Role of the concentration process in the recovery of Candida albicans from blood

Abstract

The lysis-centrifugation system (Isolator TM) is recognized as the standard method for recovery of Candida spp. from blood. In this study, the effect of the concentration process of this system was compared with conventional methods of blood culture using liquid and biphasic media. The tests were performed in vitro using Candida albicans in counts of 100, 10, 1, and 0.5 cells/ml of blood. Cultures onto chocolate agar were performed with the sediment obtained after centrifugation of IsolatorTM tube and with liquid and biphasic media after their incubation for 24 h at 35oC. Gram stain prepared from the conventional methods were also evaluated in the first 24 h. It was possible to detect Candida albicans in blood, regardless both the number of cells or methodology. As blastoconidia were observed in Gram stains at the same time that growth was noted, time for diagnosis was also not different for the compared methods. Therefore, we suggest that the process of concentration is not the single important factor responsible for the recovery rates of Candida albicans from blood by the IsolatorTM system.