Péritonites répétées en dialyse péritonéale : Etude de cohorte

Résumé

Introduction : La compréhension des mécanismes physiopathologiques des péritonites répétées, définies comme la survenue d’un nouvel épisode de péritonite plus de 4 semaines après l’arrêt d’une antibiothérapie adaptée pour un épisode précédent impliquant le même germe, reste limitée.

Méthodes : Nous avons étudié les résultats de 26 épisodes de péritonites répétées entre 2006 et 2024 (Groupe Répété) et les avons comparés à 23 épisodes de péritonites récidivantes (Groupe Récidive) et à 84 épisodes de péritonite survenant 4 semaines ou plus après un autre épisode avec un organisme différent (Groupe Témoin).

Résultats : La majorité des épisodes de péritonites répétées sont causés par des organismes à gram positif (65,5 %), principalement dus au Staphylococcus aureus (38,5 %), tandis que la plupart des épisodes de péritonites récidivantes sont à culture négative (69,5 %), suivis d’épisodes de péritonites à bacilles gram négatif (17,4 %). L’infection du site d’émergence est significativement associée à la survenue de péritonite. Les cocci gram positif sont responsables de 95,5 % des infections du site d’émergence principalement dues au Staphylococcus aureus.
Dans le Groupe Répété, 14 (66 %) patients ont obtenu une réponse primaire sous antibiotiques, tandis que la guérison complète a été atteinte chez 10 (47 %) patients , alors que le cathéter de dialyse péritonéale a été retiré chez 3 (14 %) patients dès le premier épisode de péritonite répétée ; cependant, le risque de développer une péritonite récidivante était de 4,7 %, et une péritonite récurrente était de 9,5%.

Conclusion : La définition de la péritonite répétée est claire. Malgré un résultat favorable sous traitement antibiotique, le risque de développer de nouveaux épisodes de péritonite reste élevé, menaçant la survie de la technique et la vie du patient.

Introduction

Peritoneal dialysis (PD) associated-peritonitis is the most common and dreadful complication of PD.

Outcomes of peritonitis vary considerably from one country to another, ranging from cure with antibiotics (69.0-80.7%), catheter removal (10.8-20.4%), or mortality (1.8-6.0%)(Szeto, 2011).

On the other hand, mortality related to peritonitis was defined and reported differently in 55% of studies, with a prevalence ranging from 10% to 20%(Szeto, 2011)(Fried & Bernardini, 1996)(Ye & Zhou, 2017-06-05)(Hassan & Murali, 2022-11).

The International Society of Peritoneal Dialysis (ISPD) 2022 recommendations clearly define repeat peritonitis as an episode of peritonitis occurring more than 4 weeks after the end of antibiotic treatment for a previous episode with the same organism. In contrast, relapsing peritonitis is defined as an episode of peritonitis occurring within 4 weeks of the end of appropriate antibiotic treatment for a previous episode with the same organism, or a sterile episode, and a recurrent peritonitis as an episode that occurs within 4 weeks after completion of therapy but with a different organism(Li et al., 2022).

Regardless of the type of peritonitis, the occurrence of new episodes suggests persistence of infection and may be associated with an increased risk of infectious complications; the prognosis will depend on how quickly the cause is identified and treated.

The aim of this study is to identify patients at risk of developing repeat peritonitis, to understand the associated factors and to assess the outcomes in order to prolong the survival of the technique and to lower morbidity and mortality.

Materials and methods

Patient Selection

From the 2006 opening of our PD unit until January 2024, 235 patients were recruited in our unit.

All episodes of PD peritonitis during this period were carefully considered. (Figure 1)

Figure 1.Example caption for this image

Data was collected by reviewing the French Language Peritoneal Dialysis Registry (RDPLF) database, as well as each patient’s hospital records.

According to the ISPD guidelines(Li et al., 2022), PD peritonitis was diagnosed when at least two of the following are present : 1) abdominal pain and/or cloudy dialysis effluent; 2) dialysis effluent white cell count > 100/μL or > 0.1 x 109 /L (after a dwell time of at least 2 h), with > 50% polymorphonuclear leukocytes (PMN); 3) positive dialysis effluent culture.

In this study and according to ISPD guidelines , we defined repeat peritonitis as an episode that occurs more than 4 weeks after completion of therapy of a prior episode with the same organism.

In the 18 years of the study period, 378 episodes of PD peritonitis (in 9 389 patient-months of treatment) were recorded in our unit. 26 episodes (6.8%) were repeat peritonitis. The result is compared with 23 episodes of relapsing peritonitis during the same period (the Relapse Group), and 84 episodes of peritonitis which had been preceded by another episode caused by a different organism 4 weeks to 24 months (the Control Group). We excluded culture-negative and polymicrobial episodes while selecting the control episodes.

The demographic characteristics, underlying medical conditions, previous PD peritonitis, catheter removal, and clinical outcome were also examined.

Microbiological investigation

Bacterial culture of the dialysate fluid was performed on Chapman and/or chocolate agar, and on Cystine–lactose–electrolyte-deficient (CLED) and blood agar.

Clinical management

PD peritonitis episodes were treated according to the standard antibiotic protocol of our center at the time, which was systematically modified over time.

We initially administer Ceftazidime and Cefazolin IP or IV, plus an aminoglycoside. Antibiotic regimens for individual patients were modified when culture results were available, and the peritoneal dialysis effluent was regularly inspected. Antibiotic therapy was continued for a total of 14 days for episodes caused by Staphylococcus coagulase negative and 21 days for episodes caused by gram negative bacillus or Staphylococcus aureus.

Primary response was defined clinically as the resolution of abdominal pain, clarification of dialysate on day 5 with antibiotics alone.

Complete cure was defined as complete resolution of PD peritonitis with antibiotics alone without relapse or recurrence within 4 weeks after completion of treatment. The Tenckhoff catheter was removed only after staff discussion. If the catheter is removed, antibiotics are maintained for an additional two weeks . If reinsertion of a new catheter was contraindicated, we consider it as a technique failure and the patient transferred to long term hemodialysis.

Statistical Analysis

Qualitative variables were expressed as numbers and percentages, and compared using the chi-square test. Quantitative variables were expressed either as the mean ± standard deviation (SD)

if the distribution of the variable was normal, and compared using the t student or ANOVA , or as the median with the interquartile range if the distribution of the variable was asymmetric.

Statistical analyses were performed using Jamovi 2.3.21

Results

In our study, 96 patients were included ,with a sex ratio of 1.4 (M/F), while the mean age was 50 ±17,3 years.

While 79,2% of our patients were on Continuous ambulatory peritoneal dialysis (CAPD), 85.4% were autonomous.

Of all our patients, 21 (Repeat Group) developed a repeat peritonitis, 19 patients (Relapse Group) developed relapsing peritonitis, and 56 patients (Control Group) had an episode of peritonitis which had been preceded 4 weeks to 24 months by another episode caused by a different organism.

The baseline clinical characteristics at the time of PD peritonitis of the patients are summarized inTable I. There is no significant difference in the baseline clinical characteristics between groups.

.....