Evaluation of Automated Blood Culture System for Body Fluids Culture Other Than Blood

Abstract

Background: We investigated whether culture using an automated blood culture system enhances the recovery of bacteria and fungi from body fluids other than blood when compared to conventional solid media culture methods. Methods: A total of 734 specimens [ascites (n=457), bile (n=5), CAPD (n=28), CSF (n=32), joint fluids (n= 165), pericardial fluid (n=17), and pleural fluid (n=30)] were included in the study. Half of the volume of each specimen was inoculated directly into automated blood culture bottles (bioMeriux, Marcy-I’Etoile, France). The remaining volume was inoculated onto conventional solid media (sheep blood agar, chocolate agar, and phenylethyl alcohol agar) after centrifuging at 3,000 rpm for 10 min. Results: Clinically significant microorganisms were isolated from 62 specimens (8.5%) by automated blood culture and 61 specimens (8.3%) by the conventional solid media culture (kappa index: 0.81, 95% confidence interval: 0.75∼0.89). Contamination was observed in 11 (1.8%) of the automated blood culture specimens and 3 (0.4%) of the solid media culture specimens. The mean turnaround times of the automated blood cultures and the conventional solid media cultures were 3.7 and 2.8 days, respectively (P< 0.0001). Conclusion: Compared with conventional culture methods, no improvement in the recovery of clinically significant microorganisms was noted with the use of the automated blood culture system for the culture of body fluids other than blood. (Korean J Clin Microbiol 2011;14:13-17)