefore refer to 2004 and not to the time of the survey (2007).
Breakdown of the 325 Centers in Italy into 4 macro areas as defined by ISTAT
Figure 3. Breakdown of the 325 Centers in Italy into 4 macro areas as defined by ISTAT (NORTH = Valle d’Aosta, Piemonte, Lombardia, Trentino Alto Adige, Friuli Venezia Giulia, Veneto, Emilia Romagna, Liguria – CENTER = Toscana, Marche, Umbria, Lazio – SOUTH = Abruzzo, Molise, Puglia, Campania, Basilicata, Calabria – ISLANDS = Sicily, Sardinia). On the left (A), the average size of the Centers and the percentage PD prevalence (substantially similar). In the middle (B) at the top, the percentage of Centers not using PD (in black) and at the bottom the average size of the Centers that use (grey) and do not use PD (black). As can be seen, the Centers not using PD are always smaller than those using it in the same macro area, but with a gradual reduction from the NORTH to the ISLANDS. So though the principle that the smaller the Center the less PD is used is valid, it can be seen on the right (C) that when only the Centers using PD are considered, those in the SOUTH and ISLANDS use it more even though they are smaller.

Figure 4. Breakdown of the 325 Centers in Italy into 4 macro areas. On the left (A), the 270 Centers which took part, and on the right (B) the 325 eligible Centers. Qs-YES and Qs-NO refer to the Centers which took part in the survey (with at least 1 respondent) and those which did not.

 

PART 1 – CHARACTERISTICS OF THE NEPHROLOGISTS INTERVIEWED AND OF THEIR CENTERS

Characteristics of the Nephrologists

The general characteristics of the Nephrologists taking part are shown in Table 6. There are no significant differences between the 3 types of Center as regards gender (2/3 male) or age (superimposable), while the geographical area where the Center of the interviewee is based (p<0.0001) reflects the distribution of the Centers and the use of PD, which had already been analyzed in the 2004-SIN-Cens (Figures 2 and 3) [5].

CENTERS

(type, number)

NEPHROLOGISTS
(number)
FEMALE
(%)
AV. AGE
(years ± DS)
NORTH
(%)
CENTER

(%)

SOUTH

(%)

ISLANDS

(%)

PD-NO 36 42 38,1 50,8±6,4 14,3 26,2 31,0 28,6
PD-TRANSF 29 42 33,3 51,0±5,4 7,1 7,1 47,6 38,1
PD-YES 205 370 34,1 51,2±6,8 46,5 18,1 19,7 15,7
ALL 270 454 34,4 51,2±6,6 39,9 17,8 23,3 18,9
Table 6. General characteristics of the 454 Nephrologists who responded to the Qs.

Hierarchical role. As regards the hierarchical role of the interviewees, 20.9% hold a top position (Director, Head of Department, Operating Unit manager), 19.6% Department manager (likely to be, but not necessarily, in PD). Specialty trainee and non-resident attending doctors – at the time only present in University Centers – were not considered in this analysis. With regard to the Centers, taking part in 29.3% of cases was the Director/Head or Manager of the Nephrology and Dialysis Operating Unit, in 23.3% of cases the Sub-Department Manager, and in 5.9% both (Table 7). Overall therefore, the Director and/or a Sub-Department Manager took part in 58.5% of the Centers.

Table 7 also shows the age and gender according to different hierarchical roles.

ROLE % PD-NO PD-TRANSF PD-YES AGE Female(%)
HEAD OF DEPT. 95 20.9 38.1 28.6 18.1 53.3±5.7 11.6
SUB-DEPT. MAN. 89 19.6 7.1 14.3 21.6 53.5±4.2 30.3
RESIDENT 270 59.5 54.8 57.1 60.3 48.6±6.3 43.7
ALL 42 42 370 51.2±6.6 34.4
p<0.01 p<0.00001 p<0.00001
Table 7. Hierarchical role of the 454 participants in the survey.

Training and experience. The majority stated that they had received no or insufficient preparation for PD (score “1” or “2”) during their studies.

Interestingly, the percentage of Nephrologists with no or little preparation for PD (sum of the “None”, “1”, “2” percentages given in Table 8) increases significantly from the PD-NO Centers (38.0%) to the PD-TRANSF Centers (47.5%), and reaching 57.6% in the PD-YES Centers (Table 8 and Figure 5-A).

Vice versa, and in this case as expected, their experience with PD (Table 9) is unsurprisingly significantly greater and with continuity in the PD-YES Centers than the others. In particular, more than 3 years experience with PD had been acquired by 16.7% of the Nephrologists in the PD-NO Centers, by 26.2% in the PD-TRANSF Centers and by 65.1% in the PD-YES Centers (Table 9) (Figure 5-B).

Insufficient                                 Suitable for managing
None 1 2 3 4 5
PD-NO 19.0 7.1 11.9 28.6 11.9 21.4
PD-TRANSF 33.3 7.1 7.1 21.4 14.3 16.7
PD-YES 39.5 7.3 10.8 15.1 8.9 18.4
ALL 37.0 7.3 10.6 17.0 9.7 18.5
p<0.04
Table 8. Preparation received on PD while studying.
      Continuous
None Discontinuous <3 years >3 years
PD-NO 40.5 26.2 16.7 16.7
PD-TRANSF 35.7 19.0 19.0 26.2
PD-YES 6.5 20.3 8.1 65.1
ALL 12.3 20.7 9.9 57.0
Table 9. Experience of the 454 participants gained with PD (p<0.0001).
Characteristics of the Nephrologists who took part in the study.
Figure 5. Characteristics of the Nephrologists who took part in the study. A. Training in PD received during the course of their studies (interestingly, the percentage of those who received no training increases from the PD-NO Centers to the PD-YES Centers). B. Experience of more than 3 years with PD of the 454 Nephrologists interviewed by hierarchical role.

Working activity. As regards their area of work, practically all the interviewees (97.0%) handled dialysis. In detail, more than 50% of their working hours were spent on it by 71.4% of those in PD-NO Centers, 76.2% in PD-TRANSF Centers and 64.4% in PD-YES Centers.

While dialysis can be considered as focused only on HD in the Centers which do not use PD, in the PD-YES Centers the percentage of those working mainly or exclusively with PD is 28.6% (106 of 370 Nephrologists), with 18.6% (69 of 370 Nephrologists) dedicating more than 50% of their working time (Table 10).

0 < 25% 26 – 50% 51 – 75% > 75%
NO 0 0 28.6 26.2 45.2
TRANSF 0 11.9 11.9 21.4 54.8
SI 3.0 10.0 22.7 29.5 34.9
only HD 1.4 0.3 1.1 4.6
mainly HD 1.9 3.5 4.6 7.0
HD and PD 4.3 11.4 14.3 14.1
mainly PD 1.1 4.6 6.5 5.4
only PD 1.4 3.0 3.0 3.8
ALL 2.4 9.3 22.2 28.4 37.7
Table 10. Engagement with dialysis – the differences between the three types of Center are not significant. The modality the Nephrologist is involved with clearly only regards the PD-YES Centers.

Engagement in the choice of dialysis modality. Overall, 94.7% (430 interviewees) feel involved in the dialysis modality choice process, with no significant differences between the 3 types of Center (Table 11) either in the extent of their involvement (on a scale of from 1, “little”, to 5, “a lot”: PD-NO 3.7±1.1; PD-NO-TRANSF 4.2 ± 1.2; PD-YES 3.7 ± 1.4; p = NS).

With regard to the 3 aspects of the selection process (information, clinical assessment and aptitude assessment), most of the doctors in the Centers not using PD feel involved in the information (Table 11). Considering only the interviewees involved in the information process, checking the content of the information shows how 42.1% of those in PD-NO Centers say they provide information on both modalities. Although this is lower than the 75.0% in PD-TRANSF Centers and the 84.5% in PD-YES Centers, it was not expected as the percentage relates to Centers which do not use PD and do not send any possible candidates for PD to other Centers (Figure 6). The number of activities performed in the choice process is shown in Table 12.

ASSESSMENT
Not involved Information Clinical Aptitude
PD-NO 2.4 90.5 28.6 28.6
PD-TRANSF 4.8 85.7 59.5 52.4
PD-YES 5.7 73.2 78.9 68.4
ALL 5.3 76.0 72.5 63.2
Table 11. Engagement in the dialysis modality selection process. The differences between the three types of Center are not significant for the percentage of those involved in some way, but neither are they with regard to the degree to which they feel involved in this aspect. Significant, on the other hand, are the differences as regards the method of involvement (information, clinical assessment and social-aptitude assessment). Meanwhile, the different level of engagement in the three activities is to be expected: it is only natural that there is a negligible level of clinical assessment for indications and contraindications for PD in the Centers not using PD, and even more so aptitude assessment.
ACTIVITIES PERFORMED
CENTERS 0 1 2 3
PD-NO 2.4 69.0 7.1 21.4
PD-TRANSF 4.8 40.5 7.1 47.6
PD-YES 5.7 23.0 16.5 54.9
ALL 5.3 28.9 14.8 51.1
p<0.0001
24 131 67 232
DEGREE 0 3.7±1.2 3.8±1.0 4.1±1.1
Table 12. Engagement in the choice of dialysis modality. The numbers show the activities performed in the modality selection process. These activities are information, clinical assessment and social-aptitude assessment. As can be seen, 51.1% (mainly in the PD-YES Centers) say they are involved in all 3 activities with a medium-high level of engagement.
Involvement in dialysis modality selection.
Figure 6. Involvement in dialysis modality selection. A. Percentages of the 430 interviewees involved in the THREE areas of evaluation (information on the methods available, clinical and social-aptitude evaluation) – B. For the 345 Nephrologists involved in information, the modality(ies) illustrated by the interviewee to the patient. As can be seen, more than 40% of the Nephrologists in the PD-NO Centers say they also provide information on PD.

Characteristics of their Centers

The responses to this part of the survey can in some cases be considered opinions, as will be specified in the individual aspects. For some questions, in some Centers in which more than one Nephrologist took part conflicting assessments emerge between the Nephrologists in the same Center. These cases were resolved as reported under Materials and Methods.

Dialysis modality selection pathway. The existence of a pre-dialysis pathway increases from 47.2% in PD-NO Centers and 55.2% in PD-TRANSF Centers to 73.2% in the 205 PD-YES Centers (p<0.00005) (Figure 7). Of the 97 Centers with more than one Qs, the response of all the participants in 61 Centers (62.9% – 3.1 Qs per Center) is in agreement, while in the remaining 36 Centers (37.1% – 2.6 Qs per Center) there is at least one response which is not in agreement with the other Nephrologists in the same Center. In 6 of these 36 Centers, the response of the head of department or department manager is not in agreement with that of the majority; in particular, in 1 case for the Head of Department/Director there is no pathway while the majority confirm there is, with the opposite in 5 cases.

 Presence of a structured pathway
Figure 7. Presence of a structured pathway (with dedicated personnel and a pre-defined assessment program) in the different types of Center.

Other activities performed by the PD nurse. Of the 205 Centers performing PD, the nurse is dedicated exclusively to PD in just 26 (12.7%), while for the activities considered (pre-dialysis, day hospital activities, inpatients and HD) the PD nurse is responsible for 1, 2, 3 and all 4 in 45.4% (93 centers), 28.8% (59 centers), 10.7% (22 centers) and 2.4% (5 centers) respectively of the remaining 244 Centers (Figure 8). The main activity the PD nurse is engaged in is Pre-dialysis (Figure 8). The size of the PD program is inversely proportional to the number of “other activities” (Figure 9).

Other activities carried out by the nurses who are involved with PD.
Figure 8. Other activities carried out by the nurses who are involved with PD. The data obviously refer to the 205 PD-YES Centers. A. Number of other activities performed (the nurses are exclusively dedicated to PD in only 13% of the Centers). B. Type of activity carried out as a proportion of “other activities”.
The number of “other activities” performed by PD nurses increases as the patients treated with PD reduces
Figure 9. The number of “other activities” performed by PD nurses increases as the patients treated with PD reduces. Obviously the chart can also be read in reverse: the higher the number of other activities performed, the lower the number of patients on PD.

Completeness of the information provided to patients (opinion). Incident HD patients are adequately informed on HD, but not on PD in all three types of Center, though as regards the latter the level improves from the PD-NO Centers to the PD-YES Centers (Table 13). For incident PD patients, the level of information on the two methods is equivalent (not considering, obviously, the PD-NO Centers). The result does not change when the responses given by doctors involved in dialysis activities for more than 50% of their working time are considered.

HD INCIDENT PD INCIDENT
INFORMATION PROVIDED HD PD HD PD
NO 4.4 2.8
NO-TRANS 4.4 3.3 3.0 3.2
YES 4.2 3.7 4.3 4.7
ALL 4.2 3.6 4.0 4.3
N.S. p<0.00005 p<0.00001 p<0.00001
Table 13. Information provided to early referral incident patients.

Influence of different healthcare practitioners in the choice of modality (opinion). The healthcare practitioners considered as having a decisive role in their Center in the choice remain the head of department and the HD doctor for all Centers, while the PD doctor and nurse only have influence in the PD-YES Centers (Figure 10). For the psychologist, the response (some weight only in the PD-YES Centers) depends clearly on the availability of this service, confirming the presence in the PD-YES Centers of a more well-structured pre-dialysis pathway. The Head of Department is recognized as having a decisive role, even though the weight attributed depends on the role of the interviewee (Figure 11).

Opinion on the weight (from left to right) of the Head of
Figure 10. Opinion on the weight (from left to right) of the Head of Department (Director or Operating Unit Manager), the HD Doctor, the PD Doctor, a Doctor not involved with Dialysis, the HD nurse, the PD nurse, a Nurse not directly involved with Dialysis and lastly the Psychologist. The differences relating to PD Doctor and Nurse are as expected, as is the superimposable opinion between PD-NO and PD-TRANSF Centers. The interviewees in all the three types of Center agree on the role of the Head of Department.
Opinion on the role of the Head of Department in the choice depending on the role of the interviewee
Figure 11. Opinion on the role of the Head of Department in the choice depending on the role of the interviewee (Head of Department, Sub-department Manager or resident doctor). The weight is expressed as the mean (± DS) of the weight score attributed by the three professionals to the Head of Department (scores from 0 – no weight – to 5, decisive).

 

PART 2 – THE OPINIONS OF THE NEPHROLOGISTS

General non patient-dependent factors

Weight of different parties, including patient and family members (opinion) in self-sufficient and NON self-sufficient patients. Overall (considering all 3 types of Center together), the “weight” attributed to the doctor and nurse is the same whether the patient is self-sufficient or not. As expected, the “weight” attributed to the patient is greater when the patient is self-sufficient, while for those who are not self-sufficient the family member’s opinion is even more important than that of the doctor (Figure 12). The role of other patients is less important, and minimal for non self-sufficient patients.

Differences in the type of Center they belong to are highlighted in the opinion expressed on the importance of the nurse, patient and family members in the choice of modality (Figure 13) (Figure 14). For self-sufficient patients all three of these are assigned a significantly greater role by the interviewees in the PD-YES Centers than in the other Centers. For NON self-sufficient patients, the difference between PD-YES Centers and the others only relates to the nurse and family member (Figure 14).

Overall opinion (all Centers) on the role that the main professionals
Figure 12. Overall opinion (all Centers) on the role that the main professionals involved have in dialysis modality selection in patients who are self-sufficient or need a caregiver for PD. The value is the mean score (in this case the scale is from 1 – absent or irrelevant – to 5, decisive).
Opinion by type of Center on the weight the main professionals involved have in dialysis modality selection
Figure 13. Opinion by type of Center on the weight the main professionals involved have in dialysis modality selection in self-sufficient patients. The value is the mean score (in this case the scale is from 1 – absent or irrelevant – to 5, decisive).
Figure 14. Opinion by type of Center on the weight the main professionals involved have in dialysis modality
Figure 14. Opinion by type of Center on the weight the main professionals involved have in dialysis modality selection in NON self-sufficient patients (need for a caregiver for PD). The value is the mean score (in this case the scale is from 1 – absent or irrelevant – to 5, decisive).

Optimal percentage of PD. The responses relating to the percentage considered optimal confirm the importance of the type of Center in which the Nephrologist works (Table 14). Those working in Centers which do not use PD express significantly lower percentages as optimal for the use of PD compared to the others. The percentage does not change when only the 350 Nephrologists spending more than 50% of their time on dialysis and heads of department are considered (Figure 15).

OPTIMAL % NO TRANSF SI
=< 10 21.4 2.4 0.3
between 11 and 20 28.6 31.0 19.5
21 – 30 35.7 33.3 31.1
31 – 40 7.1 11.9 28.6
41 – 50 7.1 21.4 13.8
> 50 0.0 0.0 6.8
Table 14. Evaluation of the percentage of patients on dialysis with PD considered optimal (p<0.00001).
Optimal percentage use of PD according to Nephrologists in the different types of Center.
Figure 15. Optimal percentage use of PD according to Nephrologists in the different types of Center. In B, only the 350 Nephrologists with high involvement in dialysis (more than 50% of work time dedicated to dialysis) are considered. There are no significant differences between A and B.

 Fear of peritonitis. Of the 454 interviewees, 24 were not considered because they are not involved in any way in the modality selection process. Being conditioned by a fear of peritonitis is referred to by 48.8%, 19.5% and 15.5% respectively of the Nephrologists in PD-NO, PD-TRANSF and PD-YES Centers (Table 15). Considering only those with more than 3 years of experience with PD, the difference is not more significant, but the limited number of interviewees with >3 years experience in the PD-NO and PD-TRANSF Centers (a total of 16 out of 82), intriguing though it may be, does not allow for the drawing of certain conclusions in this regard, while in the PD-YES Centers there is no significant difference between those who have more or less than 3 years of experience in PD (Figure 16).

FEAR OF PERITONITIS NO TRANSF SI
NO 21 32 295
YES 20 8 54
Table 15. The fear of peritonitis diminishes from the PD-NO Centers (48.8%) to the PD-TRANSF (20.0%) and PD-YES Centers (15.5%).
 Influence of the fear of peritonitis in the choice process,
Figure 16. Influence of the fear of peritonitis in the choice process, considering only the 430 Nephrologists involved in the choice. A. All participants – B. Breakdown by having less or more than 3 years experience.

Validity of the method: adequacy. Table 16 gives the percentages of the different opinions expressed by the interviewees on the validity of clearance adequacy in PD compared to HD. The majority of PD-NO Centers consider it to be lower, while in the PD-TRANSF and PD-YES Centers the majority considered it to be the same or superior (Figure 17). The result does not change if only the interviewees with a high level of involvement in the modality selection pathway are considered.

DIALYSIS ADEQUACY SURVIVAL
CENTERS LOWER EQUAL HIGHER LOWER EQUAL HIGHER
NO 57.1 40.5 2.4 45.2 47.6 7.1
TRANSF 35.7 45.2 19.0 21.4 54.8 23.8
YES 25.7 61.4 13.0 14.1 64.9 21.1
ALL 29.5 57.9 12.6 17.6 62.3 20.0
Table 16. Evaluation of the validity of PD compared to HD. Both are evaluated in a significantly different way in the three types of Center (dialysis adequacy p<0.0005 – survival p<0.00002).
Figure 17. Evaluation of dialysis adequacy in PD compared to HD.
Figure 17. Evaluation of dialysis adequacy in PD compared to HD.

Validity of the method: survival. The results for survival are similar to those for adequacy, though less marked (Table 16) (Figure 17). The majority of participants believe it to be the same in all three types of Center, but only a few fewer in the PD-NO Centers believe it to be worse (47.6% the same – 45.2% worse). The opposite is true in the PD-YES Centers (64.9% the same – 14.1% worse) and in between in the NO-TRANSF Centers (54.8% the same – 28.1% worse). The result does not change when only the 300 interviewees with high involvement in dialysis are considered (lower survival rate – NO = 43.3% – TRANSF = 21.9% – YES = 13.0% – same survival rate – NO = 53.3% – TRANSF = 50.0% – YES = 64.3%)

Structural factors conditioning the use of PD. Of the 5 factors considered (cost, shortage of nurses, closeness to private Centers, limited overall size of Center, excess HD beds) the majority in all three types of Center agree that private Centers in the vicinity, limited size of Center and excess HD beds are factors favoring HD (Table 17) (Figures 18, 19). The majority belonging to PD-NO Centers do not consider cost to be an important factor, while in the PD-TRANSF and PD-YES Centers they consider it an indication for PD. This difference in opinion on costs is no longer significant when only the highly-involved Nephrologists are considered. The opinion expressed on the shortage of nurses as a conditioning factor is similar: the majority (38.1%) in the PD-NO Centers consider it a deciding factor, while in the TRANSF and YES Centers (61.9% and 66.8% respectively) it is considered an indication for PD, both overall and by just Nephrologists with high involvement in dialysis. In the PD-NO Centers however, more than a quarter of the interviewees (26.1%) consider it an indication for HD.

