Comparison of the BACTEC Blood Culture and Conventional Culture Methods for Isolation of Microorganisms Causing Peritonitis in CAPD Patients

Ahn, Sung Min; Jung, Min Young; Choi, Hyeok Soo; Choi, Bo Youn; Kim, Su Sun; Seo, Seung In; Kim, Min Gang; Kim, Soo Jin; Oh, Ji Eun

Abstract

BACKGROUND/AIMS
Peritonitis is the most frequent complication of continuous ambulatory peritoneal dialysis (CAPD). Prompt recognition and treatment of peritonitis is important. The purpose of this study was to compare the effectiveness of isolation of the microorganisms causing CAPD peritonitis by the BACTEC blood culture and conventional methods.
METHODS
We retrospectively reviewed 38 episodes of peritonitis in 34 CAPD patients between September 2007 and February 2010. Two methods of processing dialysate from patients on CAPD were used. Blood culture was performed using two 10-mL effluents, which were inoculated into a pair of BACTEC culture bottles. The conventional method was performed using 50 mL of centrifuged dialysate. The sedimented dialysate was inoculated onto blood agar and MacConkey agar plates or into thioglycollate broth. To evaluate effectiveness, we compared the rate of positive culture results and the time to identify the causative organism of the two culture methods.
RESULTS
Use of the BACTEC bottle method resulted in more positive culture results than did conventional culture (86.8 vs. 57.9% p = 0.003). The time taken to identify the causative organism from culture-positive peritonitis was more rapid using the blood culture compared with the conventional culture method (90 vs. 109 hr, p = 0.03).
CONCLUSIONS
Blood culture using the BACTEC bottle is more effective than the conventional culture technique for detection of causative microorganisms in CAPD peritonitis.