Fungal infection caused by Histoplasma capsulatum
Endemic to the Ohio, Missouri, and Mississippi River valleys in the United States
Exposure from disruption of soil containing organisms leads to aerosolization
Activities associated with high-level exposure include spelunking, excavation, and demolition of old buildings
Infection occurs via inhalation
In immunocompetent patients:
Phagocytes and epithelial cells eventually organize and form granulomas that go on to fibrose and calcify
In immunocompromised patients:
The infection is not contained and can disseminate
Phagocytes and epithelial cells eventually organize and form granulomas that go on to fibrose and calcify
The infection is not contained and can disseminate
Histoplasmosis
Carcinoid Lung Tumors
Toxoplasmosis
Lung Cancer, Small Cell
Aspergillosis
Lymphoma, Mediastinal
Coccidioidomycosis
Mediastinal Cysts