EMERGING FUNGAL PATHOGENS IN IMMUNOCOMPROMISED PATIENTS - CLASSIFICATION, DIAGNOSIS, AND MANAGEMENT

Fungi such as Fusarium species, Trichosporon species, Curvularia speci es, and Alternaria species previously were thought to represent contam ination or harmless colonization when isolated from immunocompromised patients. More recently, the pathogenic role of these and other fungi has been clearly established. Three diverse groups of fungi are respon sible for these emerging infections: the agents of phaeohyphomycosis a nd hyalohyphomycosis and certain yeasts. Reports of the emergence of t hese organisms as significant pathogens may be ascribed to increasing awareness by physicians and microbiologists, aggressive culture of pat ient specimens, increasingly cytotoxic chemotherapy, and selection of resistant organisms by the widespread empirical use of amphotericin B. Infections with these fungi tend to be disseminated and are frequentl y fatal in immunocompromised hosts. Treatment of these infections is n ot standardized. Experimental therapy in murine models of fungal infec tions suggests a role for newer agents, combination antifungal chemoth erapy, and immunotherapy.