INDICATION FOR HD (1 – 2); INDIFFERENT (3); INDICATION FOR PD (4 – 5)
  1 2 3 4 5
COST (p<0.05)
NO 4.8 4.8 59.5 23.8 7.1
TRANSF 7.1 4.8 28.6 33.3 26.2
YES 3.0 3.8 36.2 26.8 30.3
ALL 3.5 4.0 37.7 27.1 27.8
SHORTAGE OF NURSES (p<0.0001)
NO 11.9 14.3 38.1 26.2 9.5
TRANSF 14.3 7.1 16.7 42.9 19.0
YES 3.0 5.7 24.6 33.8 33.0
ALL 4.8 6.6 25.1 33.9 29.5
PRIVATE CENTERS IN THE VICINITY (N.S.)
NO 47.6 14.3 38.1 0.0 0.0
TRANSF 28.6 19.0 42.9 7.1 2.4
YES 33.5 12.2 43.5 5.4 5.4
ALL 34.4 13.0 43.0 5.1 4.6
LIMITED SIZE OF CENTER (N.S.)
NO 28.6 23.8 31.0 14.3 2.4
TRANSF 33.3 9.5 35.7 14.3 7.1
YES 18.1 22.4 35.7 14.1 9.7
ALL 20.5 21.4 35.2 14.1 8.8
EXCESS HD BEDS (N.S.)
NO 54.8 16.7 23.8 2.4 2.4
TRANSF 38.1 19.0 28.6 7.1 7.1
YES 36.2 17.6 33.5 6.2 6.5
ALL 38.1 17.6 32.2 5.9 6.2
Table 17. Evaluation, as indication for PD or HD, of the structural factors given in the Table. If only the interviewees (300) with high involvement in the choice process (data not shown) are considered, the difference regarding the opinion between the three types of Center on cost is no longer significant.
Overall evaluation (454 Nephrologists) of indication for PD or HD
Figure 18. Overall evaluation (454 Nephrologists) of indication for PD or HD for each of the structural factors reported above on a scale of from 1 to 5.
Evaluation of indication for PD or HD
Figure 19. Evaluation of indication for PD or HD for each of the structural factors reported above on a scale of from 1 to 5. Participants have been divided by the type of Center they belong to.

Possible incentives for PD. The majority of interviewees (Figure 20) (Table 18) judge all 5 incentives considered positively. Analysis by type of Center shows significant differences regarding financial support for assisted PD, telemedicine and the application of financial incentives for residential care homes willing to manage PD: financial support for assisted PD and residential care homes is warmly supported by those belonging to PD-TRANSF and PD-YES Centers, and telemedicine by the PD-NO Centers (Figure 21).

from no importance (1) to considerable weight (5)
  1 2 3 4 5
FINANCIAL SUPPORT FOR ASSISTED PD (p<0.00001)
NO 33.3 16.7 16.7 21.4 11.9
TRANSF 14.3 4.8 28.6 26.2 26.2
YES 4.9 6.8 15.4 28.4 44.6
ALL 8.4 7.5 16.7 27.5 39.9
TELEMEDICINE (p<0.0005)
NO 7.1 7.1 14.3 54.8 16.7
TRANSF 2.4 7.1 31.0 31.0 28.6
YES 11.1 17.0 26.2 25.9 19.7
ALL 9.9 15.2 25.6 29.1 20.3
24H NURSE PHONE SUPPORT (N.S.)
NO 2.4 4.8 14.3 57.1 21.4
TRANSF 0.0 7.1 16.7 38.1 38.1
YES 3.2 9.2 17.0 34.1 36.5
ALL 2.9 8.6 16.7 36.6 35.2
HOME NURSING SUPPORT (N.S.)
NO 4.8 4.8 16.7 40.5 33.3
TRANSF 0.0 2.4 14.3 38.1 45.2
YES 2.4 3.8 9.7 29.5 54.6
ALL 2.4 3.7 10.8 31.3 51.8
FINANCIAL SUPPORT FOR RESIDENTIAL CARE HOMES (p<0.0005)
NO 7.1 4.8 28.6 42.9 16.7
TRANSF 2.4 7.1 19.0 33.3 38.1
YES 3.5 4.9 10.8 26.5 54.3
ALL 3.7 5.1 13.2 28.6 49.3
Table 18. Evaluation of the weight that the incentives for PD given in the Table have on the choice for PD according to Nephrologists by type of Center.
Figure 20. Opinion of the effectiveness
Figure 20. Opinion of the effectiveness of various initiatives generally considered to be incentives for PD: financial support for Caregivers in assisted PD; telemedicine; 24H nurse phone support; home nurse support; financial support for residential care facilities willing to accept and manage patients on PD. All interviewees (454 Nephrologists).
Opinion of Nephrologists of the effectiveness of various initiatives generally considered to be incentives for PD
Figure 21. Opinion of Nephrologists of the effectiveness of various initiatives generally considered to be incentives for PD divided by the type of Center they belong to.

General patient-dependent factors

Together these represent the most common clinical and social-aptitude indications and contraindications to PD which are normally evaluated during the pre-dialysis process.

Percentage of patients with no conditioning. The percentage of early referral patients who are free to choose between HD and PD is evaluated in a significantly different way depending on the type of Center a nephrologist belongs to (Table 19). In particular, while it is believed to be less than 50% of incident patients for 92.8% of interviewees in the PD-NO Centers, 47.6% in the PD-YES Centers believe it to be more than 50% (Figure 22), with the result not changing taking into account only the 300 interviewees with high involvement in dialysis (96.7% and 48.3% respectively).

≤40% 40-50% 50-60% 60-70% ≥70%
NO 71.4 21.4 4.8 0.0 2.4
NO-TRANSF 54.8 23.8 9.5 4.8 7.1
YES 25.7 26.8 21.1 14.1 12.4
ALL 32.6 26.0 18.5 11.9 11.0
Table 19. Percentage of patients free to choose dialysis modality (p<0.00001).
Opinion of the percentage of total incident patients in dialysis with no clinical or social conditioning
Figure 22. Opinion of the percentage of total incident patients in dialysis with no clinical or social conditioning and therefore able to choose either PD or HD.

Particular clinical conditions. Figure 23 compares the assessments given by those belonging to NO and TRANSF Centers considered together (82 interviewees) with those belonging to YES Centers (370 interviewees), considering together high or moderate indication for HD (responses 1 and 2) and PD (responses 4 and 5). On ischemic heart disease, malnutrition and diverticulosis, the responses – indication for PD for CAD and contraindication for PD for BMI<20 and diverticulosis spread beyond the sigma – do not differ significantly between the different types of Center. Opposite evaluations, on the other hand, were given by the majority of the interviewees for heart failure (indication for the PD-YES Centers and contraindication or indifferent for the PD-NO/TRANSF Centers) and polycystic nephropathy (contraindication for the PD-NO/TRANSF Centers and indifferent for the PD-YES Centers) (Figure 24). With regard to Type 2 DM, the proportion among those in the PD-NO/TRANSF Centers who expressed indifference or consider it an indication for PD (indifferent 41.7% – indication 35.7%) is higher than among those belonging to the PD-YES Centers (indifferent 52.4% – indication 21.9%). For obesity too, which is considered by over 75% in both groups to be a contraindication for PD, indifference is higher in the NO/TRANSF Centers (17.9% vs 8.4%). The difference between NO and TRANSF Centers was only significant with regard to Polycystic nephropathy (Figure 24); for all the other conditions the differences in evaluation between NO and TRANSF Centers were not significant.

The results for all three types of Center with the responses on a scale of from 1 to 5 are given in detail in Table 20.

INDICATION FOR HD (1 – 2); INDIFFERENT (3); INDICATION FOR PD (4 – 5)
1 2 3 4 5
CONGESTIVE HEART FAILURE (p<0.005)
NO 28.6 14.3 16.7 33.3 7.1
TRANSF 23.8 14.3 19.0 31.0 11.9
YES 11.1 10.8 17.6 29.2 31.4
ALL 13.9 11.5 17.6 29.7 27.3
ISCHEMIC HEART DISEASE (p<0.0005)
NO 14.3 7.1 26.2 45.2 7.1
TRANSF 2.4 4.8 21.4 52.4 19.0
YES 1.6 5.4 30.0 38.9 24.1
ALL 2.9 5.5 28.9 40.7 22.0
DIABETES (p<0.01)
NO 14.3 11.9 47.6 23.8 2.4
TRANSF 7.1 11.9 35.7 31.0 14.3
YES 5.1 20.5 52.4 15.9 5.9
ALL 6.2 18.9 50.4 18.1 6.4
OBESITY – BMI>30 kg/m² (N.S.)
NO 57.1 16.7 21.4 4.8 0.0
TRANSF 50.0 33.3 14.3 0.0 2.4
YES 52.4 35.1 8.4 3.2 0.8
ALL 52.6 33.3 10.1 3.1 0.9
MALNUTRITION – BMI<20 kg/m² (p<0.05)
NO 38.1 14.3 9.5 35.7 2.4
TRANSF 31.0 23.8 19.0 14.3 11.9
YES 24.1 23.2 25.7 19.7 7.3
ALL 26.0 22.5 23.6 20.7 7.3
DIVERTICULOSIS SPREAD BEYOND THE SIGMA (p<0.01)
NO 57.1 16.7 21.4 0.0 4.8
TRANSF 66.7 19.0 7.1 2.4 4.8
YES 41.9 35.9 17.3 3.5 1.4
ALL 45.6 32.6 16.7 3.1 2.0
APKD (p<0.00001)
NO 35.7 23.8 35.7 0.0 4.8
TRANSF 50.0 33.3 11.9 0.0 4.8
YES 15.4 25.7 50.3 5.9 2.7
ALL 20.5 26.2 45.4 4.8 3.1
Table 20. Detailed evaluation of the single clinical factors (in percentages) on which the opinion of the Nephrologists was requested.
Evaluation of the main clinical factors which can condition the choice of modality.
Figure 23. Evaluation of the main clinical factors which can condition the choice of modality. 1. «CHF» Congestive heart failure; 2. «CAD» Ischemic heart disease; 3. «DM» type 2 Diabetes Mellitus; 4. «BMI>30» Obesity; 5. «BMI<20» Malnutrition; 6. «Diverticulosis», understood as diverticulosis spread beyond the sigma; 7. «ADPKD» Polycystic nephropathy. NOTE – The interviewees in the NO and TRANSF Centers (82) were considered together and compared with those of the PD-YES Centers (370).
Polycystic nephropathy and congestive heart failure in the opinion of the interviewees divided by type of Center.
Figure 24. Polycystic nephropathy and congestive heart failure in the opinion of the interviewees divided by type of Center.

Particular social conditions (NON-clinical factors associated with the patient). Figure 25 and Figure 26 compare the assessments given by those belonging to NO and TRANSF Centers considered together (82 interviewees) with those belonging to YES Centers (370 interviewees), considering together high or moderate indication for HD (responses 1 and 2) and PD (responses 4 and 5). The interviewees agree (p= N.S.) that motivation for self-care, working activity, a need for flexibility in times for dialysis and – in the case of NON self-sufficient patients – the availability of a caregiver all represent indications for PD, just as not sticking with the therapy (NON compliance) is a valid indication for HD. Opinions are significantly different between the three groups, on the other hand, with regard to the importance of body image, age, quality of life and living alone. Body image in particular is considered an indication for HD by 52.4% in PD-NO/TRANSF Centers, while 62.7% in the PD-YES Centers consider it to be an indication for PD or are indifferent (p<0.05); while Quality of Life is considered an indication for PD by 51.2% in the PD-NO/TRANSF Centers, with the percentage rising to 67.3% in the PD-YES Centers (p<0.01); an age of between 65 and 75 is considered an indication for HD or indifferent by 15.5% and 50.0% respectively in the PD-NO/TRANSF Centers, while in the PD-YES Centers these percentages are 4.1% and 57.3% respectively (p<0.0005); the difference is more marked for > 75 years of age, considered an indication for HD by 48.8% of the interviewees in PD-NO/TRANSF Centers compared with 24.3% in the PD-YES Centers (p<0.00005); finally, living alone is an indication for HD for 78.6% in PD-NO/TRANSF Centers compared with 51.6% in PD-YES Centers (p<0.00005).

NON clinical conditions evaluated according to level of indication for HD or PD.
Figure 25. NON clinical conditions evaluated according to level of indication for HD or PD. «MOTIVAT. SELF-CARE»: patient motivated for self-care dialysis; «FLEXIBILITY» in treatment times; «Q of L»: Quality of Life; «NON COMPLIANCE»: limited compliance with prescriptions. NOTE – The interviewees in the NO and TRANSF Centers (84) were considered together and compared with those of the PD-YES Centers (370).
 NON clinical conditions evaluated according to level of indication for HD or PD.
Figure 26. NON clinical conditions evaluated according to level of indication for HD or PD. «ASSIST-PD»: NON self-sufficient patient needing a CareGiver (CG) who is available. NOTE – The interviewees in the NO and TRANSF Centers (82) were considered together and compared with those of the PD-YES Centers (370).

For all the NON clinical conditions considered, the differences in evaluation between PD-NO and PD-TRANSF Centers was not significantly different. The results for all three types of Center are given in detail in Table 21, with the responses on a scale of from 1 to 5. The results of the analysis limited to the 300 Nephrologists with high involvement in dialysis activities proved to be superimposable with those given in Table 21.

INDICATION FOR HD (1 – 2); INDIFFERENT (3); INDICATION FOR PD (4 – 5)
1 2 3 4 5
MOTIVATION FOR SELF-CARE (p<0.00001)
NO 2.4 0.0 0.0 64.3 33.3
TRANSF 0.0 0.0 4.8 31.0 64.3
YES 0.8 0.5 2.4 13.0 83.2
ALL 0.9 0.4 2.4 19.4 76.9
AGED BETWEEN 65 AND 75 (p<0.0005)
NO 7.1 9.5 57.1 21.4 4.8
TRANSF 4.8 9.5 42.9 35.7 7.1
YES 0.3 3.8 57.3 25.9 12.7
ALL 1.3 4.8 55.9 26.4 11.5
AGE > 75 (p<0.00001)
NO 40.5 11.9 19.0 21.4 7.1
TRANSF 21.4 23.8 23.8 14.3 16.7
YES 5.1 19.2 40.0 24.6 11.1
ALL 9.9 18.9 36.6 23.3 11.2
NOT SELF-SUFFICIENT WITH CAREGIVER AVAILABLE (p<0.005)
NO 11.9 7.1 11.9 61.9 7.1
TRANSF 19.0 4.8 19.0 40.5 16.7
YES 8.6 6.2 10.3 40.5 34.3
ALL 9.9 6.2 11.2 42.5 30.2
LIVING ALONE (p<0.005)
NO 50.0 26.2 21.4 0.0 2.4
TRANSF 42.9 38.1 11.9 4.8 2.4
YES 25.1 26.5 40.3 5.4 2.7
ALL 29.1 27.5 35.9 4.8 2.6
BODY IMAGE (p<0.05)
NO 26.2 31.0 35.7 7.1 0.0
TRANSF 23.8 23.8 40.5 9.5 2.4
YES 8.6 28.6 50.3 9.2 3.2
ALL 11.7 28.4 48.0 9.0 2.9
WORK (p<0.05)
NO 2.4 4.8 19.0 59.5 14.3
TRANSF 2.4 4.8 19.0 38.1 35.7
YES 1.6 1.9 17.3 33.5 45.7
ALL 1.8 2.4 17.6 36.3 41.9
TIME FLEXIBILITY (p<0.005)
NO 7.1 0.0 14.3 61.9 16.7
TRANSF 0.0 2.4 14.3 47.6 35.7
YES 1.4 0.5 10.8 34.3 53.0
ALL 1.8 0.7 11.5 38.1 48.0
QUALITY OF LIFE (p<0.00001)
NO 2.4 2.4 47.6 45.2 2.4
TRANSF 0.0 11.9 33.3 40.5 14.3
YES 1.4 1.9 29.5 28.6 38.6
ALL 1.3 2.9 31.5 31.3 33.0
NON COMPLIANCE (p= N.S.)
NO 71.4 11.9 14.3 2.4 0.0
TRANSF 66.7 14.3 11.9 4.8 2.4
YES 67.6 17.0 12.2 1.6 1.6
ALL 67.8 16.3 12.3 2.0 1.5
Table 21. Detailed evaluation of the single NON clinical factors (in percentages) on which the opinion of the Nephrologists was requested.

Duration of PD and drop-out to HD

Duration of PD. When asked if drop-out from PD was to be considered a probable event after 2, 4 or 5 years, or whether PD has no definable time limit a priori, the responses were significantly different, as reported in Table 22. Rather than being a division between those who believe it has a predetermined duration and those who do not (p=N.S.) however, the difference relates to the estimate of the duration given by the former (Figure 27). Limited to the 300 interviewees with high involvement in dialysis, the result of the same analysis was not significant.

2 years 3 years 5 years UNDEFINED
NO 14.3 19.0 19.0 47.6
TRANSF 2.4 21.4 19.0 57.1
YES 2.7 11.6 30.5 55.1
ALL 3.7 13.2 28.4 54.6
 Table 22. Duration of PD.
The duration of PD in the opinion of the interviewees divided by type of Center.
Figure 27. The duration of PD in the opinion of the interviewees divided by type of Center.

Duration of PD and size of PD program. The majority of the interviewees (63.7%) believe that the size of a Center’s PD program (total number of patients treated and/or in treatment) has no influence on the percentage of drop-out to HD (Figure 28-A), with no significant differences among the three types of Center (or when considering only the 300 with high involvement in dialysis).

Figure 28. The response on annual drop-out rate is similar to that on the duration of PD (A). In B, the opinion of the Nephrologists, divided by type of Center, on the influence the size of PD program can have on drop-out.
Figure 28. The response on annual drop-out rate is similar to that on the duration of PD (A). In B, the opinion of the Nephrologists, divided by type of Center, on the influence the size of PD program can have on drop-out.

Percentage of annual drop-out. The interviewees in the three types of Center also gave a similar response to this question (Figure 28-B). Overall, 48.9% believe there is no PHYSIOLOGICAL drop-out percentage, while among the remainder 17.6% and 19.6% respectively consider it to be lower than 6% or between 6 and 10%.

Interest for the subject. When asked “In future, would you like to be informed of the results of this questionnaire and any new initiatives which may follow?”, a total of 91.6% expressed interest, though there was a strongly significant difference between the types of Center. Indeed, while almost all those belonging to YES Centers (98.6%) expressed interest, in the NO Centers the percentage of those interested drops to 47.6% (Figure 29).

Figure 29. The response to this question, asked more out of courtesy than as part of the survey, can be an indicator of interviewee interest in PD.
Figure 29. The response to this question, asked more out of courtesy than as part of the survey, can be an indicator of interviewee interest in PD.

 

Discussion

The 2004-SIN-Cens had shown the importance of structural factors (number of private Centers, size of Center and HD station occupancy rate) in the use of PD: Centers not using PD are smaller, have a lower HD bed occupancy rate and are located in regions where there are numerous private Dialysis Centers. If structural factors alone counted, opinions on PD would be no different between those using PD and those not using it; however, they were shown to be significantly different depending on the type of Center respondents belonged to: negative when it does not use PD and positive in those that do.

As choosing a place to work generally precedes work experience, opinions on PD seem to be defined according to experience gained with the method, confirming the importance of structural factors on use of the modality. However, the importance alongside structural factors of positive opinions of the modality is shown by the fact that there are Centers (PD-TRANSF) which have the same structural characteristics as Centers which do not consider PD at all due to size (small) and HD bed occupancy (low), yet send candidates for PD to other Centers.

In short, the use of PD in public Centers in Italy seems to be the result of balancing structural factors and opinions, with the latter however being conditioned – though only partially – by the former as opinions are enhanced with the gaining of experience in PD.

The main results of the study are summarized in Table 23.

Characteristics of the Nephrologists and their Centers

As regards the Nephrologists in the three types of Center, the only significant difference relates – naturally – to experience with PD, while their personal characteristics, training and engagement with dialysis, and degree of involvement in the choice of modality are substantially similar. The Centers which took part in the survey are not significantly different to those which did not. The main difference between the 3 types of Center regards the presence to a lesser extent of a structured modality selection pathway in the PD-NO Centers than in the PD-YES Centers, and in between the two in the PD-TRANSF Centers. Matching this is the percentage of those involved in all the 3 components of the choice (information, clinical evaluation and social-aptitude evaluation). If this concurs with the nature of the Center (choice is not an issue where PD is not performed), the level of participation of those who define themselves as being involved in the choice is medium-high in all three types of Center. This contradiction could represent a different cultural approach essentially limiting the choice in the PD-NO Centers to information. Strangely however, even in the PD-NO Centers HD incident patients are informed on PD, although insufficiently. Despite this, the difference between PD-NO and PD-YES Centers in regard to the information provided to patients is of note (2.8 vs 3.7 respectively on a scale of from 1 to 5). As the question on information provided related to early referral patients, but did not specify an absence of contraindications for PD, this information may be influenced by these contraindications, which are logically more numerous in HD incident patients in PD-YES Centers (in everyday practice, the existence of contraindications for PD is considered grounds for making informing the patient on this method “unnecessary”).

