Epidemiology of culture isolates from peritoneal dialysis peritonitis patients in southern India using an automated blood culture system to culture peritoneal dialysate

Aim: Continuous ambulatory peritoneal dialysis (CAPD) is a major form of therapy for chronic end stage renal disease patients, which may lead to CAPD-associated peritonitis. The spectrum of organisms associated with CAPD peritonitis varies geographically. Not much data is available regarding this from southern India. The aim of this study was to characterize the spectrum of organisms associated with CAPD peritonitis in this region and observe the utility of automated blood culture systems to culture peritoneal dialysate. Methods: Ninety episodes of peritonitis were cultured over a span of 3 years using an automated blood culture system. Results: The yield of culture positivity was 50%. The most predominant organism was found to be coagulase-negative Staphylococcus spp. (21.1%) followed by Enterobacteriaceae (12.2%). Other organisms isolated were non-fermenting Gram-negative bacilli (4.4%), Pseudomonas aeruginosa (3.3%), alpha-haemolytic Streptococci (3.3%), Candida spp. (2.2%), Staphylococcus aureus (1.1%), beta-haemolytic Streptococci (1.1%) and Micrococci (1.1%). A high degree of resistance to third generation cephalosporins (66.7%) was noted amongst the Gram-negative bacilli. Also, all the Gram-negative bacilli isolated from patients who had prior empirical antibiotic therapy of ceftazidime before arrival at the centre, were resistant to third generation cephalosporins. Conclusion: A varied spectrum of organisms isolated from peritoneal dialysate compared to the global scenario was observed. Also, a high degree of third generation cephalosporin resistance was noted amongst the Gram-negative bacilli. Thus, it is suggested that the empirical therapy should be dependent on the local epidemiology.