Laboratory and clinical investigation of lysis centrifugation blood culture method for fungemia

We compared the lysis centrifugation blood culture system using Isolator (Du Pont) to the conventional blood culture bottle using BCB system (Roch), and the following results were obtained. In the investigation of experimental fungemia made by human blood and Candida albicans, the organism was detected 9/12 after 1 day and 11/12 after 3 days by Isolator, although the organism was detected 3/12 after 3 days and 11/12 after 6 days by the culture bottle system. In the experimental fungemia of Candida tropicalis, the organism was detected 12/12 after 2 days by Isolator, although it was detected 1/12 after 6 days and 4/12 after 10 days with the culture bottle system. Isolator showed faster and a more sensitive detection rate for fungemia. Clinical investigation of 94 cases (180 cultures) showed a 11.1% isolation rate with Isolator system and a 7.1% isolation rate with the culture bottle system. In 43 cases which were examined by the both systems, 7 cases were positive with Isolator, 3 positive with culture bottle. The culture bottle system isolated only Candida albicans and Candida parapsilosis, where as the Isolator isolated Candida albicans, Candida parapsilosis, Candida tropicalis, Candida krusei, and Candida spp. This investigation suggested that the Isolator system was an excellent method for the detection of fungemia.