In vitro susceptibilities of Candida and Cryptococcus neoformans isolates from blood cultures of neutropenic patients.

Fluconazole-resistant Candida albicans and intrinsically fluconazole-resistant Candida species have been reported as bloodstream isolates. However, an association between the isolation of fluconazole-resistant Candida from the bloodstream and patient risk factors for fungemia has not been established. The purpose of this study was to determine the prevalence of fluconazole resistance in bloodstream isolates of Candida species and Cryptococcus neoformans collected from patients with neutropenia, one of the most important risk factors for fungemia. MICs of voriconazole, fluconazole, itraconazole, ketoconazole, amphotericin B, and flucytosine were determined by the National Committee for Clinical Laboratory Standards M27-A method (1997). Voriconazole, on a per-weight basis, was the most active azole tested. Fluconazole resistance (MIC >/= 64 microg/ml) was not identified in any of the C. albicans (n = 513), Candida parapsilosis (n = 78), Candida tropicalis (n = 62), or C. neoformans (n = 38) isolates tested.