Fungal infections are usually more difficult to treat than bacterial infections, because fungal organisms grow slowly and because fungal infections often occur in tis-sues that are poorly penetrated by antimicrobial agents (e.g., devitalized or avascular tissues). Therapy of fungal infections usually requires prolonged treatment. Poten-tially life-threatening infections caused by dimorphic fungi are becoming more common because increasing numbers of immunocompromised patients are seen in clinical practice; AIDS, organ and bone marrow trans-plantation, and illnesses associated with neutropenia all predispose individuals to invasive fungal infection.
Superficial fungal infections involve cutaneous sur-faces, such as the skin, nails, and hair, and mucous mem-brane surfaces, such as the oropharynx and vagina.
A growing number of topical and systemic agents are available for the treatment of these infections. Deepseated or disseminated fungal infections caused by di-morphic fungi, the yeasts Cryptococcus neoformans, and various Candida spp. respond to a limited number of systemic agents: amphotericin B desoxycholate (a poly-ene), amphotericin B liposomal preparations, flucyto-sine (a pyrimidine antimetabolite), the newer azoles, in-cluding ketoconazole, fluconazole, itraconazole and voriconazole, and capsofungin (an echinocandin).