Colonic histoplasmosis: a difficult diagnostic problem.

Abstract

Histoplasmosis is caused by inhaling the microconidia (spores) formed by the environmental mold Histoplasma capsulatum, an organism endemic to the Ohio and Mississippi River Valleys in the United States. Histoplasmosis is the most common endemic fungal disease in both normal and immunocompromised hosts; several hundred thousand people are infected with H. capsulatum yearly. Healthy hosts, unless they inhale a large number of conidia, remain asymptomatic or have only mild pulmonary symptoms when exposed to H. capsulatum.