The microbiological epidemiology of infections in peritoneal dialysis over a 45-year period in the Peritoneal Dialysis Registry in France (RDPLF)

Abstract

Infectious peritonitis remains a frequent complication of peritoneal dialysis. Over the years, numerous technical advancements have been introduced, aimed at both reducing the incidence of these infections and enhancing their microbiological characterization. In this study, we analyzed 26,235 peritonitis episodes recorded in the French-Language Peritoneal Dialysis Registry (RDPLF) database to describe the evolution of infectious epidemiology from the 1980s to the present day.
Our findings reveal a marked decrease in the proportion of staphylococcal infections between 1978 and 2010. Conversely, infections caused by Enterobacteriaceae, enterococci, and streptococci have progressively increased over the same period. The modality of peritoneal dialysis appears to be associated with specific bacterial profiles: infections involving skin flora are more prevalent in continuous ambulatory peritoneal dialysis, whereas those of environmental or mixed (oral/gastrointestinal) origin are more frequently observed with automated peritoneal dialysis.
The advent of advanced diagnostic techniques, particularly molecular biology methods, has significantly improved the microbiological documentation of peritonitis, especially for organisms that are non-cultivable or difficult to culture by conventional laboratory methods.
In summary, this study presents the microbiological trends observed in peritoneal dialysis-associated peritonitis in France from the 1980s to the present, based on data from over 20,000 patients included in the RDPLF database, and highlights the impact of evolving technological approaches on the detection and understanding of these infections.

INTRODUCTION

The prevalence of chronic kidney disease is currently estimated at 8-10% of the French population, with the total number of dialysis and transplant patients rising sharply (+25%) between 2012 and 2020¹². In France, the use of the peritoneum as a dialysis membrane for treating these patients dates back to the 1950s, with the introduction of intermittent peritoneal dialysis (IPD), followed in the late 1970s by continuous ambulatory peritoneal dialysis (CAPD), and finally automated peritoneal dialysis (APD) in the 1980s. The use of APD or CAPD facilitates patient autonomy and is an alternative to hemodialysis³. One of the main complications of these techniques is infection, and peritonitis is the most frequent cause of discontinuation of peritoneal dialysis, associated with significant morbidity and mortality⁴. Nevertheless, while the frequency of peritonitis was on the order of one episode every 2 to 3 months in the early 1980s, it is now on the order of one episode every 2 to 5 years⁵. The prevalence of these infections and the bacteria associated with them varies greatly between care centers, even within the same country, making comparisons between them difficult to interpret⁶⁷⁸. The Registre de Dialyse Péritonéale de Langue Française (French-Language Peritoneal Dialysis Registry, RDPLF) database brings together data from patients treated with home peritoneal dialysis since the early 1980s in several French-speaking countries. Over the last five decades, major technical developments have taken place concerning peritoneal dialysis and associated equipment on the one hand and microbiological analyses on the other. Here, we present the microbiological changes observed in peritonitis associated with peritoneal dialysis from the 1980s to the present day, using data from more than 20,000 patients and in light of these technological advances.

MATERIALS AND METHODS

This is a retrospective multicenter study based on data from the RDPLF.

Using the REIN registry, which is managed by the Agence de Biomédecine in France, as a reference, the completeness of the RDPLF is currently estimated to cover more than 90% of all patients treated with peritoneal dialysis in France.

The inclusion period was from July 1978 to February 2023, and only French data were included. Events corresponding to peritonitis in patients receiving peritoneal dialysis were selected.

Peritonitis cases without peritoneal dialysate sampling, occurring after cessation of peritoneal dialysis, of non-infectious cause, or without microbiological documentation were excluded.

The following data were collected: sex, age, region of care, presence of diabetes, date of start of dialysis, type of dialysis, date of onset of peritonitis, and bacteria detected.

The proportions of episodes corresponding to the variables of interest were analyzed by Fisher's exact test or the chi-square test with alpha set at 0.05. Comparisons of age between populations or dialysis durations were made with a parametric one-way ANOVA test with alpha set at 0.05. The calculations were performed using GraphPad Prism software version 10.5.0 (GraphPad Software).

RESULTS

1. Extraction of results

A total of 32,503 episodes were extracted from the RDPLF. Among these, 328 episodes were excluded for a lack of dialysate sampling, 304 for inconsistent time to onset of peritonitis, 146 for documented non-infectious cause, and 5387 for lack of microbiological documentation. A total of 26,325 peritonitis events corresponding to 20,479 patients were included (Figure 1).

Figure 1.Inclusion process for peritonitis events

2. Population analysis

Table I.Characteristics of the cohort

	Male	Female
Number of patients	11,768	8711
Number of episodes of 1st peritonitis	20,479
Number of peritonitis recidives	3414	2432
Diabetes	1404	1073
Peritonitis on dialysis after transplant rejection	780
	Median
Age of patients at time of peritonitis	69 (25th to 75th percentiles: 57; 78)	68 (25th to 75th percentiles: 55; 78)
Age at time of peritonitis before 1980	53 (25th to 75th percentiles: 50; 71)
Age at peritonitis 1980-1989	61 (25th to 75th percentiles: 57; 76)
Age at onset of peritonitis 1990-1999	68 (25th to 75th percentiles: 57; 79)
Age at onset of peritonitis 2000-2009	71 (25th to 75th percentiles: 57; 79)
Age at onset of peritonitis 2010-2019	70 (25th to 75th percentiles: 57; 80)
Age at peritonitis 2020 and later	70 (25th to 75th percentiles: 59;78)

The main characteristics of the cohort population (age, number of patients, comorbidities, etc.) are summarized inTable I. The sex ratio was 1.4, and there were four times more documented first episodes of peritonitis than recidives. The presence of diabetes as a comorbidity was found in 12% of patients, irrespective of gender. The median time to onset of peritonitis rose from around 12 months in the 1970s to over 35 months in the 2010s (Figure 2). The median age of onset of peritonitis also changed over the decades, rising from around 50 years in the 1970s to 70 years in the 2010s (Figure 3), but no significant difference was observed between first episodes of peritonitis and recidives. The median age of onset was nevertheless significantly earlier in the female population (Figure 4A; p<0.0001). The other factor influencing the age of onset of infectious episodes was the type of peritoneal dialysis, with a significantly higher age in the population managed by CAPD compared to APD (p<0.0001) (Figure 4B).

Figure 2.Median time to onset of peritonitis over time

Figure 3.Age of onset of peritonitis as a function of time

Figure 4.(A) Age at onset of peritonitis according to gender (B) Comparison

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