Opinions: roles played in making the choice

In accordance with the above, there is a clear difference in the way the percentage of patients who could do either PD or HD (with no contraindications) is assessed by Nephrologists in the three types of Center. If the choice is influenced by the healthcare practitioners, everyone recognizes as regards their own Center the decisive role played by the Director, while the weight attributed to other professionals, such as the PD doctor or nurse and psychologist, depends obviously on the type of Center and availability of the Service. Of interest is the role of the psychologist, which is important only in the PD-YES Centers, indicating a more well-structured selection pathway in these Centers. As regards the roles in general of the doctor, nurse, patient, family members and other patients, everyone agrees that the doctor is key, the patient or family members (depending on whether the patient is self-sufficient or not) are important, and other patients are irrelevant. The main difference between the three types of Center lies in the assessment of the role of the nurse, which is seen as NON marginal only by 14.3% of the Nephrologists in the PD-NO Centers compared to 60.5% in the PD-YES Centers.

Opinions: validity of the method, optimal percentage and drop-out

Opinions on adequacy and survival in PD compared to HD also differ considerably in the three types of Center: worse for the PD-NO Centers, the same or better than HD in the PD-YES Centers. Around half believe that PD has no predefined duration, with no differences between the Centers; however, the percentage of the other half who give it a maximum duration of 2 or 3 years compared to 5 years is significantly higher in the PD-NO Centers. It is therefore only natural that just 14.3% in the PD-NO Centers consider a proportion of patients treated with PD of more than 30% optimal, while the proportion is below 10% in 21.4% in these Centers, unlike the others. This means, however, that for 64.3% in the PD-NO Centers the optimal proportion of patients treated with PD is between 10 and 30% (the actual percentage of PD in the PD-YES Centers)[18].

For this aspect, as for several others, the evaluation given by the Nephrologists in PD-TRANSF Centers is similar to that of those in PD-YES Centers.

Opinions: general factors conditioning modality selection

Fear of peritonitis is most felt in the PD-NO Centers, least in the PD-YES Centers and in between the two in the PD-TRANSF Centers. Of interest is the finding that the difference is no more significant when considering only the interviewees with > 3 years of experience with PD. Size of Center, less pressure on HD beds and closeness to private Centers are recognized as factors that favor or are indications for the use of HD with no significant differences between the Centers, while cost and shortage of nurses are indications for PD in the PD-YES and PD-TRANSF Centers, but not in the PD-NO Centers, where to the contrary for the majority they represent an indication for HD or have no importance. This may be justified by the different perspective Nephrologists have in different types of Center. In fact, though the nurses/patients ratio clearly favors PD, and therefore a shortage of nurses should represent an incentive for this method, the perspective taken in PD-NO Centers is of having to start a PD program with an initial investment which is known to always involve a greater use of resources rather than a saving, as becomes evident only after the program has started.

Opinions: patient-specific factors conditioning modality selection

While practically everyone agrees that diverticulosis and obesity are an indication for HD, that coronary artery disease is an indication for PD and that it makes no difference in the case of malnutrition and diabetes, there is no agreement on congestive heart failure (clear indication for PD in the PD-YES Centers) or polycystic nephropathy (clear indication for HD in the PD-YES and DP-TRANSF Centers). For the non-clinical factors, everyone agrees that motivation for self-care, having a work activity and the need for flexible treatment times are all indications for PD, while poor compliance is an indication for HD. The differences regard body image, which is considered an indication for HD in the PD-NO and TRANSF Centers while 50% in the PD-YES Centers are indifferent, and Quality of Life, which is considered better in PD by everyone, but even more positively in the PD-YES Centers. An age of between 65 and 75 is considered as making no difference or an indication for PD by the majority, while an age of over 75 and living alone are judged differently by those in the 3 types of Center. For the majority in the PD-NO Centers, being >75 years of age is an indication for HD, but not in the PD-YES Centers, while living alone represents an indication for HD for everyone, but much more so in the PD-NO Centers. However, if the patient is not self-sufficient and has a caregiver available PD is recognized by everyone as the recommended modality. Clearly, the availability of a caregiver is considered very rare in the PD-NO Centers. As regards possible incentives for PD, financial support for the caregiver or residential care facility is considered most important in the PD-YES Centers, while interestingly the most important for the interviewees in the PD-NO Centers are telemedicine and technological innovation.

PD-NO PD-TRANSF PD-YES
CHARACTERISTICS OF THE NEPHROLOGIST
existence of a structured choice pathway (YES, %) 47.2 55.2 73.2
involvement in all three pre-dialysis activities (%) 21.4 47.6 54.9
experience in PD of >3 years (%) 16.7 26.2 65.1
information on PD provided to pts on HD (score from 1 to 5) 2.8 3.3 3.7
THE CHOICE – ROLES
>40% of incident pts who could do PD (%) 28.6 45.2 74.3
NON marginal role of nurse in the choice (%) 14.3 31.0 60.5
THE VALUE OF PD
lower dialysis adequacy than HD (%) 57.1 35.7 25.7
lower survival rate than HD (%) 45.2 21.4 14.1
drop-out expected after 2 or 3 years (%) 33.3 23.9 14.3
optimal percentage of pts treated with PD of >30% 14.3 33.3 49.2
optimal percentage of pts treated with PD of <10% 21.4 2.4 0.3
FACTORS WHICH CONDITION THE CHOICE – indications for PD
cost (%) 41.0 59.5 57.0
shortage of nurses (%) 35.7 61.9 66.8
congestive heart failure (%) 40.4 42.9 60.6
Quality of Life (%) 47.6 54.8 67.2
pt not self-sufficient with caregiver available (%) 69.0 57.2 84.8
FACTORS WHICH CONDITION THE CHOICE – indications for HD
age > 75 years (%) 52.4 45.2 24.3
living alone (%) 76.2 81.0 51.6
ADPKD 59.5 83.3 41.1
body Image indication for HD 57.2 47.6 37.2
fear of peritonitis 48.8 20.0 15.5
Table 23. Summary of the main differences (considering only significant ones) of opinion between Nephrologists in the three types of Center.

 

Limitations of the study

The study has several limitations. The data were re-analyzed a number of years following their collection, so some findings linked to the time at which the survey was carried out may not have been highlighted or discussed. The prevalence and incidence data refer to 2004, and not to the year of the study. Finally, the participants were selected on a voluntary basis. However, the large size of the sample cohort, the inclusion of a substantial number of Nephrologists who do not prescribe PD and the different aspects considered undoubtedly represent a strength.

 

Conclusions

The study confirms the importance of the opinions or “preconceptions” of Nephrologists associated with the type of Center they work in. Compared with Centers in which PD is performed, in Centers in which it is not the opinion of PD is more negative, if there is a pre-dialysis choice pathway it is simplified to just providing information and the percentage of patients considered optimal for treatment with PD is lower. However, opinions vary in these Centers too (not everyone has the same view), conditioned as they are by the experience the Nephrologist has with PD, and can even be positive on various specific aspects. Together with the existence of Centers which send patients who may have an indication for PD to other Centers though they do not perform it themselves, as is highlighted for the first time by this study, all this suggests that the use of PD depends on a combination of structural factors (size, neighboring private facilities and HD beds) and opinions, in which the latter however are only partially conditioned by the former.

 

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Peritoneal Dialysis in Italy: the 8th GPDP-SIN Census 2022 – 2nd Part: the Centers

Abstract

Objectives. The results are presented of the 8th National Census (Cs-22) of the Peritoneal Dialysis Project Group of the Italian Society of Nephrology relating to the characteristics of the Centers in Italy which used PD in 2022.
Materials and methods. The 227 non-pediatric centers which used Peritoneal Dialysis (PD) in 2022 took part. The data requested were sent in aggregate form. For the first time, the resources available and training were investigated as well as home visits. The Centers have been divided into Quartiles according to the number of prevalent PD patients at 31/12/2022.
Results. Centers with a smaller PD program (<9 pts) are characterized by 1. smaller overall size – 2. fewer personnel (doctors/nurses) dedicated to PD – 3. greater recourse to external personnel for training – 4. Less incremental prescription and evaluation of peritoneal permeability – 5. higher drop-out to HD in particular for choice/impossibility to continue and for adequacy/catheter-related issues. A lower peritonitis rate was recorded in Centers with a more extensive PD program (≥25 pts). Home visits are carried out regularly by a small minority of Centers. Conclusions. The analysis shows an association between size of Center PD program and available resources, PD modality and outcome.

 

 

Graphical abstract

 

Keywords: Peritoneal Dialysis, Center effect, technique failure

Background

Besides results pertaining to peritoneal dialysis (PD), the Peritoneal Dialysis Project Group Census also investigates a number of organizational aspects, which were broadened in the last edition relating to 2022 to the resources available for PD (premises and dedicated personnel) and training. The PD results were published recently in this Journal [1]. In this second part, the characteristics are reported of the 227 Centers which used PD in 2022 and which have remained virtually the same over almost 20 years, in other words a minority of the Dialysis Centers in Italy.

The first Italian Society of Nephrology Census relating to 2004 had shown that PD was used in 64.3% of the non-pediatric public Centers (209 out of 325 Centers) and practically unused in all the 286 private Centers surveyed at the time. The use of PD was conditioned by whether the Center was public or private (absent in the latter), size of Center and HD bed occupancy (the greater the size and pressure on HD places, the greater the use of PD). In turn, the presence of private Centers ‒ significant in some areas ‒ reduces the size of the public Centers, reinforcing the negative effect on the use of PD.

However, there were large public Centers with a high HD bed occupancy rate which were not using PD, while it was used – even extensively – by others with opposite characteristics. Clearly, alongside the structural factors given there was also a fourth element conditioning the use of PD: the Center’s “policy”. This aspect was investigated by means of a 2007 questionnaire, also carried out by the PD Study Group, the results of which have never been published though. The methodology and breadth of the survey make it quite unique, still today. In an attempt to understand the state of affairs in Italy, it seemed to us only right to retrieve its results, attaching them to this paper.

 

Materials and methods

The methodology of the Census was described at great length in the recent paper published in this Journal, which can be referred to [1].

The characteristics of the Centers surveyed were the existence of premises for PD, the presence of medical and nursing personnel dedicated to PD (whose sole or exclusively attributed activity is PD), training methods in terms of both who performs it and where it is carried out, the performance of PET and lastly home visits.

As with other similar analyses, to facilitate the interpretation of the results the Centers have been divided into quartiles (Table 1) based on the number of prevalent patients on PD at 31/12/2022.

QUARTILE PREVALENT ON DP CENTERS %
MIN (from) MAX (to)
Q1 1 8 55 24,2
Q2 9 14 58 25,6
Q3 15 24 58 25,6
Q4 25 112 56 24,7
227  
Table 1. Division into quartiles of the 227 PD Centers surveyed based on number of prevalent patients on PD at December 31st 2022.

The groups were then compared for “structural” characteristics (size and percentage use of PD, geographical distribution, presence of dedicated personnel and spaces, training methods, home visits and performance of PET), for “use” of PD (manual or automated modality, incremental PD, assisted PD) and for “results” obtained (drop-out and turnover, peritonitis).

The Census represents a snapshot of the situation relating to PD in Italy. The statistical analysis (chi-square) was therefore limited to any differences between the groups.

 

Results

STRUCTURAL CHARACTERISTICS OF THE CENTERS

Size of Center and percentage use of PD

Table 2 shows the structural characteristics of the Centers divided into the 4 quartiles of PD prevalence.

The size of Centers was assessed by considering the total number of dialysis patients (HD + PD) at 31/12/2022, and as a result limited to the 183 Centers which provided HD prevalence data. As can be seen (Table 2), as the overall size of the Center increases, not only the number but also the percent proportion of PD patients with respect to total dialysis patients rise from 6.5% in Centers with a minimal PD program (Q1, 1-8 PD patients per Center) to 20.9% in “large” Centers (Q4, ≥25 patients).

Although it is not certain, the estimate can be considered valid as the number of PD patients per Center (“PD PTS per CENTER”) is practically superimposable on those recorded in all 227 Centers (Table 2).

ALL PD CENTERS CENTERS WITH HD PREVALENCE AVAILABLE
CENTERS PD

PREVAL.

PD PTS per CENTER CENTERS PD

PREVAL.

HD

PREVAL.

PD PTS per CENTER HD PTS per CENTER TOT PTS per CENTER %PD
Q1 55 265 4.8 45 213 3063 4.7 68.1 72.8 6.5
Q2 58 662 11.4 46 535 4466 11.6 97.1 108.7 10.7
Q3 58 1124 19.4 47 903 5134 19.2 109.2 128.4 15.0
Q4 56 2101 37.5 45 1661 6279 36.9 139.5 176.4 20.9
ITALY 227 4152 18.3 183 3312 18942 18.1 103.5 121.6 14.9
Table 2. Percentage use of PD and size of Center. The analysis was only possible for the 183 Centers which provided HD prevalence data. The missing Centers were equally distributed among the 4 groups, and the size of PD program was found to be practically superimposable (“PD PTS per CENTER”). The overall size of the Center is given in the “TOT PTS per CENTER” column: the sum of HD and PD prevalent patients.

The distribution of the Centers in Figure 1 shows how there are some significantly-sized Centers where the use of PD is limited, and other smaller Centers using it in a high percentage of patients, confirming the finding of the first SIN Census.

Distribution of the 183 Centers which also provided HD data. PD prevalence by size of Center
Figure 1. Distribution of the 183 Centers which also provided HD data. PD prevalence by size of Center (HD and PD). The lines define the quartiles of the 2 variables.

Geographical distribution

The geographical breakdown of the Centers by size, which was already partly analyzed in the previous paper, shows how PD programs are more widespread in Centers in the North.

While the number of the Centers using PD per million inhabitants (pmp) is practically superimposable (Table 3), varying only a little from the national average of 3.9 PD Centers pmp, those located in the NORTH follow a greater number of patients (21.9 ±16.5 patients per Center) than the others. It follows that PD prevalence pmp in the NORTH (81.7 PD patients pmp) is also higher than in the Centers in Central Italy (72.9 PD patients pmp) and in the SOUTH and ISLANDS where it is practically identical (55.22 and 55-20 PD patients pmp respectively) (Table 3). However, an examination of the Centers which also sent data for HD confirm (Table 4) the finding of some 20 years ago. The Centers in the SOUTH and ISLANDS which use PD are on average smaller, in terms of both overall size and PD program, but with a higher percentage of PD patients (Table 4).

PD PREVAL. per CENTER
CENTERS
(no.)
POPULATION
(inhabit.)
PD PREVAL.
(no of pts)
PD PREVAL.
(pmp)
CENTERS
(pmp)
MEAN (±DS)
(no. of pts)
MEDIAN
(no. of pts)
NORTH 102 27,349,747 2235 81.7 3.7 21.9±16.5 19
CENTER 54 11,693,240 853 72.9 4.6 15.8±12.0 12
SOUTH 47 12,894,027 712 55.2 3.6 15.1±13.1 13
ISLANDS 24 6,377,044 352 55.2 3.8 14.7±13.9 10
ITALY 227 58,314,058 4152 71.2 3.9 3.3    ±14.8 15
Table 3. Geographical distribution of the Centers in the 4 macro regions of Italy and their size of PD program. The regional breakdown and population are 2022 ISTAT (Italian National Institute of Statistics) data, the prevalence is at 31/12/2022.  pmp = per million population; THE REGIONS OF ITALY AS DEFINED BY ISTAT – NORTH = Valle d’Aosta, Piemonte, Lombardia, Trentino Alto Adige, Friuli Venezia Giulia, Veneto, Emilia Romagna, Liguria – CENTER = Toscana, Marche, Umbria, Lazio – SOUTH = Abruzzo, Molise, Puglia, Campania, Basilicata, Calabria – ISLANDS = Sicily, Sardinia.
CENTERS PREVALENCE (no.)
no. % HD PD SIZE PD/CENTER %PD
NORTH 83 81.4 11588 1751 160.7 21.1 13.1
CENTER 51 94.4 4210 821 98.6 16.1 16.3
SOUTH 29 61.7 2057 443 86.2 15.3 17.7
ISLANDS 20 83.3 1087 297 69.2 14.9 21.5
ITALY 183 80.6 18942 3312 121.6 18.1 14.9
Table 4. Characteristics of the Centers in the 4 macro areas of Italy which also sent data relating to HD. “SIZE” = total number of patients (HD+PD) on dialysis at 31/12/2022 – “PD/CENTER” = prevalent PD patients per Center – “%PD” = mean percentage PD prevalence in the Centers.

Resources dedicated to PD

Most of the Centers (95.1%) have facilities dedicated to PD whatever the size of their PD program, while there are significant differences with regard to the personnel – both medical and nursing – dedicated to PD (Table 5).

In particular, nearly half the small Centers (48.1%) have no one member of staff – either medical or nursing – as a point of reference (“everyone can handle PD as well”). This percentage drops to 12.5% in the Centers with an extensive PD program (Table 5).

CENTERS FACILITIES DOCTORS NURSES BOTH NONE DOCTOR OR NURSE (%)
Q1 54* 49 20 23 15 26 51.9
Q2 58 54 19 30 17 26 55.2
Q3 57* 56 32 44 31 12 78.9
Q4 56 55 36 45 41 7 87.5
ITALY 225 214 107 142 104 71 68.4
NS p<0.005 p<0.00005     p<0.00005
Table 5. Resources for PD in the 227 Centers which use it. For the personnel, dedicated professionals are considered to be doctors and nurses who are engaged exclusively with PD, but also those who, in particular in the “small” Centers, are assigned the exclusive task of handling it. “Both” refers to the Centers where there are both medical and nursing personnel dedicated to PD (the difference between “Doctors” plus “Nurses” and “Both” provides the number of Centers which have only the Doctor or Nurse as dedicated PD professional). “None” refers to the Centers which have no dedicated PD professionals. * Two Centers (Q1 and Q3) did not provide information on Training.

Activities

The activities considered by the Census are training, home visits and the performance of PET.

Training. Training is carried out by in-Center personnel in 57.3% of the Centers, by external personnel in 11.6% and by both in 31.1%. The contribution of external personnel is lower in the large and medium-small Centers (Q4 and Q2, 26.8% and 41.4% of Centers respectively) and greater in the Centers with a small or medium-large PD program (Q1 and Q3, 51.9% and 50.9% of Centers respectively) (Table 6). The place where the training takes place more frequently is the Center (52.4% of cases), partly at home and partly in the Center in 37.8% of cases and only at home in 9.8% of the Centers (Table 6). The location of the training depends on the provider. In fact, when the training is performed by in-house personnel (57.3% of the Centers) it takes place mostly in the Hospital (80.6% of cases), while in the Centers in which only or partly external personnel are involved (42.7% of the Centers) the training is performed exclusively or partly at home (85.4% of the Centers, p<0.000001) (Figure 2).

PROVIDER PLACE OF TRAINING
CENTERS CENTER EXTERNAL BOTH % CENTER CENTER HOME BOTH % HOME
Q1 54* 26 7 21 48.1 27 5 22 50.0
Q2 58 34 11 13 58.6 36 5 17 37.9
Q3 57* 28 5 24 49.1 20 6 31 64.9
Q4 56 41 3 12 73.2 35 6 15 37.5
ITALY 225 129 26 70 57.3 118 22 85 47.6
p<0.03 p<0.001
Table 6. The Provider and Place where the Training takes place. The Provider can be “Center” personnel only, “External” personnel only, or “Both” if it is performed in the Center by both in-house and external personnel. The absolute values and percentages refer to the Centers and NOT to the number of Trainings.* Two Centers did not provide information on Training. “% CENTER” is the percentage of Centers in which the Training is performed by in-house personnel. “% HOME” is the percentage of Centers which perform the Training exclusively or partly at home.
Figure 2. Training divided by provider.
Figure 2. Training divided by provider. The place (home, hospital or both) where it is carried out is given for each provider.

Home visits. The home visits (HV) program once the PD has started is in keeping with training practice. They are not envisaged by the majority of the Centers (55.2%), with no significant differences between the 4 groups (Table 7), while only a minority of the remainder carry them out regularly following a pre-defined program (8.5%). In the other Centers they are basically performed when necessary. With respect to previous years, the percentage of the Centers with no HV program once PD has started has increased (48.5% in 2016), while the percentage of the number of the Centers with a regular HV program remains unchanged, as an absolute value as well (Figure 3).

FREQUENCY OF HOME VISITS
CENTERS NOT ENVISAGED VARIABLE REGULAR % NO
Q1 53 25 25 3 47.2
Q2 57 32 21 4 56.1
Q3 57 30 22 5 52.6
Q4 56 36 13 7 64.3
ITALY 223 123 81 19 55.2
Table 7. Frequency of home visits after PD has started. The question was answered by 223 of the 227 Centers considered. The difference between the groups was NOT significant. Variable frequency is to be understood as meaning “only during the initial period”, which was not further specified, “at the start when needed” and lastly “only if necessary”. “Not envisaged” means they are not considered by the Center for PD follow-up.
Figure 3. Home visits over time.
Figure 3. Home visits over time. The data relating to 2019 are incomplete. The home visits considered are those carried out once PD has started, i.e. excluding those during training.

PET. Evaluation of the peritoneal membrane by PET is not performed by 11.9% of the Centers, mostly the smaller ones (NO PET – Q1 = 18.2%; Q2 = 13.8%; Q3 = 12.1%; Q4 = 3.6% – p = N.S.), although the difference is not statistically significant.

