Diffuse pulmonary histoplasmosis

Chest radiograph shows diffuse reticulonodular infiltrates involving all lung fields in a patient who experienced extensive exposure to Histoplasma capsulatum spores during removal of bird droppings from a bell tower. This patient exhibited dyspnea and hypoxia. Diagnosis was based on detection of high concentrations of antigen in urine, bronchoalveolar lavage fluid, and blood. The patient improved rapidly in response to glucocorticoids and amphotericin B.