The saprophytic mold form occurs naturally in acidic, organic soil around waterways and beaver dams. Spores are inhaled. There is no person to person spread. Lymphogranulomatous spread occurs regularly but calcification and caseation do not occur like histoplasmosis.
Most patients develop no symptoms or a mild pneumonia and recover completely.
Fever, chills and purulent sputum not responsive to TB therapy is suggestive. Extrapulmonary spread occurs to bone or skin. May look like a pseudoepithelioma. Skin disease - always means dissemination.