Fungal infections

Over the last decade, there have been changes in the epidemiology of fungal infections as well as dramatic improvements in the antifungal armamentarium. Candida species are an increasingly important cause of infection among patients in intensive care units. Mold infections continue to occur predominantly among highly immunosuppressed patients, such as those who have acute leukemia and those undergoing hematopoietic stem cell or solid organ transplantation. Aspergillus species remain the most common molds to cause invasive infection, but other environmental molds, such as Scedosporium, Fusarium, and various zygomycetes, including Rhizopus and Mucor, appear to be increasing in some medical centers. We now have available a new class of antifungal agents, the echinocandins, that act to damage the cell walls of Candida and Aspergillus species. Although limited in spectrum and only available in intravenous formulations, these agents are very safe and extremely well tolerated. Another new agent is the expanded spectrum triazole voriconazole. This agent has a very broad spectrum of activity, is available in both oral and intravenous formulations, and is approved for treatment of aspergillosis, other molds, and candidiasis. The major drawbacks with voriconazole are the number of drug-drug interactions and side effects, including rash, hepatitis, and visual disturbances. Treatment with amphotericin B, long the mainstay of antifungal therapy despite its inherent toxicity, is required much less often since the introduction of these new antifungal agents.