Disseminated hyalohyphomycosis caused by a novel human pathogen, Fusarium napiforme.

Fusarium species are saprophytic molds and important plant pathogens, although they are increasingly recognized as agents of human mycosis. Frequently, the infection is superficial. Deep tissue infection may occur as an opportunistic hyalohyphomycosis, and wide dissemination is common in immunocompromised hosts. We describe a novel case of disseminated hyalohyphomycosis caused by F. napiforme in a patient with acute myelogenous leukemia. The clinical manifestations of this infection were similar to those attributed to infection with other species. In vitro susceptibility testing demonstrated resistance to amphotericin B and flucytosine, and progressive infection was documented until recovery of granulocyte function. The distinguishing clinical mycologic characteristics of this opportunistic mold are the unique turnip- or lemon-shaped microconidia. F. napiforme is a new agent of hyalohyphomycosis, further emphasizing the importance of Fusarium species as opportunistic molds.