Response to fluconazole by 23 patients with human immunodeficiency virus infection and oral candidiasis: Pharmacological and mycological factors

The MICs of fluconazole for strains of Candida species and the levels of fluconazole in serum were determined at day 0 and day 14 for 23 human immunodeficiency virus-infected patients with oral candidiasis who were treated orally with 100 mg of fluconazole per day for 14 days. Among the 23 patients, 11 (48%) were not clinically cured and had persistent isolation of Candida albicans (n = 10) and/or presence of non-C. albicans (n = 6). Clinical response could be predicted by the susceptibility of the strain to fluconazole determined at day 0. All 12 patients who were cured were infected with a strain for which the MIC was < 0.78 mg/liter. All four patients who were infected with a strain for which the MIC was > 3.12 mg/liter experienced clinical failure. These data suggest that a C. albicans strain could be defined as being susceptible when the MIC of fluconazole is < 0.78 mg/liter and as being resistant when the MIC is > 3.12 mg/liter.