The disease caused by Histoplasma spp., histoplasmosis, may be asymptomatic and diagnosed incidentally as a "coin lesion" on chest X-ray. It has the potential to cause acute or chronic pulmonary infection. This can occur in workers exposed to a large inoculum in construction or cave excavation. H. duboisii causes the disease African histoplasmosis, which involves skin and bones and rarely the lungs.
The immunocompromised are at risk for disseminated histoplasmosis following pulmonary infection. Disseminated infection may lead to oropharyngeal ulcers, hepatic and/or splenic involvement, or infection of the bone marrow, CNS, major arteries, or cardiac valves.
Diagnosis of disseminated histoplasmosis can be made with an antigen test performed on urine or serum.
