Outcomes of corynebacterium peritonitis: a multicenter registry analysis

Abstract

Background: Corynebacterium is a rare cause of peritonitis that is increasingly being recognized in peritoneal dialysis (PD) patients. The aims of this study were to compare Corynebacterium peritonitis outcomes with those of peritonitis caused by other organisms and to examine the effects of type and duration of antibiotic therapy on outcomes of Corynebacterium peritonitis. Methods: Using Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) data, we included all PD patients who developed peritonitis in Australia between 2004 and 2014. The primary outcome was peritonitis cure by antibiotic therapy, defined as resolution of a peritonitis episode with antibiotics alone and without being complicated by recurrence, relapse, catheter removal, hemodialysis transfer, or death. Peritonitis outcomes were analyzed using multivariable logistic regression. Results: A total of 11,122 episodes of peritonitis in 5,367 patients were included. Of these, 162 episodes (1.5%) were due to Corynebacterium. Compared with Corynebacterium peritonitis, the odds of cure were lower in peritonitis due to Staphylococcus aureus (odds ratio [OR] 0.66, 95% confidence interval [CI] 0.45 – 0.97), Pseudomonas (OR 0.22, 95% CI 0.14 – 0.33), other gram-negative organisms (OR 0.52, 95% CI 0.35 – 0.75), fungi (OR 0.02, 95% CI 0.01 – 0.03), polymicrobial organisms (OR 0.32, 95% CI 0.22 – 0.47), and other organisms (OR 0.66, 95% CI 0.44 – 0.99) but similar for culture-negative and other gram-positive peritonitis. Similar results were observed for hemodialysis transfer and death. The outcomes of Corynebacterium peritonitis were not associated with the type of initial antibiotic selected (vancomycin vs cefazolin) or the duration of antibiotic therapy (≤ 14 days vs > 14 days). Conclusions: Outcomes for Corynebacterium peritonitis are generally favorable compared with other forms of peritonitis. Cure rates did not appear to differ if peritonitis was treated initially with vancomycin or cefazolin or if treatment duration was prolonged beyond 14 days.