Objectives: This study was designed to determine the susceptibility profile and in vitro efficacy of amphotericin B (AMB), fluconazole (FLU), and itraconazole (ITRA) against yeasts isolated from blood cultures in Hacettepe University Hospital. Methods: Fungal strains (n=107) isolated from blood cultures within the time period of February 1996 to November 2000 were included in the study. The strains were identified by standard mycological methods. Antifungal susceptibility tests were performed and interpreted in accordance with the microdilution method recommended by NCCLS (M27A). The MIC (µg/ml) results were read after 24 and 48 h of incubation. FLU and ITRA resistance rates of Candida spp. were determined according to the breakpoints proposed by NCCLS. C. krusei isolates were accepted to be FLU-resistant, regardless of their FLU MICs. Results: Candida albicans constituted the most common species, followed by C. tropicalis and C. parapsilosis. Overall, 48 (44.9%) of the isolates were of non-albicans Candida spp. MICs at 48 h were within 2 two-fold dilutions with the 24 h MICs (Table) for most of the isolates. At 24 h, except the FLU-resistant C. krusei, none of the Candida isolates were resistant to FLU or ITRA. Two (C. albicans, C. tropicalis) and 8 (C. albicans, C. tropicalis, C. guilliermondii) of the isolates were susceptible-dose dependent (S-DD) to FLU and ITRA, respectively. Conclusions: 1. Non-albicans Candida spp. are a significant cause of fungemia in our hospital. 2. AMB MICs are scattered in a narrow range, incapacitating the discrimination of resistant isolates. 3. Except for FLU- resistant C. krusei, resistance to FLU or ITRA is not observed among our Candida isolates. However, S-DD isolates are rare but likely and should be of concern in cases with unexpected clinical failure with regular doses.
Full conference title:
11th European Congress of Clinical Microbiology and Infectious Diseases
- ECCMID 11th (2001)