Time to positive culture and identification for Candida blood stream infections

Abstract

Candidemia and delay to appropriate therapy contribute to increased morbidity and mortality. Current literature addresses the delay between blood culture collection and final identification; however, it fails to delineate differences among species. The purpose of this study was to quantify the time to yeast detection and identification relative to blood culture collection and determine whether differences exist among species. In this retrospective study, all cases of Candida isolation for 2 years were reviewed. The time delays between blood culture and detection of Candida growth were quantified as well as the additional time required for final species identification. Initiation of antifungal therapy was assessed in relation to culture collection, detection of yeast, and final identification. The appropriateness of therapy at each time point was also analyzed. Most Candida infections were caused by either Candida albicans (n = 43) or Candida glabrata (n = 27). Mean time to positive yeast detection for C. albicans was 35.3 +/- 18.1 h, whereas that of C. glabrata was 80.0 +/- 22.4 h (P < 0.0001). Mean time to final identification for C. albicans was 85.8 +/- 30.9, whereas that of C. glabrata was 154 +/- 43.8 h (P < 0.0001). Mean time to appropriate therapy for C. albicans isolates was 43.3 +/- 27.6 h compared with 98.1 +/- 38.3 h (P < 0.0001) for C. glabrata isolates. The time delay between blood culture collection and yeast detection as well as final identification was significantly longer for C. glabrata isolates when compared with C. albicans. As a result, mean time to appropriate antifungal therapy was significantly longer in patients with C. glabrata isolates.