Current experience using blood culture bottles to identify causative organisms of endophthalmitis

Abstract

Abstract: : Purpose: To investigate the usefulness of blood culture bottles in isolating the causative organisms of endophthalmitis Methods: A retrospective, non–comparative, case series of surgical isolates from a single institution between January 2000 and July 2003. These specimens were processed immediately after the clinical procedure using two techniques: blood culture bottle (BCB) and filter paper placed on culture plates (FP). Results: The study included 48 specimens from 48 patients in eyes with either clinically suspect endophthalmitis or open globe injuries. Positive culture results were obtained in 33 of 48 isolates. Culture positivity rates were 63% in the BCB group and 69% in the FP group. The sensitivity rate of the blood culture bottle was 91% when compared to the filter paper method. Overall, the BCB method identified gram–positive, gram–negative, and fungal organisms. Organisms recovered by the FP method but not by the BCB were Staphylococcus aureus (1), Moraxella (1), and Enterococcus species (1). Conclusions: The rates of achieving a positive culture from endophthalmitis specimens is similar in both methods of testing. Even though the results with the FP method were better, the current study shows the rates were similar with both techniques. The advantage of BCB is that it is a simple and useful alternative when microbiology staff is unavailable for processing.

Keywords: endophthalmitis • microbial pathogenesis: clinical studies • clinical laboratory testing