PD MODALITY

CAPD/APD and incremental PD in incident patients

Overall, the most used PD modality in incident patients is CAPD (52.1%), but with a significant difference between the groups according to size of PD program: the smaller Centers mostly use APD, while CAPD is the most widely-used modality in the larger Centers (p<0.005). This is partly associated with incremental prescription, for which CAPD is preferred, with its use rising as size of Center increases (Table 8). Lastly, admissions from HD and Tx increase (percentage-wise with respect to total admissions) as PD program size grows, although not significantly.

INCIDENT PATIENTS OTHER ADMISSIONS
CENTERS CAPD APD TOT % CAPD INCR % INCR from HD/Tx TOT IN % from HD/Tx
Q1 55 38 54 92 41,3 25 27,2 12 104 11,5
Q2 58 104 120 224 46,4 65 29,0 33 257 12,8
Q3 58 240 164 404 59,4 170 42,1 55 459 12,0
Q4 56 321 309 630 51,0 217 34,4 126 756 16,7
ITALIA 227 703 647 1350 52,1 477 35,3 226 1576 14,3
P<0,005 P<0,005 N.S.
Table 8. PD modality (CAPD and APD) and incremental prescription (“INCR”) at the start of treatment by size of PD program. On the right, admissions from HD and transplant (Tx), and their percentage weight on the total of admissions to PD recorded in 2022.

The percentage of late referrals to PD was shown NOT to differ significantly among the groups (Q1 = 5.4% – Q2 = 8.0% – Q3 = 11.4% – Q4 = 7.9% – p = N.S.)

CAPD/APD and assisted PD in prevalent patients

APD is confirmed as the most used PD modality for prevalent patients, but ‒ as with incident patients ‒ significantly more so in the smaller Centers (Table 9). Recourse to assisted PD, on the other hand, is greater in the smaller Centers, in particular in the second quartile compared to the fourth. Overall it is used in 26% of prevalent patients in the Centers with fewer than 15 prevalent PD patients, and in 19.8% of patients in the Centers with a higher prevalence.

No significant difference emerged between the Quartiles with regard to type of caregiver, with a family member being confirmed as the most commonly-involved caregiver in Italy (86.3%) (Table 9).

PREVALENT PTS – TYPE OF PD PREVALENT PTS – ASSISTED PD
CENTERS CAPD APD TOT % CAPD RSA FAM. CARER IP TOT ASS. PD % ASS. PD
Q1 55 98 167 265 37.0 3 47 2 5 57 21.5
Q2 58 261 401 662 39.4 2 165 14 3 184 27.8
Q3 58 513 611 1124 45.6 20 212 18 2 252 22.4
Q4 56 931 1170 2101 44.3 15 334 31 5 385 18.3
ITALY 227 1803 2349 4152 43.4 40 758 65 15 878 21.1
p<0.01 N.S. p<0.0001
Table 9. PD modality (CAPD and APD) and assisted PD in prevalent PD patients at 31/12/2022. “RSA” = nursing home, facility for the elderly – “FAM.” = family-member caregiver– “CARER” = live-in carer, paid assistant – “IP” = nurse (or other healthcare worker) who performs the dialysis at the patient’s home – “% ASS. PD” represents the percentage of prevalent patients on assisted PD.

OUTCOME

Peritonitis

Although the incidence of peritonitis was lower in the larger Centers, it was substantially superimposable. The percentage of negative cultures was not significantly different either (Table 10).

CENTERS PERITONITIS INCIDENCE NEGATIVE % NEGATIVE
Q1 54 50 0.186 7 14.0
Q2 58 115 0.185 23 20.0
Q3 58 221 0.209 35 15.8
Q4 56 310 0.156 69 22.3
ITALY 226 696 0.176 134 19.3
Table 10. Episodes of peritonitis (total and culture-negative peritonitis) and size of Centers. The peritonitis rate is expressed as episodes per patient year. “% NEGATIVE” is the percentage of culture-negative peritonitis out of total episodes (N.S.). Only one Center did not provide data on peritonitis.

Drop-out from PD

The average duration of PD, taken from the Replacement Index (ratio between Prevalent patients at 31/12/2022 and all admissions recorded in 2022, expressed in years) was higher in the larger Centers (RI – Q1 = 2.5 equivalent to 30.6 months; Q2 = 2.6 equivalent to 30.9 months; Q3 = 2.4 equivalent to 29.4 months; Q4 = 2.8 equivalent to 33.3 months).

Causes of drop-out from PD. In 2022 a total of 464 patients were transferred to HD, 400 died and 296 received a transplant for a total of 29.3 drop-outs from PD per 100 patient-years. Mortality was significantly different, while a higher number of transplants and in particular Drop-Outs to HD were recorded in small Centers (Table 11).

EVENTS EVENTS / 100 PT-YEARS
CENTERS PREV. TRANSF DEATH TX D-O DEATH TX
Q1 55 265 64 30 35 22.9 10.8 12.5
Q2 58 662 80 49 49 12.9 7.9 7.9
Q3 58 1124 140 120 61 13.2 11.3 5.8
Q4 56 2101 180 201 151 9.0 10.1 7.6
ITALY 227 4152 464 400 296 11.7 10.1 7.5
p<0.00001 N.S. p<0.001
Table 11. Drop-out from PD due to transfer to HD (TRANSF), death and transplant (Tx) during 2022 divided by size of Centers.

As regards the specific causes of transfer to HD, in the small Centers (subject to a higher drop-out to HD) the main cause is choice or impossibility to continue, followed by catheter and dialysis adequacy issues. Confirming the validity of this is peritonitis as cause of drop-out which, like incidence of peritonitis, is also essentially superimposable in the different quartiles (Table 12).

EVENTS ep/100 pt-years
CENTERS TOT. TRANSF PERITON. CAT./ADEQ, CH./IMP. PERITON. CAT./ADEQ. CH./IMP.
Q1 55 64 9 27 28 3.2 9.7 10.0
Q2 58 80 22 37 21 3.5 6.0 3.4
Q3 58 140 25 60 55 2.4 5.7 5.2
Q4 56 180 53 76 51 2.7 3.8 2.6
ITALY 227 464 109 200 155 2.8 5.1 3.9
p<0.05
Table 12. Drop-out from PD for transfer to HD (TRANSF), death and transplant (Tx) during 2022 divided by size of Centers. “PERITON:” = peritonitis; “CAT./ADEQ.” = malfunctioning or infected catheter/adequacy both clearance and UF;“CH./IMP.” = choice or impossibility to continue.

 

Discussion

The limitations of the Census were already extensively discussed in part one [1].

The results of the 2022 Census confirm the findings of the first SIN Census in 2004. The use of PD is proportional in percentage terms to the size of Center and, as emerges from the geographical distribution of the Centers, lower wherever there are more private Centers, although the few Centers which do use it in these regions do so to a greater than average extent (see Annex – Questionnaire).

From an organizational point of view, smaller Centers are characterized first and foremost by fewer personnel dedicated to PD, either exclusively or – in the smaller Centers – as PD point of reference even though they certainly (Annex – Questionnaire) perform other activities. In the Centers in which there are no dedicated personnel, the “everyone does everything” principle most probably applies and in the end recourse to external personnel is necessary for training, the most important part of a PD program. Indeed, the Centers with a limited PD program rely more for training on external personnel, whose role – if any – in PD patient follow up was not however investigated. Though a positive aspect of training performed by external personnel or in combination is that it is carried out at home, this ends up “separating” PD patients even more from their Center. Lastly, another characteristic of the Centers with a limited PD program is less incremental prescription, and therefore greater use of APD.

Finally it is confirmed how home visits after starting on PD are carried out regularly only by a tiny minority of Centers.

Mortality is substantially superimposable in the different groups, while drop-out to HD is significantly higher in the Centers with a modest PD program, in which the main cause of drop-out to HD is patient choice and/or impossibility to continue. The latter term however, as discussed in the first part, is ambiguous as it can refer not only to loss of self-sufficiency but also clinical causes, to which inaccurate patient selection or insufficient follow up can contribute. Drop-out for adequacy due to catheter-related causes is also higher in smaller Centers. Peritonitis rates seem to be lower in the Centers with an extensive PD program, but drop-out for this cause is substantially similar.

 

Conclusions

In the public Centers in Italy which use PD the resources deployed, the modality of use and drop-out are associated (negatively) with size of PD program. In turn, the size of PD program is influenced by well-known factors which, as illustrated in “The Questionnaire” annex also condition – though only partly – the opinions Nephrologists in Centers not using PD have of this modality. There are therefore many reasons for the limited use of PD which are not justified by the results obtained and its potential, or by the prospect of having to treat increasingly fragile patients with ever more limited resources.

 

Acknowledgements

We thank the contacts in the Centers which took part in the Census and whose commitment made the collection of the data and this paper possible:

Abdulsattar Giamila (Oristano); Alberghini Elena (Cinisello Balsamo); Albrizio Paolo (Voghera); Alessandrello Maria Grazia Ivana (Modica); Alfano Gaetano (Modena); Amar Karen (Cernusco sul Naviglio); Ambrogio Antonina (Rovigo); Ancarani Paolo (Sestri Levante); Angelini Maria Laura (forlì); Ansali Ferruccio (Civitavecchia); Apponi Francesca (Frosinone); Argentino Gennaro (Napoli); Avella Alessandro (Varese); Barattini Marina (Massa); Barbera Vincenzo (Colleferro); Basso Anna (Padova); Bellotti Giovanni (Sapri); Benozzi Luisa (Borgomanero); Bermond Francesca (Torino); Bianco Beatrice (Verona); Bigatti Giada (Sesto San Giovanni); Bilucaglia Donatella (Torino); Boccadoro Roberto (Rimini); Boito Rosalia (Crotone); Bonesso Cristina (San Donà di Piave); Bonincontro Maria Luisa (Bolzano); Bonvegna Francesca (Verbania); Borettaz Ilaria (Melegnano – Vizzolo Predabissi); Borrelli Silvio (Napoli); Bosco Manuela (Gorizia); Braccagni Beatrice (Poggibonsi); Budetta Fernando (Eboli); Cabibbe Mara (Milano); Cabiddu Gianfranca (Cagliari); Cadoni Maria Chiara (San Gavino Monreale); Campolo Maria Angela (Lamezia Terme); Cannarile Daniela Cecilia (Bologna); Cannavo’ Rossella (Firenze); Canonici Marta (Fabriano); Cantarelli Chiara (Parma); Caponetto Carmelo (Siracusa); Cappadona Francesca (Genova); Cappelletti Francesca (Siena); Caprioli Raffaele (Pisa); Capurro De Mauri Federica Andreana (Novara); Caria Simonetta (Quartu Sant’ Elena); Carta Annalisa (Nuoro); Caselli Gian Marco (Firenze); Casuscelli di Tocco Teresa (Messina); Cataldo Emanuela (Altamura); Cernaro Valeria (Messina); Cerroni Franca (Rieti); Ciabattoni Marzia (Savona); Cianfrone Paola (catanzaro); Cimolino Michele (Pordenone); Comegna Carmela (Tivoli); Consaga Marina (Livorno); Contaldo Gina (Monza); Conti Paolo (Arezzo); Cornacchia Flavia (Cremona); Cosa Francesco (Legnano); Cosentini Vincenzo (San Bonifacio); Costantini Luigia (Vercelli); Costantino Ester Grazia Maria (Manerbio); Costanza Giuseppa (Gela); D’Alonzo Silvia (Roma); D’Altri Christian (Martina Franca); D’Amico Maria (Erice); De Blasio Antonietta (Caserta); Del Corso Claudia (Pescia); Della Gatta Carmine (Nola); D’Ercole Martina (La Spezia); Di Franco Antonella (Barletta); Di Liberato Lorenzo (Chieti); Di Loreto Ermanno (Atri); Di Renzo Brigida (Brindisi); Di Somma Agnese (San Marco Argentano); Di Stante Silvio (Pesaro – Fano); Dinnella Angela Maria (Anzio); Distratis Cosimo (Manduria); Dodoi Diana Teodora (Chieri); Domenici Alessandro (Roma); Esposito Samantha (Grosseto); Esposito Vittoria (Pavia); Farina Marco (Lodi); Ferrando Carlo (Cuneo); Ferrannini Michele (Roma); Ferrara Gaetano (San Giovanni Rotondo); Figliano Ivania Maria (Vibo Valentia); Figliola Carmela (Gallarate); Filippini Armando (Roma); Finato Viviana (San Miniato); Fiorenza Saverio (Imola); Frattarelli Daniele (Roma Ostia); Gabrielli Danila (Aosta); Gai Massimo (Torino); Garofalo Donato (Fermo); Gazo Antonietta (Vigevano); Gennarini Alessia (Bergamo); Gherzi Maurizio (Ceva); Giancaspro Vincenzo (Molfetta); Gianni Glauco (Prato); Giovannetti Elisabetta (Camaiore); Giovannetti Elisabetta (Lido di Camaiore); Giozzet Morena (Feltre); Giuliani Anna (Vicenza); Giunta Federica (Macerata); Graziani Romina (Ravenna); Guizzo Marta (Castelfranco Veneto); Heidempergher Marco (Milano); Iacono Rossella (Civita Castellana); Iadarola Gian Maria (Torino); Iannuzzella Francesco (Reggio Emilia); Incalcaterra Francesca (Palermo); La Milia Vincenzo (Lecco); Laudadio Giorgio (Bassano del Grappa); Laudon Alessandro (Trento); Lenci Federica (Ancona); Leonardi Sabina (Trieste); Lepori Gianmario (Olbia); Leveque Alessandro (Citta’ di Castello); Licciardello Daniela (Acireale); Lidestri Vincenzo (Chioggia); Lisi Lucia (Vimercate); Lo Cicero Antonina (San Daniele del Friuli ); Luciani Remo (Roma); Maffei Stefano (Asti); Magnoni Giacomo (Bologna); Malandra Rossella (Teramo); Manca Rizza Giovanni (Pontedera); Mancuso Verdiana (Agrigento); Manfrini Vania (Seriate); Manini Alessandra (Crema); Marcantoni Carmelita (Catania); Marchetti Valentina (Lucca); Marini Alvaro (Popoli); Martella Vilma (Lecce); Masa Maria Alessandra (Sondrio); Mastrippolito Silvia (Lanciano); Mastrosimone Stefania (Treviso); Matalone Massimo (Catania); Mauro Teresa (Corigliano Rossano); Mazzola Giuseppe (Mantova); Melfa Gianvincenzo (Como); Messina Antonina (Catania); Miglio Roberta (Busto Arsizio); Miniello Vincenzo (Pistoia); Mollica Agata (Cosenza); Montalto Gaetano (Taormina); Montanari Marco (Ariccia); Montemurro Vincenzo (Firenze); Musone Dario (Formia); Nardelli Luca (Milano); Neri Loris (Alba); Orani Maria Antonietta (Milano); Palmiero Giuseppe (Napoli); Palumbo Roberto (Roma); Panuccio Vincenzo Antonio (Reggio Calabria); Panzino Antonio Rosario (Catanzaro); Parodi Denise (Arenzano); Pastorino Nadia Rosa (Novi Ligure); Pellegrino Cinzia (Cetraro); Perilli Luciana (Vasto); Perna Concetta (Cerignola); Perosa Paolo (Pinerolo); Pieracci Laura (Imperia); Pietanza Stefania (Putignano); Pignone Eugenia (Torino); Pinerolo Maria Cristina (Milano); Piraina Valentina (ivrea); Pirrottina Maria Anna (San Benedetto del Tronto); Pisani Antonio (Napoli); Pogliani Daniela Rosa Maria (Garbagnate Milanese); Porreca Silvia (Bari); Pozzi Marco (Desio); Prerez Giuseppina (Dolo); Previti Antonino (Santorso); Puliti Maria Laura (Palestrina); Randone Salvatore (Avola); Ricciardi Daniela (Castiglione del Lago); Ricciatti Annamaria (Ancona); Rocca Anna Rachele (Roma); Rubini Camilla (Venezia Mestre); Russo Francesco Giovanni (Scorrano); Russo Roberto (Bari); Sabatino Stefania  (Udine); Sacco Colombano (Biella); Sammartino Fulvio Antonio (Pescara); Santarelli Stefano (Jesi); Santese Domenico (Taranto); Santinello Irene (Piove di Sacco); Santirosi Paola Vittori (Foligno-Spoleto); Santoferrara Angelo (Civitanova Marche); Saraniti Antonello (Milazzo); Savi Umberto (Belluno); Scalso Berta Ida (Cirie’); Scarfia Rosalia Viviana (Caltagirone); Serriello Ilaria (Roma); Signorotti Sara (Cesena); Silvana Baranello (Campobasso); Somma Giovanni (Castellamare di Stabia); Sorice Mario (Senigallia); Spissu Valentina (Sassari); Stacchiotti Lorella (Giulianova); Stucchi Andrea (Milano); Taietti Carlo (Treviglio); Tata Salvatore (Venezia); Teri Antonino (Foggia); Tettamanzi Fabio (Tradate); Timio Francesca (Perugia); Todaro Ignazio (Piazza Armerina); Toriello Gianpiero (Polla); Torraca Serena (Salerno); Trepiccione Francesco (Napoli); Trubian Alessandra (Legnago); Turchetta Luigi (Cassino); Vaccaro Valentino (Alessandria); Valsania Teresa (Piacenza); Vecchi Luigi (Terni); Veronesi Marco (Ferrara); Visciano Bianca (Magenta); Viscione Michelangelo (Avellino); Vizzardi Valerio (Brescia); Zanchettin Gianantonio (Conegliano); Zeiler Matthias (Ascoli Piceno).

 

Bibliography

  1. Neri L, Viglino G, Vizzardi V, Porreca S, Mastropaolo C, Marinangeli G, Cabiddu G. Peritoneal Dialysis in Italy: the 8th GPDP-SIN census 2022. G Ital Nefrol. 2023 Jun 29;40(3):2023-vol3. PMID: 37427898.
  2. Viglino G, Neri L, Alloatti S, Cabiddu G, Cocchi R, Limido A, Marinangeli G, Russo R, Teatini U, Schena FP. Analysis of the factors conditioning the diffusion of peritoneal dialysis in Italy. Nephrol Dial Transplant. 2007 Dec;22(12):3601-5. https://doi.org/10.1093/ndt/gfm416.

West Nile Infection and Kidney Disease: Description of Two Clinical Cases in Peritoneal Dialysis Patients

Abstract

The West Nile Virus (WNV), an RNA arbovirus, has been transmitted by wild birds and conveyed by ticks and mosquitoes, with wide diffusion all over the world; it is not transmitted from human to human. It can give clinical symptoms only in a minority of infected subjects such as fever, headache, muscle tiredness, visual disturbances, drowsiness, convulsions and muscle paralysis; in the most serious cases even potentially fatal encephalitis. In the literature there are few reports on WNV infection in patients with kidney diseases: here we report our experience on two patients on peritoneal dialysis infected by WNV with a revision of the literature.

Keywords: West Nile virus infection, chronic kidney disease, end-stage kidney failure, peritoneal dialysis, kidney transplant

Sorry, this entry is only available in Italian.

Introduzione

Il virus del Nilo occidentale (West Nile VirusWNV) (Figura 1), un arbovirus a RNA, fu isolato per la prima volta in Uganda nel 1937 e in seguito si è diffuso in Europa, Asia e Australia. Nel 1996, la prima grande epidemia europea si è verificata in Romania, seguita successivamente da diverse epidemie in vari paesi dell’Eurasia, dove i virus sono attualmente endemici. Nel 1999, il WNV ha raggiunto il continente nordamericano, dove negli USA si è diffuso rapidamente diventando endemico con circa 3 milioni di individui infetti nel 2010 (780.000 che hanno manifestato la malattia) [1, 2].

Il WNV si manifesta in due distinti gruppi, l’1 e il 2, con ceppi diversi, ed è ospite di uccelli selvatici; è veicolato da zecche e zanzare e non si trasmette da uomo a uomo.

La potenziale trasmissione per via orale in un uccello predatore può spiegare la diffusione relativamente rapida del WNV, così come di altri flavivirus caratterizzati da modelli di trasmissione simili [3].

In meno dell’1% dei casi, il WNV può provocare manifestazioni neurologiche, caratterizzate da una mortalità del 10% con meningite, encefalite, paralisi flaccida acuta simile alla poliomielite e sindrome simile a Guillain-Barré. I fattori di rischio associati a peggior prognosi sono la malattia renale cronica (MRC), il cancro, l’abuso di alcol, l’ipertensione, il diabete, l’età avanzata e l’immunosoppressione [4].

Il WNV può essere trovato dopo l’infezione in vari tessuti quali cervello, linfonodi, milza e reni: il virus è stato costantemente rilevato nelle urine di pazienti durante l’infezione acuta, persistendo per un tempo più lungo rispetto al sangue. La presenza di antigeni WNV è stata rilevata anche nel rene nelle autopsie di pazienti trapiantati colpiti da WNV [5]. 

