Chronic pulmonary histoplasmosis with an oral lesion.

Histoplasmosis is a fungal disease resulting from inhalation of airborne spores of the organism Histoplasma capsulatum. The disease is endemic to the Ohio and Mississippi river valleys. Oral lesions are not common, but when present, they are usually associated with the severe disseminated form of histoplasmosis. This particular case is presented as an example of chronic pulmonary histoplasmosis in which a localized gingival lesion represented the initial clinical manifestation of the disease. Diagnosis was based on a positive biopsy and the results of chest radiographic examination. If, as in this case, serologic, hematologic, and physical examination results are negative, the biopsy of suspicious lesions is of paramount importance to the clinical differential diagnosis.