Peritoneal dialysis (PD)-associated peritonitis remains by far the most important complication requiring patients to transfer to hemodialysis and has a major impact on patient morbidity and mortality. Current International Society for Peritoneal Dialysis (ISPD) guidelines on peritonitis recommend analysis of peritonitis episodes only in trained patients. In a large tertiary care center, we analyzed peritonitis episodes accounting for different groups of untrained patients and compared these with episodes in the trained patient population.

We analyzed data collected prospectively over a 15-year time span regarding differences between peritonitis episodes in trained patients and episodes in untrained patients post-catheter insertion but prior to training completion as well as on in-center intermittent PD with respect to incidence rates, pathogenic organisms, outcome, and peritonitis predictors.

In 275 patients, a total of 160 peritonitis episodes in trained patients were counted. A total of 27 additional episodes in untrained patients were recorded. When accounting for these episodes, the peritonitis incidence significantly increased and the percentage of peritonitis-free patients decreased. Peritonitis episodes in untrained patients were most often culture-negative and the pathogen spectrum differed significantly compared with episodes counted as per ISPD recommendations, while outcome of peritonitis episodes did not differ. Predictors of peritonitis after multivariate logistic regression analysis included glomerulonephritis as primary kidney disease, being on home PD rather than being on in-center intermittent PD, and higher dialysis vintage.

Depending on local practice patterns, we argue that centers should additionally monitor peritonitis episodes in untrained patients because computation of statistics as per ISPD recommendations could underestimate peritonitis incidence and may depict a distorted pathogen spectrum.