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Contrast Induced Encephalopathy after carotid percutaneous transluminal angioplasty in a patient with end stage renal disease undergoing peritoneal Dialysis

Abstract

Introduction. Contrast Induced Encephalopathy (CIE) belongs to Major Adverse Renal and Cardiovascular Events (MARCE) after iodinated contrast medium (IOCM), especially for high-risk patients with several comorbidities such as hypertension, diabetes, heart failure, and Chronic Kidney Disease (CKD). We report a case of CIE in a Peritoneal Dialysis (PD)-patient.
Case report. A 78-year-old, affected by diabetes, hypertension, chronic heart failure, and End Stage Renal Disease (ESRD) treated with PD, underwent a carotid Percutaneous Angioplasty (PTA). Immediately after the exam, he developed mental confusion and aphasia. Encephalic CT scan and MRI excluded acute ischemia or hemorrhage but showed cerebral oedema.  Mannitol and steroids were administered and additional PD exchange was performed with depurative aim. Within 2 days the patient completely recovered.
Discussion. CIE mimics severe neurological diseases. It should be considered as a differential diagnosis if symptoms occur immediately after administration of IOCM, especially in high-risk patients and in case of intra-arterial injection. Clinical presentation includes transient cortical blindness, aphasia, focal neurological defects, and confusion. CIE is often a diagnosis of exclusion, and imaging plays a significant role. Symptoms generally resolve spontaneously within 24-48h, rarely in few days. Symptomatic therapy, including mannitol and steroids could be considered. In literature, CIE is reported only in a few patients affected by ESRD treated with chronic HD, and our is the first available case of a patient treated with chronic PD who developed this rare complication.

Keywords: Peritoneal Dialysis, Contrast-induced encephalopathy, contrast medium

Sorry, this entry is only available in Italian.

Introduzione

I mezzi di contrasto organo-iodati (Iodinated Contrast Medium, IOCM) sono largamente utilizzati per procedure diagnostiche e interventistiche. È risaputo che il loro uso si associa ad un aumentato rischio di eventi avversi maggiori cardiovascolari e renali (Major Adverse Renal and Cardiovascular Events, MARCE), soprattutto nelle persone ad alto rischio per la presenza di più comorbidità, come ipertensione arteriosa, diabete mellito, scompenso cardiaco e insufficienza renale cronica (Chronic Kidney Disease, CKD).
I MARCE comprendono sia eventi maggiori renali (Major Adverse Kidney Events, MAKE) – che includono il peggioramento della funzione renale, la necessità di avvio del trattamento dialitico – sia eventi cardiovascolari maggiori (MACE, Major Adverse Cardiac Event) tra cui l’infarto miocardico, l’ictus, lo scompenso cardiaco, fino al decesso [1].
Il rischio di eventi avversi si è dimostrato significativamente più basso con volumi minori di mezzo di contrasto, utilizzando mezzi di contrasto iso-osmolari, rispetto a mezzi di contrasto di tipo ipo- o iper-osmolare, e in caso di somministrazione endovenosa piuttosto che intra arteriosa: tale rischio è aumentato per i pazienti con funzione renale già compromessa e/o diabete [24].
Tra gli eventi avversi maggiori legati all’utilizzo di IOCM più rari, ma potenzialmente gravi, vi è l’encefalopatia indotta da mezzo di contrasto (Contrast-Induced Encefalopathy, CIE) [5, 6].
Durante un episodio di CIE i pazienti possono sviluppare un’ampia gamma di deficit neurologici: il più frequente è rappresentato dalla cecità transitoria corticale, afasia, deficit neurologici focali, confusione, simulando quindi la clinica tipica dello stroke, a cui si potrebbe aggiungere il rialzo termico. La sintomatologia nella maggior parte dei casi si risolve entro 24-48 ore, meno spesso, entro pochi giorni [6], in rari casi i danni possono essere permanenti [7].
Nel presente lavoro riportiamo un caso di CIE a seguito dell’utilizzo di IOCM intra arterioso durante una procedura di angioplastica di stenosi carotidea in un paziente affetto da diabete mellito, ipertensione arteriosa, scompenso cardiaco ed insufficienza renale cronica in fase uremica (End Stage Renal Disease, ESRD) in trattamento dialitico peritoneale (Peritoneal Dialysis, PD) cronico.
Limitatamente alle nostre conoscenze, si tratta del primo caso riportato in letteratura di paziente con ESRD trattato con PD cronica che abbia sviluppato questa rara complicanza.

 

Caso clinico

Riportiamo un caso clinico di un paziente di 78 anni, di etnia caucasica, affetto da ESRD secondaria a nefropatia diabetica con diuresi ancora conservata, in trattamento con Continuous Cycling Peritoneal Dialysis (CCPD1) da dicembre 2019 presso il nostro centro di dialisi peritoneale. Lo schema dialitico domiciliare prevedeva l’utilizzo di 9,5 L di dialisato (agente osmotico: Glucosio 1,36%) per la dialisi automatizzata notturna e 1 scambio diurno con 1,5 L (agente osmotico: Icodestrina 7,5%); l’ultrafiltrazione media giornaliera era pari circa a 1 L, e la diuresi residua media giornaliera era pari a circa 1 L. In anamnesi patologica prossima si documentava un ricovero di circa sei mesi prima per polmonite da SARS-CoV-2 successivamente complicata da peritonite sterile. Tra le principali comorbidità si identificavano l’ipertensione arteriosa, scompenso cardiaco cronico secondario a cardiopatia ischemica e pregressi attacchi ischemici cerebrali transitori (TIA). Non erano documentate precedenti allergie.

Il paziente veniva ricoverato nel nostro reparto per una peritonite polimicrobica de novo (dagli esami colturali del liquido peritoneale venivano isolati Escherichia Coli, Enterococcus Faecalis, Klebsiella Pneumoniae), trattata con terapia antibiotica endovenosa (Piperacillina/Tazobactam e Linezolid) ed intraperitoneale (Ceftazidime e Vancomicina) ottenendo una buona risposta clinica e laboratoristica. Durante il ricovero lo schema dialitico prevedeva tre scambi di Continuous Ambulatory Peritoneal Dialysis (CAPD) di cui due diurni con agente osmotico Glucosio 1,36% (2 L per scambio) e uno notturno con 1,5 L (agente osmotico: Icodestrina 7,5%). Il ricovero veniva complicato da un infarto NSTEMI (Non ST-segment Elevation Myocardial Infarction), per cui veniva eseguita una coronarografia urgente, durante la quale venivano somministrati per via intra arteriosa 125 mL di IOCM (Iodixanolo 320 mg/mL). Veniva documentata trombosi a carico di un pregresso stent sulla coronaria interventricolare anteriore, che veniva efficacemente trattata tramite una Percutaneous Transluminal Angioplasty (PTA) e il posizionamento di uno stent medicato (drug-eluting stent, DES), pertanto veniva avviata duplice terapia antiaggregante. Alcune ore dopo la procedura, il paziente manifestava un episodio di afasia per cui veniva eseguita una angio-TC (Tomografia Computerizzata) cerebrale che escludeva eventi ischemico-emorragici acuti, ma evidenziava una lesione occipitale subacuta e una stenosi critica della carotide interna sinistra, con indicazione a correzione per via percutanea.

Nelle giornate successive il paziente mostrava una graduale e spontanea regressione della sintomatologia, pertanto si procedeva all’esecuzione in elezione di PTA della nota stenosi carotidea. Al fine di ridurre il rischio di nefropatia da mezzo di contrasto (PC-AKI, Post Contrast-Acute Kidney Injury) in paziente con diuresi conservata, nelle 12 ore precedenti l’esame, veniva somministrata soluzione fisiologica 0,9% 1000 mL, anche in considerazione dei valori di pressione arteriosa sistemica ai limiti inferiori (Pressione Arteriosa media, PAm 100/65 mmHg) a seguito dell’evento cardiologico. Al fine, inoltre, di favorire l’eliminazione urinaria di IOCM è stata confermata la terapia diuretica cronica. L’accesso arterioso avveniva tramite l’arteria femorale destra, venivano somministrati di 75 mL di IOCM (Iopidamolo 300 mg/ml) intra arterioso. Veniva posizionato uno stent 10×40 mm a livello del bulbo carotideo poi dilatato con un palloncino 5×20 mm, escludendo così la nota placca ateromasica. L’intervento avveniva in assenza complicanze intra procedurali e si otteneva la completa ricanalizzazione della arteria carotidea.

Dopo due ore dalla procedura il paziente appariva confuso, non collaborante, e disartrico. I nervi cranici esplorati erano intatti, ad eccezione di un deficit aspecifico del VII nervo e del nervo oculomotore in paziente affetto da completa perdita del visus. Nelle ore successive il paziente sviluppava inoltre iperpiressia (TC fino a 38,5 °C), in assenza di segni clinici o laboratoristici suggestivi per infezione in atto (le emocolture e le colture del liquido peritoneale sono risultate negative).  Non vi erano segni clinici di sovraccarico idrico e la diuresi era conservata. I parametri vitali documentavano un quadro di ipotensione (PAm 90/50 mmHg). In Tabella 1 sono riportati i principali parametri biochimici del paziente che si riferiscono a un mese precedente al ricovero in fase di stazionarietà clinica e immediatamente precedenti all’evento acuto (Tabella 1).

  Un mese prima del ricovero in fase di stazionarietà clinica Il giorno precedente l’evento acuto
BMI (kg/m2) 29,4
Pressione arteriosa (mmHg) 160/70 100/65
Diuresi/24 ore (mL) 1100 700
Creatinina (mg/dL) 6,0 4,58
eGFR (mL/min/1,73 m2) 8 11
Urea (mg/dL) 84 65
Na (mmol/L) 137 138
K (mmol/L) 3,6 3,5
Calcio (mg/dL) 8,5 9,0
HCO3(mmol/L) 26,8 28,0
Emoglobina (g/L) 108 138
Albumina (g/dL) 3,9 3,5
BNP (ng/L) 13459 9000
Schema dialitico Agente osmotico, Volume Agente osmotico, Volume
CCPD1 NIPD Glucosio 1,36%, 9.5 L
Scambio diurno Icodestrina 7,5%, 1,5 L
CAPD Scambi diurni Glucosio 1,36%, 2 L x 2
Scambio notturno Icodestrina 7,5%, 2 L
UF nelle 24 ore (ml) 900 mL 1100 mL
Total wKt/Vurea 2,1
Total wCCr (ml/min/1,73m2) 60
Tabella 1. Parametri bioumorali del paziente un mese prima del ricovero in fase di stazionarietà clinica e il giorno precedente l’evento acuto.
BMI: Body Mass Index; eGFR: estimated Glomerular Filtration Rate; UF: Ultrafiltrazione; CCPD1: Continuous Cycling Peritoneal Dialysis; NIPD: Nocturnal Intermittent Peritoneal Dialysis; CAPD: Continuous Ambulatory Peritoneal Dialysis; Total wKt/Vurea: Total (renale e peritoneale) weekly Kt/Vurea; Total wCCr: Total (renale e peritoneale) weekly Clearance della Creatinina; BNP: Brain Natriuretic Peptide.

La TC e la Risonanza Magnetica Nucleare (RMN) encefaliche escludevano fatti ischemici o emorragici acuti, ma la TC evidenziava segni di edema cerebrale diffuso (Figura 1). L’Elettro Encefalo Gramma (EEG) mostrava segni di anomalie dell’emisfero destro correlabili a sequele di recente ischemia. Veniva quindi impostata idratazione con soluzione fisiologica 0,9% (1000 mL nelle 24 h) e somministrati Mannitolo 18% (100 mg bis in die) e Desametasone (8 mg bis in die) a scopo anti-edemigeno. Il paziente proseguiva il trattamento di CAPD implementato con uno scambio supplementare al giorno (agente osmotico: glucosio 2,27% 2 L) a scopo depurativo. Nei due giorni successivi si documentava una remissione completa della sintomatologia. La clinica, il timing di insorgenza e di regressione, le indagini laboratoristiche e strumentali consentivano pertanto di ipotizzare una encefalopatia secondaria all’utilizzo di IOCM in paziente con numerosi fattori di rischio per tale complicanza.

Figura 1. TC senza mezzo di contrasto: edema cerebrale diffuso.
Figura 1. TC senza mezzo di contrasto: edema cerebrale diffuso.

 

Discussione

Nel presente lavoro abbiamo descritto un raro caso di comparsa di sintomatologia neurologica scatenata dalla somministrazione intra-arteriosa di IOCM in un paziente con più comorbidità (diabete mellito, ESRD, ipertensione arteriosa, scompenso cardiaco, pregressi TIA) [2, 8].

È noto che la somministrazione di mezzo di contrasto si associa al rischio di sviluppare MARCE, che comprendono sia forme di nefropatia da mezzo di contrasto (PC-AKI) che altre complicanze sistemiche come eventi cardiaci e cerebrali [1, 2]. Se per la PC-AKI vi sono numerose evidenze [9], limitatamente a quanto a noi noto, vi è poca letteratura in merito alle altre forme di MARCE e in particolare alla CIE.

La fisiopatologia della neurotossicità da mezzo di contrasto non è completamente conosciuta: l’ipotesi è che il mezzo, attraversando la barriera ematoencefalica, si accumuli ed eserciti una tossicità diretta nei confronti delle cellule nervose e l’iperosmolarità dello stesso contribuirebbe all’instaurarsi dell’edema cerebrale [10, 11].

Clinicamente, la CIE è una diagnosi di esclusione di altre patologie cerebrali acute e pertanto l’imaging cerebrale è utile per la diagnostica differenziale; l’uso di TC e di RMN consente di escludere eventi embolici, emorragici ed emodinamici. Alla RMN è possibile riscontrare aree corticali edematose che appaiono iper-intense, alla CT è possibile osservare aree di iperattenuazione corticale che simulano lesioni ischemiche subcorticali e lesioni emorragiche; tuttavia la TC potrebbe anche non mostrare alcun reperto patologico [5, 12]. L’imaging del nostro paziente escludeva fatti ischemico-emorragici acuti, mentre la presenza di edema cerebrale diffuso era compatibile con il sospetto clinico di CIE. Una presentazione clinica analoga si potrebbe riscontrare in corso di Posterior Reversible Encephalophaty Syndrome (PRES), quadro neurologico spesso secondario a quadri ipertensivi, indotto da farmaci, preeclampsia e CKD. Questa condizione si associa tipicamente a ipodensità patologiche nelle aree cerebrali posteriori alla TC, e zone di edema vasogenico localizzato, con ipodensità nelle sequenze T1-pesate e iperdensità nelle sequenze T2-pesate alla RMN , che nel nostro paziente non era possibile documentare.

Per quanto riguarda la terapia della PC-AKI, secondo le recenti line guida ESUR (European Society of Urology and Radiology) [14], l’identificazione dei pazienti ad alto rischio, la prevenzione e lo stretto monitoraggio dopo la somministrazione rappresentano le azioni più efficaci per ridurne l’incidenza.

Gli IOCM vengono eliminati rapidamente attraverso il glomerulo; in caso di rallentata eliminazione essi diffondono nel compartimento extravascolare fino all’equilibrio. Pertanto una ridotta funzionalità renale determina una riduzione della clearance e un accumulo di IOCM nei tessuti. Nei pazienti normofunzione renale (eGFR>100 mL/min) il 50% di IOCM è escreto nelle urine dopo circa 2 ore; nei pazienti con danno renale severo (eGFR<25 mL/min) l’eliminazione urinaria del 50% di IOCM si ottiene in 16-84h; mentre nei pazienti con ESRD l’eliminazione è molto più lenta, con un contributo da parte dell’eliminazione biliare [15].

L’emodialisi (Haemodialysis, HD) e la PD risultano efficaci nel rimuovere dal corpo gli agenti di contrasto, anche se la PD in tempi più lunghi rispetto all’HD. In particolare, la CAPD rimuove tra il 36% e l’80% del IOCM somministrato in sette giorni [16]. Nella Tabella II abbiamo riportato le principali evidenze in letteratura in merito all’eliminazione del mezzo di contrasto in relazione alla funzione renale e alle diverse tecniche dialitiche.

  Mezzo (V) Osmolarità (mOsm/kg H2O) Tecnica dialitica Emivita (media) Tasso di rimozione (tempo) Modalità di escrezione Bibliografia
eGFR>100 mL/min Iomeprolo

(50 mL)

730 2h 87% (12h)

90% (24h)

Urine (93%)

Feci (1,5%)

Lorusso, 2001

[15]
eGFR 75-50 mL/min 4-8h Urine (90%)

Feci(2,4%)

eGFR 26-50 mL/min 4-8h Urine (82%)

Feci (2,6%)

eGFR<25 mL/min 16-84h Urine (68%)

Feci (7%)

Bile

HD HD LF 83% (4h) Dialisato (58%)
  Iopromide/

Iomeprol

(64 mL)

777/791 HD LF 1h55’ 64% (4h) Schindler, 2001

[26]
  HD HF 1h40’ 74% (4h)
  Iopromide

Iomeprol (60 mL)

HDF online 1h35’ 82% (4h)
  HF online 2h10’ 62% (4h)
PD Iopamidolo

(30 mL)

796 CAPD (2×3.86%+

1,36%)

38h

 

36-80% (7 giorni) Urine (27%) Donnelly, 1992

[27]
  APD

(36-60l)

16-18h 43-72%  
Tabella 2. Caratteristiche di eliminazione dei mezzi di contrasto in base all’eGFR o alla tecnica renale sostitutiva.
eGFR: estimated Glomerular Filtration Rate; HD: Haemodialysis; PD: Peritoneal Dialysis; LF: Low Flux; HF: High Flux; CAPD: Continuous Ambulatory Peritoneal Dialysis; APD: Automated Peritoneal Dialysis.

Tuttavia non vi sono evidenze che indichino un vantaggio nell’eseguire una seduta dialitica post esposizione all’IOCM per prevenire la PC-AKI anche nei pazienti a rischio [16].

Pertanto per la prevenzione della nefropatia da mezzo di contrasto, la principale strategia è rappresentata dall’idratazione pre- e post-esposizione a mezzo di contrasto con Na bicarbonato 1,4% 3 mL/kg/h nell’ora precedente e con soluzione fisiologica al 0,9% 1 mL/kg/h per 3-4 ore prima e 4-6 ore dopo, compatibilmente con la funzione renale e cardiaca [5, 12, 17]. Anche i farmaci anti-infiammatori non steroidei (FANS) potrebbero causare una maggior esposizione al mezzo di contrasto per riduzione del flusso ematico renale [18]. Il nostro paziente era in duplice terapia antiaggregante con ticagrelor, inibitore del recettore P2Y12 dell’ADP, che non presenta attività anti-infiammatoria, e con acido acetilsalicilico a bassa dose (100 mg al giorno). A tale dosaggio tale molecola esercita un’azione prevalentemente antiaggregante rispetto a quella anti-infiammatoria [19], con un impatto trascurabile sulla funzionalità renale [20].

Viceversa, per le forme di CIE non vi sono chiare evidenze in letteratura in merito a un trattamento ottimale [21]. La somministrazione di fluidi, al fine di favorirne l’eliminazione renale, sembra essere utile nei pazienti con funzione renale residua; il ricorso a farmaci sintomatici (anticonvulsivanti, anti piretici) è indicato. La somministrazione di steroidi a scopo anti-edemigeno può essere considerata in caso di documentato edema cerebrale [22]; analogamente, il mannitolo, in quanto agente iperosmolare, viene utilizzato per ridurre l’edema cerebrale, richiamando acqua libera in eccesso a livello della barriera ematoencefalica e favorendone l’eliminazione a livello renale; il suo uso nei pazienti con ESRD è dibattuto dal momento che il rallentato metabolismo del IOCM in pazienti oligoanurici potrebbe associarsi a una retrodiffusione dello stesso. Il nostro paziente aveva una diuresi conservata e il mannitolo potrebbe aver contribuito alla sua eliminazione [7, 24].

Limitatamente a quanto per noi noto, non sono riportati in letteratura casi di pazienti in PD che abbiano sviluppato CIE. Sono stati decritti invece pochi casi di CIE in pazienti affetti da CKD e in pazienti con ESRD in HD cronica [21, 23, 25], e alcuni casi di sindromi neurologiche (Posterior Reversible Encephalopathy Syndrome, PRES) in pazienti con CKD [13].

Per i primi è stata somministrata terapia medica, mentre quelli in HD cronica hanno eseguito anche una seduta emodialitica supplementare, che potrebbe aver favorito la rimozione più rapida di mezzo di contrasto [11, 16].

Il nostro paziente, in PD cronica con ancora funzione renale residua, ha raggiunto in pochi giorni una completa risoluzione della sintomatologia, giovandosi di idratazione, somministrazione di mannitolo e steroidi ed implementazione degli scambi di dialisi peritoneale già in corso. Non abbiamo sottoposto il paziente a un trattamento di dialisi peritoneale automatizzata, che rimuoverebbe in maggior percentuale il mezzo di contrasto utilizzando tuttavia alti volumi (36-60 L) in un periodo di tempo lungo (16-18 ore), né ad un trattamento di emodialisi per evitare una conseguente disidratazione e un peggioramento dell’ipotensione [16]. La terapia medica oltre che funzione antiedemigena può aver favorito l’eliminazione renale del IOCM, a cui si è aggiunta la clearance peritoneale che può aver contribuito sia a una miglior depurazione che a una parziale eliminazione del mezzo di contrasto.

