Problems in management of opportunistic fungal diseases.

Opportunistic fungal infections are now common and will become more common as a consequence of the use of various regimens of immunosuppressive therapy for a variety of diseases and because of AIDS. These infections can be broadly divided into those that take advantage of a neutrophil defect (e.g., candidiasis, aspergillosis, and mucormycosis) and those that take advantage of a T cell mononuclear phagocyte defect (e.g., cryptococcosis, histoplasmosis, and coccidioidomycosis). Problems in diagnosis have been apparent since these infections were first recognized. The usual clinical specimens are often not revealing, and attempts to develop special serologic and biochemical tests have been made for years, but progress has been slow. Problems in treatment stem first from a lack of an early diagnosis and second from a lack of drugs that are effective and relatively nontoxic. It is difficult to evaluate new drugs if we cannot make accurate diagnoses; this difficulty is compounded by the low rate of autopsies in the academic hospitals where such studies are conducted.