Long-Term Trends in Microbial Profile and Antimicrobial Resistance in Peritonitis Associated with Continuous Ambulatory Peritoneal Dialysis

Objective: Peritoneal dialysis-associated peritonitis is a major cause of technical failure and transition to hemodialysis, negatively impacting patient morbidity and mortality. This study investigated the frequency of peritonitis, causative agent distribution, and antibiotic susceptibility profiles in patients followed at the Erciyes University Peritoneal Dialysis Unit between 2004 and 2018.Methods: Records of patients aged ≥18 who underwent peritoneal dialysis (PD) and developed peritonitis between January 2004 and December 2018 were retrospectively reviewed. Demographic data, culture results, isolated microorganisms, antibiotic susceptibilities, and treatment outcomes were compiled from patient files and the hospital information management system.Results: This study retrospectively evaluated 677 episodes of peritonitis in 345 patients undergoing peritoneal dialysis. The mean age of the patients was 52.37 ± 14.95 years, and 53.9% were male. Culture positivity was found in 61% of cases; the dominant causative agents were gram-positive bacteria (75.8%), primarily Staphylococcus epidermidis (25.9%). While 76.6% of cases improved with treatment, the mortality rate was recorded as 5.3%. An increase in methicillin resistance was observed in S. epidermidis; all Candida isolates were found to be susceptible to fluconazole. It was determined that the incidence of peritonitis decreased over the years, while the rate of culture negativity increased.Conclusion: In peritoneal dialysis-associated peritonitis attacks, gram-positive microorganisms were found to be the predominant causative agents, and this pattern remained stable throughout a fifteen-year follow-up period, including relapse cases. No significant differences were observed in the pathogen spectrum or antibiotic susceptibility profiles between periods. These findings demonstrate that microbiological data specific to our center can be effectively used in the development of empirical treatment protocols. The increase in culture negativity rates observed in recent years points to the need to review sampling, transport, and laboratory processes. Developing standardized protocols to reduce culture negativity should be among the priority goals for increasing diagnostic accuracy and treatment efficacy.