Histoplasmosis: a masquerader of sarcoidosis.

Although endemic along the Ohio and Mississippi River valleys in the United States, histoplasmosis may occur in many parts of the world. The multisystem involvement, the presence of non-caseating granulomas, and an elevated angiotensin converting enzyme in histoplasmosis cause diagnostic confusion with sarcoidosis. A careful epidemiologic history, serological tests, and tissue cultures are helpful in establishing the correct diagnosis.