In Vitro Studies of Ketoconazole in Combination with the 5-Fluorocytosine and Amphotericin B against Candida sp. Isolated from Clinical Specimens

임상가검물에서 분리한 Candida sp.의 항진균제 Ketoconazole, 5-Fluorocytosine 및 Amphotericin B의 단독 혹은 복합처리에 의한 항진균력에 대한 연구

The antifungal activities of amphotericin B, 5-fluorocytosine, and ketoconazole in combination of amphotericin B/ketoconazole and 5-fluorocytosine/ketoconazole were determined against 42 strains of Candida spp. isolated from oral cavity. Among 42 strains of Candida species, 36 strains of Candida albicans, 2 strains of Candida parapsilosis and Candida tropicalis 1 strain of Candida krusei and Candida stellatoidea were identified. The minimum inhibitory concentrations(MICs) of amphotericin B, 5-fluorocytosine and ketoconazole for these strains were ranged from 0.05-1.56 mcg/ml, 12.5->100.0 mcg/ml and 0.2-50.0 mcg/ml. In all of the experimental strains, amphotericin B had the greatest antifungal activity on a dilution basis. When a microtiter checkerboard technique was used 5-fluorocytosine acted synergistically with ketoconazole against all strains, whereas amphotericin B has a reduced effect. The killing curve experiments with on strain of Candida albicans WMC-85024 demonstrated that the combination of amphotericin B/ketoconazole and 5-fluorocytosine/ketoconazole produced a decrease in number of colony forming unit of >3 logs in 72 hours.