 

Conclusioni

La CIE è una complicanza rara, la cui patogenesi al momento non risulta completamente chiara, ma che va ricordata nella diagnosi differenziale nei pazienti con alterazione della funzione renale che sviluppino sintomi neurologici dopo essere stati sottoposti a procedure con mezzo di contrasto intra arterioso, in considerazione della rallentata eliminazione del mezzo di contrasto, e con altri fattori di rischio associati.

 

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Peritoneal Dialysis in Italy: the 8th GPDP-SIN census 2022

Abstract

Objectives. The results are reported here of the 8th National Census (Cs-22) of Peritoneal Dialysis in Italy, carried out in 2022-23 by the Italian Society of Nephrology’s Peritoneal Dialysis Project Group and relating to 2022.
Methods. The Census was conducted in the 227 non pediatric centers which performed Peritoneal Dialysis (PD) in 2022. The results have been compared with the previous Censuses carried out since 2005.
Results. Incidence: in 2022, 1350 patients (CAPD=52.1%) started on PD (1st treatment for ESRD). PD was started incrementally by 35.3% in 136 Centers. The catheter was placed exclusively by a Nephrologist in 17.0% of known cases. Prevalence: there were 4152 (CAPD=43.4%) patients on PD on 31/12/2022, with 21.1% of prevalent patients on assisted PD (family member caregiver: 86.3%). Out: in 2022 the PD drop-out rate (ep/100 pt-yrs) was: 11.7 to HD; 10.1 death, down; 7.5 Tx. The main cause of transfer to HD remains peritonitis (23.5%), although its reduction over the years is confirmed (Cs-05: 37.9%). Peritonitis/EPS: the incidence of peritonitis in 2022 was 0.176 ep/pt-yr (696 episodes). The incidence of new cases of EPS fell in 2021-22 (7 cases). Other results: the number of Centers using 3.86% for the peritoneal equilibration test (PET) (57.7%) increased. PD for heart failure continues to be used in 44 Centers (66 pts).
Conclusions. Cs-22 confirms PD’s good results in Italy.

Keywords: Peritoneal Dialysis, technique failure, incremental Peritoneal Dialysis, peritonitis, peritoneal equilibration test (PET)

Background

The Peritoneal Dialysis Project Group (GPDP) of the Italian Society of Nephrology (SIN) investigates the state of Peritoneal Dialysis (PD) in Italy periodically by means of a Census carried out in the Centers which use it [16]. In the last edition, relating to 2019 [6], the situation was shown to be substantially stable, although the survey was conducted at the height of the CoViD pandemic and for the first time was incomplete.

All the Centers using PD took part again in the current edition, which was the Eighth and relates to 2022. It should be remembered, however, that these Centers represent around two-thirds of public Centers (PD is not available as a service in the remainder). When it is considered also that PD is not used in private Centers, the method is actually provided in a minority of Italian Dialysis Centers, and used by less than 10% of patients on Dialysis. The reasons for such a disheartening picture were investigated in the very first Census carried out by SIN in 2004 [7] and are likely to still be the same, all the more so if the constant improvement in the results achieved by PD over the years is considered.

The current edition features various grounds for interest and new aspects. First of all, it is the first “post-CoViD” edition. The number of Centers taking part using the new data collection system [6] increased significantly, allowing for greater precision in the data collected. For the first time the Census thoroughly investigated not only the incidence, but also the etiology of peritonitis, and certain structural aspects of PD Centers, such as the dedicated personnel and the training which will be examined in future.

This report presents the results of the 8th edition, conducted in 2022-2023 and relating to 2022, compared with those of the previous years.

Completing the report is the examination by leading experts on the subjects of certain aspects of PD, including the incremental prescription, peritoneal sclerosis and an assessment of peritoneal permeability.

 

Materials and methods

The GPDP Census collects aggregate data relating to PD, and is targeted at all the non-pediatric Centers which have used PD in the year in question.

Data collection. As for 2019 [6], in the current edition the aggregate data were collected in two different ways. The first was analytical, using specially designed software: a sort of medical record in which individual patients are entered systematically and the data are exported for the Census in aggregate form. For the protection of privacy, the program was developed without a cloud component, so all the data collected are stored locally and the possibility of backup to server is delegated to the operator. The number of Centers using this system increased from 110 in 2019 to 175 in 2022. The method used by the remaining 52 Centers was the traditional collection of data by filling in the online questionnaire used for previous editions.

In total, the Census reports data from 227 Centers, which is 100% of Italian PD Centers. Of the 8 editions so far, only the Census relating to 2019 was incomplete (198 Centers).

Participating Centers. The initial list of public Centers using PD established in the first SIN Census conducted for 2004 [7] has been updated over the years through attendances at Congresses, Conferences and subsequent SIN Censuses.

The number of Centers taking part for 2022 was 229, 2 of which were excluded as they did not treat any patients during 2022 (having ceased PD activity). While all the Centers responded to the questions on the incidence and prevalence of PD, 50 Centers provided no data on the incidence and prevalence of HD (Figure 1).

Information. The structure of the Census provides for a series of repeated pieces of information – unchanged since the first edition in 2005 [1] – relating to incidence, prevalence, method change or interruption, assisted PD, peritonitis, and non-renal PD. Encapsulating peritoneal sclerosis (EPS) has been added since 2008, and home visits and the peritoneal equilibration test (PET) since 2010 [2]. The questions on catheters resumed in the 2016 edition [5]. Furthermore, with the analytical data collection method information has become available for the first time on the causes of Renal Insufficiency, causes of death, certain organizational aspects such as training methods and available resources, and the etiology of peritonitis.

Data verification and comparison. The data collected initially were subjected to an initial congruence analysis. Any inconsistent data were corrected wherever possible by follow-up phone call, or were considered missing or incomplete, as appropriate. Any corrections and the number of Centers involved are reported in detail in the presentation of the single results.

Definitions and calculations. All the patients who started as first treatment on PD and HD from 01/01/2022 to 31/12/2022 were considered incident. Of these, the patients on ≤2 exchanges/day or ≤4 sessions/week with CAPD (Incr-CAPD) and APD (Incr-APD) respectively were considered as on incremental PD (Incr-PD). Prevalence referred to patients on dialysis at December 31st. For these, a need for assistance referred to the involvement of a caregiver in the performance of the dialysis procedures. Patients on PD due to non-renal causes (GFR ≥15 ml/min/1.73m2) were considered separately: the Census data always refer to patients who started PD due to ESRD.

The calculation of the follow-up to which events are related represents the critical aspect of the Census. With it being impossible to calculate the actual data (the sum of the periods all patients spent on PD in 2022) the follow-up has always been estimated by taking the mean of prevalent patients at the beginning and the end of the year, a method which has also recently been validated [8]. The prevalent patients at the beginning of the year were calculated by taking the prevalent patients at the end of the year, adding drop-outs for all causes, and subtracting new patients to PD (information available). This year it was possible to calculate the follow-up precisely for the 175 Centers which used the “2.2” program. In these Centers the comparison between the two methods showed that “traditional” follow-up underestimates the “actual” follow-up by 5.4%, so it overestimates by an equivalent amount the incidence of the events considered. As the data collection system was still mixed for 2022, the traditional method was used to calculate follow-up for all 227 Centers in order to be able to compare current results with previous years.

The drop-outs from PD recorded in the year were related to 100 patient-years of follow-up, while for peritonitis the incidence was calculated as episodes/patient-years (ep/pt-year). Episodes of EPS refer to the entire 2021-22 two-year period in the case of traditional collection, and the 2020-22 three-year period for the analytical method.

Statistical analysis was limited to looking for any differences with the Chi-square test.

Figure 1: Centers which used PD in 2022 for at least 1 patient.
Figure 1: centers which used PD in 2022 for at least 1 patient. They all sent the data relating to PD; 50 of these did not send the incidence and prevalence data relating to HD. The system used for sending the data is shown in the graphic: 52 by means of the traditional system, which provides for the entry of aggregate data; 175 using the dedicated program in which each patient is entered separately, and the program calculates and sends the aggregate data.

 

Results

Incidence and initial method

In 2022 PD was started on as first treatment by 1350 patients, 703 of whom using CAPD and 647 APD. The Centers with no incidence in PD in 2022 numbered 11.

As regards HD, 177 Centers provided incidence and prevalence data. In these 177 Centers, 1066 patients started on PD as first treatment, and 4329 on HD, giving a percentage incidence of PD of 19.8% (Table I) (Figure 2). So in relation to the 177 Centers which also sent data on HD, a fall in both the number of patients treated overall with PD in Italy (-15.4% compared to 2016) and the percentage incidence of PD was recorded for 2022. The most widely-used initial PD method remains CAPD (52.1%).

Table I: incident patients and initial PD method in the non-pediatric Centers which used PD in 2022 compared with previous years. The number of Centers not sending HD incidence data has constantly increased since 2016.
Table I: incident patients and initial PD method in the non-pediatric Centers which used PD in 2022 compared with previous years. The number of Centers not sending HD incidence data has constantly increased since 2016.
Figure 2: Number of new patients on 1st treatment (incident) in the years surveyed.
Figure 2: number of new patients on 1st treatment (incident) in the years surveyed. The percentage incidence is calculated on the total number of incident patients (PD + HD). Since 2016 a number of Centers have not sent HD incidence data, so the PD percentage is only calculated for the Centers which have sent the data (light yellow, value in italics). The total number of incident patients is given at the top of each column. It is to be remembered that the 2019 data are incomplete.

For the first time, basic nephropathy data are available, though only for the Centers which sent data using the 2.2 system. The conditions in which PD is most used are Nephroangiosclerosis (24.4%) and chronic Glomerulonephritis (22.3%). Diabetic nephropathy is the cause of ESRD in 15.4% of cases, while in 15.3% it is not known (Figure 3).

Figure 3: Type of nephropathy in incident patients on PD.
Figure 3: type of nephropathy in incident patients on PD. This was not requested by the traditional system for sending the data, so the breakdown shown in the Figure refers to 1004 patients in 174 Centers (1 Center was excluded for data incongruence).

Placement of the peritoneal catheter

All insertions were considered for the placement of the catheter. Excluding 96 patients due to incongruent data (which will be verified in a subsequent analysis), in the 1480 patients who started on PD in 2022, there was a further increase in placements by a surgeon alone, the number of placements by a surgeon and a nephrologist together was stable, and placements by a nephrologist alone diminished (Figure 4).

Figure 4: Operators involved in the placement of the peritoneal catheter.
Figure 4: operators involved in the placement of the peritoneal catheter. The percentage has also been calculated excluding the catheters for which the response was “other” or not specified. The 2016 data are given in the box (excluding “other” and not specified).

Initial dialysis dose – incremental peritoneal dialysis

PD was started with the incremental method (Incr-PD) by 477 patients in 2022, equaling 35.3% of total incident patients (Figure 5); it was used for at least 1 patient by 136 Centers, equaling 59.9% of the 227 Centers (63.0% when excluding the 11 Centers with no incidence).

For the patients who started PD with an incremental dose, the most widely-used method, as in previous years, was CAPD (82.8%), as opposed to the patients who started with a full-dose prescription, for whom APD is significantly more widely-used (64.7% – p<0.0001) (Figure 5). CAPD is a PD method that is increasingly associated with the incremental prescription and the Centers that perform it.

Over the years the number and percentage of incident patients on Incr-PD have been constantly rising, from the 11.9% of 2005 to the current 35.3% (Figure 6). The number of Centers prescribing it, which increased until 2016, remained the same in 2022 in terms of percentage (62.9% in 2016; 63.0% in 2022 of the Centers which started new patients on PD) (Figure 7). The increase recorded in 2022 can therefore be attributed to an increased use in the Centers which already used it, where it was prescribed for 47.8% of patients.

The Centers using Incr-PD are “larger” than the Centers which do not prescribe it, in terms of both incident (7.3 pt/year vs 4.4 pt/year) and prevalent patients (21.3 patients vs 15.0 patients) (Figure 8).

Excluding the Centers with zero incidence and those which did not send HD data, the use of incremental PD is associated, as in previous years, with greater use of PD in general (22.4% in 114 Centers vs 14.4% in 56 Centers – p<0.005) (Figure 9).

Figure 5: Incremental dialysis in 2022. The method of PD used (CAPD and APD) is given in the lateral columns for “incremental” (on the left) and “full dose” patients (right).
Figure 5: incremental dialysis in 2022. The method of PD used (CAPD and APD) is given in the lateral columns for “incremental” (on the left) and “full dose” patients (right).
Figure 6: Percentage of total incident patients who started PD with an incremental prescription (2 or fewer exchanges on CAPD and 4 or fewer sessions on APD).
Figure 6: percentage of total incident patients who started PD with an incremental prescription (2 or fewer exchanges on CAPD and 4 or fewer sessions on APD).
Figure 7: Percentage of Centers which used the incremental prescription for at least one patient.
Figure 7: percentage of Centers which used the incremental prescription for at least one patient. The percentage was calculated excluding the Centers which did not start any incident patients. If it is related to the total number of Centers the value is slightly lower, but the trend over time does not change.
Figure 8: A) Percentage of Centers over time divided into those which recorded no new patients (INCID = 0)
Figure 8: A) percentage of Centers over time divided into those which recorded no new patients (INCID = 0), those which recorded new patients but did not prescribe the incremental mode (INCR = 0), and those which used it for at least 1 patient (INCR>0). B) Size of the 3 types of Centers, in terms of both incident (above) and prevalent patients (below) in relation to 2022.
Figure 9: A) The percentage use of PD for incident patients in the Centers which do or do not use the incremental prescription.
Figure 9: A) the percentage use of PD for incident patients in the Centers which do or do not use the incremental prescription. The data relates to the 177 Centers which also provided HD data. Of these, 7 were excluded for Incidence = 0. Of the remaining 170, Incr-PD was prescribed in 114 Centers (INCREM.SI). B) The PD admission Odds Ratio in INCREM.SI with respect to INCREM.NO Centers over the years.

Patients from other treatments

In 2022, 178 patients transferred from HD to PD (Figure 10) (Table II).

1st TREAT. FROM HD FROM TX NEW TO PD FROM HD (%) FROM Tx (%)
2005 1443 89 25 1557 5,7 1,6
2008 1379 82 32 1493 5,5 2,1
2010 1429 126 36 1591 7,9 2,3
2012 1433 113 50 1596 7,1 3,1
2014 1652 161 46 1859 8,7 2,5
2016 1595 119 50 1764 6,7 2,8
2019 1363 125 44 1532 8,2 2,9
2022 1350 178 48 1576 11,3 3,0
Table II: patients (absolute value and percentage of all new patients to PD) from HD and return post-Transplant.
Figure 10: New patients to PD, sum of incident patients, transfers from HD and returns post-Tx.
Figure 10: new patients to PD, sum of incident patients, transfers from HD and returns post-Tx.

As expected, this data is decidedly lower than the number of patients switching from PD to HD (464 drop-outs in 2022), but higher in both absolute and percentage terms: indeed, in 2022 it represents 11.3% of all new patients to PD compared to 5.7% in 2005 (Figure 11). If for every 100 patients who transferred from PD to HD in 2005 17 took the reverse path, in 2022 the latter figure was 37. As regards a return to PD post-Transplant, the numbers and percentages have remained substantially unchanged over time (Figure 12).

Figure 11: Trend over time in the percentage of patients who started on PD from HD and Tx out of the total number of new patients on PD.
Figure 11: trend over time in the percentage of patients who started on PD from HD and Tx out of the total number of new patients on PD.
Figure 12: Percentages of patients returning post-Transplant on HD (red) and on PD. Only Centers with complete data for HD as well are considered.
Figure 12: percentages of patients returning post-Transplant on HD (red) and on PD. Only Centers with complete data for HD as well are considered.

Change of PD method

Information on the change of method were available for 224 Centers. In these Centers, 165 patients transferred from CAPD to APD in 2022, while 43 transferred from APD to CAPD (Figure 13). As in previous years, the reason for the change in around half of cases was patient and/or caregiver choice. Other grounds were insufficient clearance / UF for the switch from CAPD to APD, and catheter malfunction for the switch from APD to CAPD.

Figure 13: Change of PD method in 2022. Three Centers did not provide the data.
Figure 13: change of PD method in 2022. Three Centers did not provide the data.

Prevalence and PD method

At December 31st 2022 there were 4152 patients on PD, with 1803 on CAPD and 2349 on APD. Therefore, compared with 2016, a reduction of 9.9% was recorded in the prevalent population (Figure 14) (Table III). In the 177 Centers with complete incidence and prevalence data for HD as well, there were 3191 patients on PD and 18,259 on HD, with a 14.9% PD prevalence.

The most widely-used PD method among prevalent patients is APD (56.6%) (Figure 15), with a further increase compared to previous years (Table III).

The turnover calculated as the ratio of prevalent patients to the total of new patients on PD in 2022 was 31.6 months, substantially unchanged compared to previous years (it was 32.9 months in 2008). The trend in turnover over the years is given in detail in Figure 16.

Table III: Prevalent patients at 31/12/2022 and PD method in the non-pediatric Centers
Table III: prevalent patients at 31/12/2022 and PD method in the non-pediatric Centers which used PD in 2022 compared with previous years. The number of Centers not sending HD incidence data has increased constantly since 2016. * the values of the First SIN Census carried out in 2004 are given since data relating to HD were not requested in the first GPDP Census in 2005.
Figure 14: Number of patients treated with PD at December 31st of each year (prevalent) in the years surveyed.
Figure 14: number of patients treated with PD at December 31st of each year (prevalent) in the years surveyed. The percentage prevalence was calculated on total prevalent patients (PD + HD). Since 2016 a number of Centers have not sent HD prevalence data, so the PD percentage is only calculated for the Centers which have sent the data (light blue, value in italics). The total number of prevalent patients is given at the top of each column. It is to be remembered that the 2019 data are incomplete. In 2005 the HD prevalence data were not requested, so those of the 2004 SIN Census are considered.
Figure 15: Breakdown of incident and prevalent patients between CAPD and APD.
Figure 15: breakdown of incident and prevalent patients between CAPD and APD.
Figure 16: Duration of PD calculated by multiplying the NEW/PREVALENCE ratio by 12.
Figure 16: duration of PD calculated by multiplying the NEW/PREVALENCE ratio by 12. This is obviously valid in steady state conditions, while for 2022 this may not be the case, although the lower incidence was partly offset by the rise in patients from HD.

Assisted PD

In Cs-22 the number of prevalent patients requiring a caregiver (assisted PD) was 878 (21.15% of all prevalent patients on PD) (Figure 17). Compared to 2019 (976 patients on Assisted PD in an incomplete Census), this is a significant reduction (p<0.005).

The caregiver is a family member in 86.3% of cases, a live-in carer in 7.4%, a home nurse in 1.7%; finally, 4.6% (40 patients) perform PD in facilities for the elderly. A reduction was recorded for 2022 in the number of live-in carers, with an increased involvement of family members. The number of patients treated with PD in residential care homes was unchanged (Figure 18).

Figure 17: Assisted PD in the prevalent patients on 31/12/2022 and type of caregiver involved.
Figure 17: assisted PD in the prevalent patients on 31/12/2022 and type of caregiver involved. Given inside the graphic for the latter are the percentages referred to the total of prevalent patients, and near every single component the percentages in relation to the total number of patients on assisted PD.
Figure 18: Trend over time in caregivers involved in assisted PD.
Figure 18: trend over time in caregivers involved in assisted PD.

Change of method and drop-out

Figure 19 shows overall drop-out and drop-out due to transfer to HD, death, and transplant, expressed as both number of patients and events/100 pt-years.

The number of deaths recorded in 2022 was 400 (10.1 ep/100 pt-years), 464 patients transferred to HD (11.7 ep/100 pt-years) and 296 to transplants (7.5 ep/100 pt-years). A reduction in mortality was confirmed for 2022 compared to 2016.

Other causes of drop-out from PD in 2022 were voluntary refusal to continue dialysis (burn out) for 21 patients, Recovery of Residual Renal Function (RFRR) in 14 patients and on “other” grounds for 6 patients. Burn out was proposed for the first time in 2022, and may have been attributed in the past to death or “other” grounds.

With regard to drop-out to HD (Figure 20), the single main cause remains peritonitis (23.5%), but its reduction over the course of the years was confirmed (2005: 37.9%; 2008: 36.7%; 2010: 30.4%; 2012: 28.2%; 2014: 24.8%; 2016: 23.8%). The second cause – significantly on the increase – is the impossibility to continue on PD (22.4%). Traditionally this refers to events that render the patient no longer suitable for the performance of the dialysis procedures due to the onset of barriers to independence (physical, psychological, cognitive) in the event of absence or loss – if already on Assisted PD – of the caregiver. Other clinical events may also be attributed to this cause however. Finally, catheter is increasing as cause of drop-out (14.0%).

The main cause of death is heart disease (42.3%), while peritonitis represents 1.9% of deaths (Figure 21).

