Disseminated histoplasmosis in patients infected with human immunodeficiency virus.

Progressive disseminated histoplasmosis (PDH) is a common opportunistic infection complicating the course of infection with human immunodeficiency virus (HIV). PDH has been noted in areas nonendemic for histoplasmosis and occurs more frequently in areas heavily endemic for the fungus. PDH is frequently the AIDS-defining illness and presents as a febrile and wasting disease. The respiratory component may be overshadowed by the severity of the systemic illness. Chest roentgenograms show diffuse reticulonodular infiltrates. Frequently, the initial chest roentgenogram may show no abnormalities. Timely diagnosis requires a high index of diagnostic suspicion. Blood cultures, with use of the lysis-centrifugation system, are highly useful, as is the examination of the bone marrow, the peripheral blood smear, and the respiratory secretions. An experimental serological test that detects histoplasma polysaccharide antigen appears to be the simplest diagnostic test. Amphotericin B is the drug of choice for initial therapy, followed by further administration of amphotericin B for suppression. Early results with itraconazole are encouraging for long-term suppression.