Correlation between antifungal susceptibility testing of Candida isolates from patients with HIV infection and clinical results after treatment with fluconazole

Abstract

In an open-label controlled study 23 HIV-infected patients (CDC IV A-E) with documented oropharyngeal candidosis were treated with 100 mg fluconazole orally over 5 days (53 episodes; 1-6 treatments/patient). Efficacy data were compared with a control group of 21 patients who received treatment for 10-21 days with 100 mg fluconazole for candidosis. Candida isolates were repeatedly recovered from patients before and after treatment with fluconazole and antifungal susceptibility testing (microbroth-dilution) was done. Inoculum size, medium pH, incubation time and temperature were standardized. Up to 85% of patients responded to therapy clinically and mycologically. Candida albicans was the most important yeast (86%) isolated from cultures of oral washings. In 90% of C. albicans isolates MIC to fluconazole were low (< or = 1.56 mg/l). Primary resistance to fluconazole was not seen, but secondary resistance occurred in two cases clinically and in vitro (MIC > or = 25 mg/l). Short treatment for 5 days was as successful as for 10 to 21 days without leading to significantly more recurrences of oral candidosis in these patients. Selection of Candida spp. other than C. albicans (e.g. Candida krusei, Torulopsis glabrata) under repeated fluconazole treatment occurred rarely. One patient developed clinical signs of chronic recurrent candidiasis, where only C. krusei could be cultured repeatedly.