Figure 19: Causes of drop-out from PD over the years. In 2019 the Census was incomplete.
Figure 19: causes of drop-out from PD over the years. In 2019 the Census was incomplete.
Figure 20: Causes of transfer to HD over the years. In 2019 the Census was incomplete.
Figure 20: causes of transfer to HD over the years. In 2019 the Census was incomplete.
Figure 21: Causes of death in the Centers that used the dedicated 2.2. program to send the data.
Figure 21: causes of death in the Centers that used the dedicated 2.2. program to send the data.

Peritonitis

The number of episodes of peritonitis recorded in 2022 was 696 in 226 Centers, which for a total follow-up of 3943.5 years (47.322 months) is equivalent to 0.176 episodes per patient-year, or in other terms 1 episode every 68.0 patient-months, a lower incidence than recorded in previous years. As far as the percentage of negative cultures is concerned (134 episodes, equaling 19.3% of the total), the data is not significantly different to previous years (Table IV).

The peritonitis trend is given in both Table IV and Figure 22.

The etiology was analyzed for 627 cases of peritonitis reported in 211 Centers. One Center did not report the data, and 15 reported a higher number defined by the etiological agents than the cases of peritonitis reported overall (+18). However, as 8 Centers reported a lower number of etiological agents for peritonitis than the total declared (-17), the net difference was only 1 episode, confirming the validity of the overall data.

Half (50.1%) were caused by Gram positives, 27.9% by Gram negatives and 2.7% by unspecified germs (Figure 23). Cases of culture-negative peritonitis in these Centers were lower (17.9%) than those declared overall by all the Centers (134 episodes, 19.3%). Figure 24 details the different isolated microorganisms.

Of the episodes of peritonitis recorded in 2022, 323 (46.4%) occurred during CAPD and 373 (53.6%) APD, reflecting the breakdown of the 2 methods in prevalent patients.

Table IV: The episodes of peritonitis recorded by 73% of surveyed Centers are given for 2005, while not all recorded them in 2019 (and 4 did not report the data).
Table IV: the episodes of peritonitis recorded by 73% of surveyed Centers are given for 2005, while not all recorded them in 2019 (and 4 did not report the data). For 2022 the data refer to all the Centers, except 1 which was unable to retrieve the data. The calculation is taken from the overall number. Any discrepancy with the number of etiological agents has not been taken into account for standardization with the previous years (in which the etiology was not investigated).
Figure 22: Incidence of peritonitis in 2022. The peritonitis reported for 2005 was recorded by 73% of the Centers surveyed, while not all were surveyed in 2019
Figure 22: incidence of peritonitis in 2022. The peritonitis reported for 2005 was recorded by 73% of the Centers surveyed, while not all were surveyed in 2019 (and 4 did not report the data). For 2022 the data refer to all the Centers, except 1 due to impossibility to retrieve the data. The count is taken from the total number. Any discrepancy with the number of etiological agents was not taken into account for standardization with the previous years (in which the etiology was not investigated).
Figure 23: Etiology of peritonitis – breakdown based on the main categories.
Figure 23: etiology of peritonitis – breakdown based on the main categories.
Figure 24: Etiology of peritonitis in detail.
Figure 24: etiology of peritonitis in detail.

Encapsulating peritoneal sclerosis (EPS)

Of the 7 new episodes of EPS reported during the period 2020-22, 5 were diagnosed in the course of PD and 2 following transfer to HD. No cases were reported following a transplant (Figure 25).

A separate paper in this number is dedicated to discussing this finding, which is similar to 2019, but in constant decline.

Figure 25: Sclerosing peritonitis over time. For 2022 only the number of extracted cases is reported.
Figure 25: sclerosing peritonitis over time. For 2022 only the number of extracted cases is reported.

PET

Peritoneal permeability is assessed by most of the Centers (88.1%). although the number of Centers which do not consider it has grown further (2.2% in 2010 vs 11.9% in 2022).

For some time now the most widely-used method is 3.86%-PET rather than Twardowski’s 2.27%-PET (Figure 26). The number of Centers measuring peritoneal permeability using more sophisticated techniques or in another way increased.

The Centers using 3.86%-PET are larger, with a lower drop-out due to UFF/insufficient clearance (Figure 27).

Figure 26: Assessment of peritoneal permeability with the various methods.
Figure 26: assessment of peritoneal permeability with the various methods.
Figure 27: Characteristics of the Centers divided on the basis of assessment of peritoneal permeability adopted and incidence of drop-out due to UFF or poor clearance.
Figure 27: characteristics of the Centers divided on the basis of assessment of peritoneal permeability adopted and incidence of drop-out due to UFF or poor clearance.

PD for heart failure

The Census considers separately new patients to PD on NON renal grounds (GFR > 15 ml/min/1.73m2). The main non-renal reason remains treatment for heart failure (PUF), which regarded 66 patients in 44 Centers in 2022. The data is unchanged with respect to 2010 (Figure 28). In these Centers, with a larger PD program and greater use of Assisted PD, PUF represents 15% of new patients to PD (Figure 29).

Figure 28: Use of PUF (PD in refractory heart failure (HF) at GFR > 15 ml/min/1.73m2) compared with 2010.
Figure 28: use of PUF (PD in refractory heart failure (HF) at GFR > 15 ml/min/1.73m²) compared with 2010.
Figure 29: Characteristics of the Centers which use PD for refractory heart failure (HF).
Figure 29: characteristics of the Centers which use PD for refractory heart failure (HF).

Analysis of the Centers

Mean incidence was 5.9 patients per Center and mean prevalence 18.3 patients per Center, with considerable variability between one Center and another (Figure 30). Most of the Centers involved and of the prevalent patients are concentrated in the North (102 Centers, 45%). Figure 31 shows the geographical distribution.

The 2022 Census considered various aspects which characterize PD Centers. The data is being analyzed and will be published soon.

Figure 30: Distribution of centers and patients by Macro area.
Figure 30: distribution of centers and patients by Macro area.
Figure 31: Breakdown by incidence and prevalence of the PD Centers which took part in the 2022 Census.
Figure 31: breakdown by incidence and prevalence of the PD Centers which took part in the 2022 Census.

 

Discussion

Limitations and new features

The PD Census – at its 8th edition counting 2022 – represents the result of a constant organizational effort by GPDP-SIN and all the PD points of contact in the Centers in Italy using PD. Following the difficulties of the last edition caused by the pandemic, PD Center participation in 2022 was once again 100%.

As has been reiterated several times, its main limitation lies in the fact that it is a photograph of the Centers which perform PD alone, though this is also its raison d’être.

A second limitation results from the growing difficulty the PD points of contact have in sending even the most basic information relating to patients on HD in their Centers. Found for the first time in 2016, the number of Centers not sending HD data reached 22% in 2022.

A third limitation is the calculation of follow-up. With the data available, prevalence at the end of the year, new patients to PD and drop-outs the follow-up has always been calculated by subtracting from and adding to end-of-year prevalence half of the new patients to PD and half of the drop-outs recorded in the year respectively. This system has been preferred to considering the mean between current prevalence and prevalence recorded at the time of the previous Census (a system only used in calculating the incidence of EPS) due both to the interval in between, at times 3 or more years, and – at least initially – the lack of historical data. As usual, however, we report the absolute patient and event values so that anyone who wishes to perform recalculations can do so. It should be remembered only that the system adopted is the most “anti-economic” in that it leads to an underestimation of the follow-up, and therefore an overestimation of the incidence of events. Despite this, it has been shown that the results of PD in Italy are more than valid.

The most important new feature is represented by the new system for collecting the data by means of a dedicated program that can be used to send it in aggregate form. This system has greatly reduced data incongruence and has increased the information available, enabling increasingly detailed processing. As it is not yet used by all the Centers, however, traditional calculation and processing methods have been applied in this edition to all the Centers.

Use of PD

The number of incident and prevalent patients on PD is decreasing: compared to 2016, in 2022 there was a fall in the total number of incident patients of 15.4%, and in the number of prevalent patients of 9.9%. Percentage incidence and prevalence – calculated only for the Centers which sent HD data – are also dropping: compared to 2016, incidence fell from 24.0% to 19.8% and prevalence from 17.4% to 14.9%. It should be remembered furthermore that these percentage values refer only to the Centers using PD. If the number of prevalent patients on PD in 2022 is related to dialysis (HD + PD) prevalence data in Italy (estimated by the Italian Dialysis and Transplant Register to be 811 patients per million inhabitants (pmp) for 2019 [9]), then PD prevalence in Italy is 8.7% (Figure 32), which is disheartening in comparison with other Western countries (Figure 33) (Figure 36 – A) [1013], where the percentage prevalence is higher, not diminishing, and at times continuously increasing, as in the USA.

The reduction in prevalence has involved different regions and macro-areas to a variable degree (Figure 34) (Figure 35).

Figure 32: PD pmp prevalence in relation to the total (HD + PD) reported by the Italian Dialysis and Transplant Register.
Figure 32: PD pmp prevalence in relation to the total (HD + PD) reported by the Italian Dialysis and Transplant Register. The percentages show the relationship between the two prevalences. It is to be remembered that, unlike RIDT, the Census does NOT include pediatric patients.
Figure 33: Trend in percentage PD prevalence reported by the main international registers.
Figure 33: trend in percentage PD prevalence reported by the main international registers.
Figure 34: Comparison between 2022 and 2016 of prevalence referred to the resident populations in the various Italian Macro areas.
Figure 34: comparison between 2022 and 2016 of prevalence referred to the resident populations in the various Italian Macro areas.
Figure 35: Comparison between 2022 and 2016 of absolute value prevalence and referred to the resident populations in the various Italian Regions.
Figure 35: comparison between 2022 and 2016 of absolute value prevalence and referred to the resident populations in the various Italian Regions.
Figure 36: International comparisons.
Figure 36: international comparisons. In A absolute value and percentage prevalence reported by several registers. Canada includes Québec since 2020. Scandinavia includes Denmark, Iceland, Sweden, Norway, Finland. In B the outcome data reported by the Registers in France and ANZ.

Incremental Dialysis

Incremental Dialysis has been investigated ever since the first edition, documenting its characteristics and evolution over time in a manner which is detailed, and still unique – in terms of national Registers – in literature [14]. In 2022 this method grew further due to its greater use in the Centers that already prescribed it, and it seems to increasingly affect the choice of PD method: CAPD for the incremental prescription and APD for full-dose PD. Its use associated with a higher percentage use of PD is confirmed, while an important – but not yet resolved – aspect remains its role in the constant decrease observed in the incidence of peritonitis. Dr. Valerio Vizzardi of the Brescia Center, who has extensive experience in the use of this prescription, examines its importance and limitations in a dedicated annex to this report.

Assisted PD

This aspect will also be considered separately, though a significant reduction in recourse to Assisted PD is seen for 2022.

As is the case with other aspects, assisted PD is used more in larger Centers. The most common caregiver by far is a family member. In this, the situation in Italy is consistent with that in other countries, except – as is well-known and has already been extensively discussed previously – for France.

Drop-out from PD

The improvement seen in mortality is confirmed in 2022, while transfer to HD and transplant remain substantially unchanged. Excluding 2019, the year in which the Census was conducted at the height of the pandemic and was as a result incomplete in terms of both number of Centers taking part and information received, it is the first time drop-outs from PD have fallen below 30 episodes per 100 patient years.

Very little register data is available. Compared with ANZ and France, the Italian rate of turnover is the lowest, and mortality is comparable if not better, although burn-out (voluntary withdrawal from dialysis) is significantly lower than in other countries (Figure 36 – B).

Highlighted in terms of causes of drop-out to HD is an increase in catheter malfunction and the impossibility to continue PD. The fact that the data for the latter differ from France and ANZ is likely to be due to their more limited definition of the category.

A possible association with the lesser role of the Nephrologist in placement and the less frequent recourse to Assisted PD recorded in 2022, however appealing, remains to be established.

The reduction over the years in drop-out due to peritonitis is confirmed, consistent with the decrease observed in the incidence of peritonitis.

Finally, if drop-outs due to insufficient clearance and UFF are considered together, they are superimposable with the situation in other countries (Figure 36 – B).

Peritonitis

The incidence of peritonitis fell in 2022 to 0.176 episodes/patient year. Essentially, it has dropped from 5 episodes per patient-year in the 80s to less than 1 episode every 5 years. In particular, the incidence of peritonitis has almost halved from the first Census in 2005 (1 episode every 36 months) to today (1 episode every 68 months). This value is among the lowest recorded in the West, and is markedly lower than the maximum target recommended by the 2022 ISPD guidelines [15] and consistent with world trends for this complication (Figure 37) [16].

As regards the etiology too, which was investigated in a complete manner for the first time, the Census data are consistent with what has been observed in other Registers and multi-center studies [1719].

Andamento delle peritoniti nel tempo. Dati di Registro ricavato da Marshall et al [16].
Figure 37: trend in peritonitis over time. Register data sourced from Marshall et al [16]. The maximum ISPD – 2022 guideline targets are reported, along with the comparison with the GPDP Census data.
EPS

The 2022 data seem to confirm the major reduction in this PD complication, limited as it was to just a few cases in PD and in HD. This data is controversial – and in certain respects dangerous – because it could lead to less attention being given to the complication in PD to be feared most, so it was worthy of the in-depth analysis carried out by Prof. Guido Garosi and Dr. Nicoletta Mancianti attached to the Report.

Assessment of peritoneal permeability

The monitoring of peritoneal permeability, and the way in which it is done, is an important PD program quality indicator. The Census data show a constant increase over the years in the use of 3.86%-PET, from 15.6% of the Centers in 2010 to 57.7% in 2022. Contributing to this success has certainly been the research carried out by Dr. Vincenzo La Milia, who has examined the reasons in an annex to the Report.

PD due to refractory heart failure

When terminal-stage heart failure is reached, treatment of congestion by means of PD represents a possible solution which was already proposed many years ago. The experience reported in literature [2021] shows clear positive effects on symptomatology, quality of life and admissions to hospital. Indications on when to start the therapy still remain uncertain, and a real comparison with HD is practically impossible, although the data do not show significant differences. The Census highlights an important aspect associated with this therapy. Over a period of more than 10 years, its use in Italy remains relegated to the same number of Centers and for the same number of patients. The Centers that use it are larger and make greater use of assisted PD. 

Center Effect

The number of Centers which use PD has remained substantially the same over the years. In various aspects of PD examined (Incr-PD, drop-out to HD, assisted PD, non-renal PD, PET), it seems that the so-called “Center effect” – in short, size of PD program (prevalent patients) – is important: the larger the program, the better the use and results of PD seem to be. The 2022 Census investigated in greater detail the characteristics of Centers, such as the presence of dedicated doctors and nurses, the availability of dedicated premises and of a home visit program, training methods. A detailed analysis of this important aspect is underway for forthcoming publication.

 

Conclusions

The PD Census relating to 2022 confirms the quality of PD in Italy in terms of prescription elasticity, reduction in mortality, reduction in peritonitis and EPS, the still extensive recourse to Assisted PD, although this is on the decrease, and monitoring of the peritoneal membrane. However, the use of PD seems to be diminishing. Limited as it is to PD Centers, the Census does not make it possible to identify the reasons for this fall. It just highlights its contrast with the results obtained. Thanks to the active participation of the PD contacts in the individual Centers, the Census confirms itself as a valid, constantly-developing tool for knowing the actual situation.

 

Acknowledgements

Special thanks to the contacts in the Centers taking part in the Census, whose commitment has made the collection of the data and this report possible.

Abdulsattar Giamila (Oristano)
Alberghini Elena (Cinisello Balsamo)
Albrizio Paolo (Voghera)
Alessandrello Maria Grazia Ivana (Modica)
Alfano Gaetano (Modena)
Amar Karen (Cernusco sul Naviglio)
Ambrogio Antonina (Rovigo)
Ancarani Paolo (Sestri Levante)
Angelini Maria Laura (forlì)
Ansali Ferruccio (Civitavecchia)
Apponi Francesca (Frosinone)
Argentino Gennaro (Napoli)
Avella Alessandro (Varese)
Barattini Marina (Massa)
Barbera Vincenzo (Colleferro)
Basso Anna (Padova)
Bellotti Giovanni (Sapri)
Benozzi Luisa (Borgomanero)
Bermond Francesca (Torino)
Bianco Beatrice (Verona)
Bigatti Giada (Sesto San Giovanni)
Bilucaglia Donatella (Torino)
Boccadoro Roberto (Rimini)
Boito Rosalia (Crotone)
Bonesso Cristina (San Donà di Piave)
Bonincontro Maria Luisa (Bolzano)
Bonvegna Francesca (Verbania)
Borettaz Ilaria (Melegnano – Vizzolo Predabissi)
Borrelli Silvio (Napoli)
Bosco Manuela (Gorizia)
Braccagni Beatrice (Poggibonsi)
Budetta Fernando (Eboli)
Cabibbe Mara (Milano)
Cabiddu Gianfranca (Cagliari)
Cadoni Maria Chiara (San Gavino Monreale)
Campolo Maria Angela (Lamezia Terme)
Cannarile Daniela Cecilia (Bologna)
Cannavo’ Rossella (Firenze)
Canonici Marta (Fabriano)
Cantarelli Chiara (Parma)
Caponetto Carmelo (Siracusa)
Cappadona Francesca (Genova)
Cappelletti Francesca (Siena)
Caprioli Raffaele (Pisa)
Capurro De Mauri Federica Andreana (Novara)
Caria Simonetta (Quartu Sant’ Elena)
Carta Annalisa (Nuoro)
Caselli Gian Marco (Firenze)
Casuscelli di Tocco Teresa (Messina)
Cataldo Emanuela (Altamura)
Cernaro Valeria (Messina)
Cerroni Franca (Rieti)
Ciabattoni Marzia (Savona)
Cianfrone Paola (catanzaro)
Cimolino Michele (Pordenone)
Comegna Carmela (Tivoli)
Consaga Marina (Livorno)
Contaldo Gina (Monza)
Conti Paolo (Arezzo)
Cornacchia Flavia (Cremona)
Cosa Francesco (Legnano)
Cosentini Vincenzo (San Bonifacio)
Costantini Luigia (Vercelli)
Costantino Ester Grazia Maria (Manerbio)
Costanza Giuseppa (Gela)
D’Alonzo Silvia (Roma)
D’Altri Christian (Martina Franca)
D’Amico Maria (Erice)
De Blasio Antonietta (Caserta)
Del Corso Claudia (Pescia)
Della Gatta Carmine (Nola)
D’Ercole Martina (La Spezia)
Di Franco Antonella (Barletta)
Di Liberato Lorenzo (Chieti)
Di Loreto Ermanno (Atri)
Di Renzo Brigida (Brindisi)
Di Somma Agnese (San Marco Argentano)
Di Stante Silvio (Pesaro – Fano)
Dinnella Angela Maria (Anzio)
Distratis Cosimo (Manduria)
Dodoi Diana Teodora (Chieri)
Domenici Alessandro (Roma)
Esposito Samantha (Grosseto)
Esposito Vittoria (Pavia)
Farina Marco (Lodi)
Ferrando Carlo (Cuneo)
Ferrannini Michele (Roma)
Ferrara Gaetano (San Giovanni Rotondo)
Figliano Ivania Maria (Vibo Valentia)
Figliola Carmela (Gallarate)
Filippini Armando (Roma)
Finato Viviana (San Miniato)
Fiorenza Saverio (Imola)
Frattarelli Daniele (Roma Ostia)
Gabrielli Danila (Aosta)
Gai Massimo (Torino)
Garofalo Donato (Fermo)
Gazo Antonietta (Vigevano)
Gennarini Alessia (Bergamo)
Gherzi Maurizio (Ceva)
Giancaspro Vincenzo (Molfetta)
Gianni Glauco (Prato)
Giovannetti Elisabetta (Camaiore)
Giovannetti Elisabetta (Lido di Camaiore)
Giozzet Morena (Feltre)
Giuliani Anna (Vicenza)
Giunta Federica (Macerata)
Graziani Romina (Ravenna)
Guizzo Marta (Castelfranco Veneto)
Heidempergher Marco (Milano)
Iacono Rossella (Civita Castellana)
Iadarola Gian Maria (Torino)
Iannuzzella Francesco (Reggio Emilia)
Incalcaterra Francesca (Palermo)
La Milia Vincenzo (Lecco)
Laudadio Giorgio (Bassano del Grappa)
Laudon Alessandro (Trento)
Lenci Federica (Ancona)
Leonardi Sabina (Trieste)
Lepori Gianmario (Olbia)
Leveque Alessandro (Citta’ di Castello)
Licciardello Daniela (Acireale)
Lidestri Vincenzo (Chioggia)
Lisi Lucia (Vimercate)
Lo Cicero Antonina (San Daniele del Friuli )
Luciani Remo (Roma)
Maffei Stefano (Asti)
Magnoni Giacomo (Bologna)
Malandra Rossella (Teramo)
Manca Rizza Giovanni (Pontedera)
Mancuso Verdiana (Agrigento)
Manfrini Vania (Seriate)
Manini Alessandra (Crema)
Marcantoni Carmelita (Catania)
Marchetti Valentina (Lucca)
Marini Alvaro (Popoli)
Martella Vilma (Lecce)
Masa Maria Alessandra (Sondrio)
Mastrippolito Silvia (Lanciano)
Mastrosimone Stefania (Treviso)
Matalone Massimo (Catania)
Mauro Teresa (Corigliano Rossano)
Mazzola Giuseppe (Mantova)
Melfa Gianvincenzo (Como)
Messina Antonina (Catania)
Miglio Roberta (Busto Arsizio)
Miniello Vincenzo (Pistoia)
Mollica Agata (Cosenza)
Montalto Gaetano (Taormina)
Montanari Marco (Ariccia)
Montemurro Vincenzo (Firenze)
Musone Dario (Formia)
Nardelli Luca (Milano)
Neri Loris (Alba)
Orani Maria Antonietta (Milano)
Palmiero Giuseppe (Napoli)
Palumbo Roberto (Roma)
Panuccio Vincenzo Antonio (Reggio Calabria)
Panzino Antonio Rosario (Catanzaro)
Parodi Denise (Arenzano)
Pastorino Nadia Rosa (Novi Ligure)
Pellegrino Cinzia (Cetraro)
Perilli Luciana (Vasto)
Perna Concetta (Cerignola)
Perosa Paolo (Pinerolo)
Pieracci Laura (Imperia)
Pietanza Stefania (Putignano)
Pignone Eugenia (Torino)
Pinerolo Maria Cristina (Milano)
Piraina Valentina (ivrea)
Pirrottina Maria Anna (San Benedetto del Tronto)
Pisani Antonio (Napoli)
Pogliani Daniela Rosa Maria (Garbagnate Milanese)
Porreca Silvia (Bari)
Pozzi Marco (Desio)
Prerez Giuseppina (Dolo)
Previti Antonino (Santorso)
Puliti Maria Laura (Palestrina)
Randone Salvatore (Avola)
Ricciardi Daniela (Castiglione del Lago)
Ricciatti Annamaria (Ancona)
Rocca Anna Rachele (Roma)
Rubini Camilla (Venezia Mestre)
Russo Francesco Giovanni (Scorrano)
Russo Roberto (Bari)
Sabatino Stefania (Udine)
Sacco Colombano (Biella)
Sammartino Fulvio Antonio (Pescara)
Santarelli Stefano (Jesi)
Santese Domenico (Taranto)
Santinello Irene (Piove di Sacco)
Santirosi Paola Vittori (Foligno-Spoleto)
Santoferrara Angelo (Civitanova Marche)
Saraniti Antonello (Milazzo)
Savi Umberto (Belluno)
Scalso Berta Ida (Cirie’)
Scarfia Rosalia Viviana (Caltagirone)
Serriello Ilaria (Roma)
Signorotti Sara (Cesena)
Silvana Baranello (Campobasso)
Somma Giovanni (Castellamare di Stabia)
Sorice Mario (Senigallia)
Spissu Valentina (Sassari)
Stacchiotti Lorella (Giulianova)
Stucchi Andrea (Milano)
Taietti Carlo (Treviglio)
Tata Salvatore (Venezia)
Teri Antonino (Foggia)
Tettamanzi Fabio (Tradate)
Timio Francesca (Perugia)
Todaro Ignazio (Piazza Armerina)
Toriello Gianpiero (Polla)
Torraca Serena (Salerno)
Trepiccione Francesco (Napoli)
Trubian Alessandra (Legnago)
Turchetta Luigi (Cassino)
Vaccaro Valentino (Alessandria)
Valsania Teresa (Piacenza)
Vecchi Luigi (Terni)
Veronesi Marco (Ferrara)
Visciano Bianca (Magenta)
Viscione Michelangelo (Avellino)
Vizzardi Valerio (Brescia)
Zanchettin Gianantonio (Conegliano)
Zeiler Matthias (Ascoli Piceno)

