Molecular mechanisms of drug resistance in fungi.

Failures of treatment in fungal infections have drawn attention recently to the problem of antifungal resistance and its underlying mechanisms. The number of fungal isolates that are resistant to the orally active azole antifungals, especially fluconazole, is growing. Amphotericin-B-resistant isolates have been recovered during treatment of patients with candidiasis, and resistance to flucytosine is so common that this antifungal is no longer recommended as a single-drug therapy.