Evolution of microbiological trends and treatment outcomes in peritoneal dialysis-related peritonitis

Background and aim: Peritoneal dialysis (PD)-related peritonitis is a major risk factor of technique failure and contributes to significant mortality in patients undergoing PD. The aim of this study was to examine the evolution of microbiological trends and treatment outcomes of PD-related peritonitis in our hospital over the past 26 years. Methods: A total of 630 patients entered our CAPD program from February 1984 to June 2010. Among them, 119 patients (18.9%) experienced 599 episodes of peritonitis. Microbiological trends, treatment responses, techniques and patient survival were analyzed. Results: The incidence rate of total peritonitis showed a steady decline from 1.08 episodes/patient-year in 1984 to 0.25 episode/patient-year in 2009 (p < 0.001). A similar trend was found in gram-positive (p < 0.001) and gram-negative peritonitis (p = 0.015). In contrast, there was a trend toward an increased proportion of gram-negative peritonitis. This increase was not due to an increased rate of gram-negative peritonitis but to the more dramatic fall in gram-positive peritonitis. Treatment of peritonitis resulted in a complete cure in 78.0% of patients, while 16.7% of patients required catheter removal and 5.3% died. Gram-positive organisms were associated with a more favorable outcome compared to gram-negative pathogens as manifested by a higher cure rate (p = 0.023). The patient survival and technique survival were much improved after 2000 compared to that before 2000 (p < 0.0001). Conclusion: A remarkable improvement in the outcome of PD-related peritonitis has been achieved in the past 26 years in our hospital. To further decrease peritonitis rates, attention needs to be directed at reducing gram-negative peritonitis.