 

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  21. Timóteo AT, Mano TB. Efficacy of peritoneal dialysis in patients with refractory congestive heart failure: a systematic review and meta-analysis. Heart Fail Rev. 2023 Feb 4. https://doi.org/10.1007/s10741-023-10297-3.

Omentopexy in Peritoneal Catheter Malfunction

Abstract

Among the various problems associated with peritoneal dialysis, besides infectious causes, the risk of catheter malfunction plays a significant role in conditioning the continuation of the method, accounting for up to 15-18% of the total causes of dialysis drop-out. When non-invasive maneuvers, such as the use of laxatives to stimulate intestinal peristalsis or heparin and/or urokinase have no effect, videolaparoscopy is the only method that directly detects the precise causes of peritoneal catheter malfunction. Those found are, with decreasing frequency, the winding of the catheter between the intestinal loops and the omentum (wrapping), the dislocation of the catheter, the combination of wrapping and dislocation, the occlusion of the catheter by a fibrin plug, the adhesions between the intestine and abdominal wall, the occlusion of the catheter by epiploic appendages or adnexal tissue and, occasionally, the presence of a new formation of endoperitoneal tissue enveloping and obstructing the peritoneal catheter. We report the case of a young patient of African ethnicity who, only five days after catheter placement, experienced malfunction. A videolaparoscopy revealed wrapping with invagination of omental tissue inside the catheter. After omental debridement, a proper peritoneal cavity washout with heparin was resumed, and after a couple of weeks, APD was initiated. About a month later, a new malfunction without signs of coprostasis or problems with the abdominal radiogram was observed. However, a subsequent catheterography confirmed the blockage of drainage. This was followed by another catheterography and omentopexy, with definitive solution of the Tenckhoff malfunction.

Keywords: peritoneal dialysis, peritoneal catheter, omentopexy

Sorry, this entry is only available in Italian.

Introduzione

La dialisi peritoneale rappresenta un’opzione dialitica in cui l’accesso alla cavità addominale rimane uno dei punti più importanti sia per la sopravvivenza della tecnica [1] che per la dislocazione o l’infezione del catetere, quali principali cause di fallimento della metodica. Un problema collegato all’accesso suddetto è rappresentato sicuramente dal malfunzionamento del catetere che, se si verifica, comporta l’impossibilità di eseguire in maniera adeguata la dialisi peritoneale, condizionando la sopravvivenza tecnica del catetere e spesso anche il proseguimento della metodica dialitica stessa [24]. Il rischio di malfunzionamento del catetere peritoneale è di circa il 15-18% l’anno [5, 6]. Le tecniche di posizionamento che prevedono l’esecuzione di procedure quali l’omentectomia, l’omentopessi [711], la tunnellizzazione nel retto o la fissazione intra-addominale, sembrano presentare una ridotta insorgenza di malfunzionamento [12, 13]. È opinione condivisa che il catetere peritoneale “ideale” dovrebbe quantomeno assicurare un rapido flusso bidirezionale senza comparsa di complicanze (leakage o infezioni) e che non esista in realtà una variante di catetere superiore all’altra, conferendo al nefrologo la scelta decisiva del tipo di catetere; queste caratteristiche sono sempre state tipiche del catetere originale di Tenckhoff e le sue varianti, proposte successivamente nel tentativo di ridurne le comunque possibili complicanze.

Accanto al classico catetere di Tenckhoff, ideato nel 1968, oggi troviamo tutta una serie di varianti che possono personalizzare la scelta del nefrologo. Il materiale usato è il silicone dotato di minor azione irritante rispetto al polivinile o altri materiali in precedenza utilizzati, atraumatico per i tessuti circostanti, morbido, flessibile e privo di plasticizzanti rilasciabili clinicamente dannosi. Nella forma per l’adulto la lunghezza complessiva è di circa 40 cm, strutturata in un segmento intraperitoneale diritto munito di multipli forellini, un segmento transparietale o intramurale, un segmento sottocutaneo ed un segmento esterno o extra-addominale; il diametro interno è di 2,6 mm; due cuffie di poliestere (Dacron), una profonda intramurale ed una superficiale sottocutanea, lo ancorano ai tessuti; una striscia radiopaca ne permette infine una facile identificazione radiologica in caso di dislocazioni o rotture accidentali. Nel corso degli anni sono state proposte numerose varianti tanto da avere attualmente a disposizione sul mercato diverse combinazioni per quanto riguarda il numero delle cuffie (1 o 2), la configurazione dell’estremità intraperitoneale diritta (straight) o a spirale (coiled), la conformazione del tratto sottocutaneo del catetere diritta o precurvata a “collo di cigno” (swan-neck), la presenza infine di dispositivi atti a impedire la dislocazione del tratto intraperitoneale. Una variante ampiamente usata è, appunto, il catetere Swan-Neck, ovvero un Tenckhoff classico caratterizzato tuttavia da una precurvatura del tratto sottocutaneo compreso fra le due cuffie con un angolatura di 170°-180°, tale da ricordare la sinuosità del collo di cigno che consente di direzionare verso il basso l’uscita del catetere agevolando il drenaggio verso l’esterno di eventuali secrezioni, riducendo così le complicanze infettive dell’exit site ed annullando la memoria elastica del catetere riducendo la dislocazione. Un’altra variante è il catetere Toronto Western Hospital (TWH), un Tenckhoff caratterizzato dalla presenza di due dischi di silicone posizionati perpendicolarmente nell’ultima porzione del tratto intraperitoneale del catetere con il duplice scopo di tenere lontani l’omento e le anse intestinali dai forellini di deflusso e di minimizzare la migrazione del tip; gli svantaggi includono una maggiore difficoltà nell’impianto e nella rimozione del catetere dell’estremità intraperitoneale e l’estrusione della cuffia superficiale. Altra variante il catetere a T di Ash e Janlel, con una porzione intraperitoneale, posizionata a contatto con il peritoneo parietale e che presenta, anziché i forellini laterali, 8 ampie scanalature a becco di flauto; le scanalature e la forma a T garantirebbero rispettivamente un miglior flusso e minori problemi di dislocazione. Altra variante è il catetere autolocante di Di Paolo, un Tenckhoff diritto caratterizzato da un piccolo cilindro di tungsteno dal peso di 12 grammi incorporato nell’estremità intraperitoneale del catetere; un tale “appesantimento” ne impedirebbe la dislocazione al di fuori della pelvi ma protrebbe provocare decubito. Un aspetto che sicuramente incide sulla scelta del tipo di catetere è la sua lunghezza che può variare in funzione della conformazione fisica del paziente: il catetere Swan-Neck, indicato nei pazienti obesi, con uscita presternale è una variante con estremità a spirale, composto da due cateteri in silicone collegati fra di loro in modo termino-terminale da un raccordo di titanio: la parte inferiore costituisce il segmento intra-addominale e parte del segmento intramurale, quello superiore o toracico costituisce la rimanente parte del segmento intramurale e tutto il tunnel sottocutaneo dotato di 2 cuffie di Dacron. Altra variante è il Vicenza cath, un catetere di Tenckhoff diritto a doppia cuffia caratterizzato da una minor lunghezza del tratto intraperitoneale (8 cm vs 15 cm) rispetto al modello originale, ideato dal gruppo di Vicenza ed indicato per l’infissione in sede sovrapubica nell’intento di limitare il rischio di intrappolamento omentale e sua dislocazione.
Oltre alla sede dell’exit-site e al tipo di catetere, è l’omento che gioca un ruolo fondamentale sia per la dialisi peritoneale che per l’equilibrio della cavità addominale e dei suoi visceri. Esso è una formazione sierosa che avvolge gli organi addominali e si distingue in “grande omento” (o grande epiploon o epiploon gastro-colico), plicatura del peritoneo viscerale ed infiltrato di adipe estesa dallo stomaco al colon trasverso che ricopre la massa intestinale a guisa di grembiule, e “piccolo omento” che unisce lo stomaco al fegato.
Il piccolo omento stabilizza i vari organi e veicola alcuni vasi (arteria epatica, dotto coledoco, vena porta). Il grande omento costituisce, invece, una sorta di lamina ventrale che protegge tutti o buona parte degli organi della cavità addominale. Un’anamnesi attenta può essere importante per identificare cause di malfunzionamento come la presenza di costipazione, di frustoli di fibrina e di liquido peritoneale ematico durante lo scarico. Inoltre, la stessa posizione che il paziente deve assumere per evitare problemi di drenaggio può essere indicativa della posizione del catetere all’interno della cavità addominale. Una radiografia dell’addome in proiezioni antero-posteriore e laterale ed, eventualmente, anche in posizione supina, è necessaria per verificare la posizione del catetere e per confermare il sospetto di una sua dislocazione o angolazione e per evidenziare un intasamento fecale del colon. In generale, le metodiche di salvataggio del catetere peritoneale malfunzionante possono essere distinte in tecniche non invasive, o conservative, e tecniche invasive che necessitano di un intervento chirurgico. Tra quelle non invasive, l’uso di lassativi (polietilenglicole, macrogol, etc.), favorendo la motilità intestinale, può aiutare a riportare alla posizione ideale il catetere peritoneale. Sempre tra quelle non invasive, nel caso in cui ci siano problemi di carico/scarico legati ad ostruzione intraluminale certa o sospetta, talvolta sono efficaci le manipolazioni intraluminali come l’introduzione di liquido di dialisi a pressione positiva, l’introduzione di eparina o di urochinasi [14] o di spazzolini endoscopici, cateteri ureterali o del catetere di Fogarty. In quelle invasive, la videolaparoscopia rappresenta l’unica vera metodica che rileva in modo diretto le cause di malfunzionamento del catetere peritoneale e permette inoltre una precoce ripresa della dialisi rispetto alla procedura laparotomica in relazione alla sua mininvasività. Quelle riscontrate sono, con frequenza decrescente, l’avvolgimento del catetere tra le anse intestinali e l’omento (omental wrapping) [1518], la dislocazione del catetere, la combinazione di wrapping e dislocazione, l’occlusione del catetere da tappo di fibrina, le aderenze tra l’intestino e la parete addominale, l’occlusione del catetere da appendici epiploiche o da tessuto annessiale. Una neoformazione tissutale endoperitoneale che avvolge ed ostruisce il catetere peritoneale viene riscontrata solo occasionalmente. Una recente revisione sistematica, attraverso una ricerca bibliografica su Medline, EMBASE, Scopus e Cochrane Library ed in accordo con la Cochrane Collaboration, nel febbraio 2021 ha posto l’attenzione su pazienti sottoposti ad inserimento del catetere peritoneale con e senza manipolazione omentale. I risultati, comunque correlati da bassa a moderata qualità dei dati, hanno messo in evidenza che la manipolazione omentale eseguita al momento dell’inserimento del catetere peritoneale, attarverso tecniche di videolaparoscopia, conferisce benefici in termini di ridotta ostruzione e fallimento che ne richiedano successivamente la rimozione [19].

 

Caso clinico

Riportiamo il caso clinico di un paziente di sesso maschile, di etnia africana, di 48 anni, lavoratore metalmeccanico con una storia anamnestica di gozzo multinodulare tossico dall’età di 36 anni ed ipertensione arteriosa nota dall’età di 43 anni. Nel maggio 2021 aveva riscontrato un quadro di malattia renale cronica IV, sino ad allora misconosciuta, da causa ignota (reni ecograficamente piccoli) ma probabilmente ad etiologia nefroangiosclerotica. Ad inizio 2022 aveva rifiutato di iniziare il trattamento emodialitico presso altro centro per poi essere costretto, dopo pochi mesi, ad iniziare l’emodialisi attraverso un catetere venoso centrale temporaneo, sostituito dopo sole 48h dal suo posizionamento per infezione da S. aureus. Il paziente veniva trasferito per competenza territoriale presso il nostro centro per proseguire l’emodialisi e lo stesso, nel corso di un nostro colloquio predialisi, aveva accettato di intraprendere la strada della dialisi peritoneale, data la giovane età ed il tipo di lavoro. Contemporaneamente alla decisione di essere valutato per la dialisi peritoneale, il paziente accettava di iniziare tutti gli esami strumentali ed ematochimici valevoli per il potenziale inserimento in lista d’attesa per trapianto di rene da donatore cadavere (non erano disponibili potenziali donatori viventi). A seguito di riscontro di tampone cutaneo e nasale positivi allo S. aureus, veniva preventivamente sottoposto a terapia antibiotica (vancomicina ev in centro dialisi), anche propedeutica al successivo posizionamento del catetere peritoneale. Dopo un paio di settimane di emodialisi nel nostro centro, veniva sottoposto ad intervento, in anestesia spinale ed in laparotomia, di posizionamento di catetere di Tenckhoff in fossa iliaca destra, con controllo, post procedura chirurgica, radiografico dell’addome che certificava il buon posizionamento dello stesso, in presenza di qualche piccolo frustolo di fibrina ai primi lavaggi successivi all’intervento. Dopo appena 5 giorni dall’intervento, si manifestavano i primi problemi nello scarico del liquido; un radiogramma dell’addome mostrava un corretto posizionamento del catetere in Douglas senza segni di coprostasi. Il lavaggio del cavo peritoneale con l’eparina prima e lo stazionamento dell’urochinasi poi, non sortivano alcun effetto positivo sulla ripresa del drenaggio peritoneale. La successiva radiografia con mezzo di contrasto (gastrografin) dimostrava, invece, l’ostruzione pressoché completa dei fori del catetere di Tenckhoff per cui si programmava un’intervento, in videolaparoscopia, nel corso del quale si provvedeva alla disostruzione del catetere con sbrigliamento omentale e rimozione di alcuni piccoli frammenti di omento all’interno del lume del catetere stesso. Il successivo lavaggio con soluzione eparinata, nei giorni successivi all’intervento, certificava il ritrovato funzionamento del catetere con l’inizio della APD dopo un paio di settimane. A distanza di poco meno di un mese dall’inizio della APD, si presentava un nuovo problema nello scarico del liquido; anche in questo caso la radiografia dell’addome non mostrava dislocamento del catetere né segni evidenti di coprostasi. Ripetuta radiografia addome con mezzo di contrasto, si dimostrava nuovo impaccamento del catetere con fuoriuscita di liquido solo dai primi fori prossimali del catetere. A questo punto il paziente veniva riportato in sala operatoria e sottoposto, sempre in videolaparoscopia, ad intervento di omentopessi (Fig. 1), con la fissazione, attraverso punti di sutura staccati, dell’omento alla parete anteriore del corpo e dell’antro dello stomaco (Fig. 2). Successivamente al secondo intervento, il paziente non ha mostrato ulteriori problemi di drenaggio del liquido peritoneale, potendo riprendere regolarmente la sua attività lavorativa da un lato e quella dialitica peritoneale con APD dall’altro.

Figura 1: Omento rovesciato su corpo gastrico.
Figura 1: Omento rovesciato su corpo gastrico.
Figura 2: Fissazione omento a corpo gastrico.
Figura 2: Fissazione omento a corpo gastrico.

 

Discussione

È indubbio il ruolo del nefrologo nella scelta del tipo di catetere peritoneale con le varianti disponibili in silicone, considerando che nessuna variante del catetere prevalga sull’altra; è altrettanto noto che il posizionamento e la revisione di un catetere peritoneale, o la pura presenza dello stesso, può comportare uno stimolo attivante la proliferazione fibrobastica con neovascolarizzazione, in qualche caso anche di tipo reazione da corpo estraneo [2021]. Il fenomeno può essere recidivante entro breve tempo. Nella gestione del malfunzionamento del catetere peritoneale l’intervento, molto spesso risolutivo (nel 90% circa dei casi), di una procedura invasiva quale è la videolaparoscopia, deve essere considerata dopo aver seguito una sequenza ben definita di procedure non invasive standardizzate. Probabilmente in pazienti selezionati giovani, l’approccio laparoscopico al posizionamento del catetere peritoneale, utilizzando manovre laparoscopiche standardizzate, può essere eseguito con successo con complicanze perioperatorie a breve e medio termine trascurabili e trascurabili tassi di mortalità [22]. In questo caso clinico, l’omento si è comportato come una calamita sul catetere peritoneale, avvolgendolo nella sua interezza ed invaginandosi al suo interno, attraverso i fori della parte finale del catetere, compromettendo la funzionalità della metodica. Sicuramente la giovane età del paziente e la presenza di fibrina, associati al malfunzionamento precoce della funzionalità del catetere potevano essere segnali premonitori su quanto stesse accadendo, sebbene il soggetto non rientrasse in ulteriori categorie a rischio, caratterizzate dalla presenza di diabete mellito pluricomplicato, presenza di epatite, anamnesi di malfunzionamento di accessi vascolari, forte abitudine tabagica o cardiopatia infartuale recente. Il primo sbrigliamento non è bastato a risolvere il problema e solo l’omentopessi, attraverso un secondo intervento in videolaparoscopia, con fissaggio dell’omento al corpo ed antro dello stomaco, ha potuto risolvere definitivamente la natura del malfunzionamento e far riprendere la dialisi peritoneale al giovane paziente, in attesa del trapianto di rene da donatore cadavere. Il caso clinico in questione fa riflettere sulla scelta della tipologia dell’intervento di posizionamento del catetere peritoneale in quei pazienti giovani con bassi fattori di rischio di malfunzionamento; un’iniziale approccio chirurgico laparoscopico, in anestesia generale, avrebbe consentito di evitare quella trafila chiurgica laparotomica mininvasiva resasi necessaria dopo gli episodi recidivanti, a breve distanza fra loro, di malfunzionamento, garantendo una visione più completa dell’anatomia addominale del paziente ed un più preciso posizionamento del catetere nello scavo del Douglas.

 

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