Peritoneal Dialysis-Related Peritonitis: A Matched Comparative Analysis.

Rationale & Objective: () is a coagulase-negative staphylococcus species that has been increasingly recognized to cause serious infections with virulence resembling s (). No studies have evaluated the characteristics and outcomes of patients with peritoneal dialysis-related peritonitis compared with those with peritonitis. We aim to evaluate the clinical course of peritonitis as caused by these organisms.

Study Design: A retrospective matched comparative analysis involving a single tertiary center from July 2000 to July 2020.

Setting & Participants: Forty-eight episodes of peritonitis were matched to 19 cases of peritonitis.

Analytical Approach: The cases were individually matched for year of peritonitis, sex, age (±10 years), and Charlson Comorbidity Index (±3). A comparative analysis was performed between the 2 organisms. The outcome includes responses at day 5 of peritonitis and the rate of complete response.

Results: There is a higher predilection of diabetes in those with peritonitis than in those with (64.6% vs 31.6%;  = 0.03). Patients with peritonitis also have a much higher total cell count at presentation (4,463.9 ± 5,479.5 vs 1,807.9 ± 3,322.7;  = 0.05); a higher prevalence of poor response at day 5 (50.0% vs 15.8%;  = 0.03); a lower rate of complete response (64.6% vs 94.7%;  = 0.01) and are more prone to relapse with the same organism (29.2% vs 0%, respectively;  = 0.01) as compared to those with .

Limitations: The result of this small retrospective study involving a single center may not be generalizable to other centers. There is also no data for comparative analysis on other coagulase-negative staphylococci such as , which belongs to the same family as .

Conclusions: Although peritonitis is more virulent with significant morbidity, can cause similarly serious peritonitis. This largest case series of peritonitis enabled better characterization of clinical features and outcomes of patients with peritonitis.