Pulmonary Histoplasmosis Identified by Video-Assisted Thoracic Surgery (VATS) Biopsy: a Case Report

Histoplasmosis is a common endemic mycosis in North, Central, and South America, but Korea is not known as an endemic area. We treated an immunocompetent Korean patient who had histoplasmosis. A 65-year-old Korean man presented with multiple pulmonary clumps of tiny nodules in the both lungs. He had been diagnosed 40 years earlier with pulmonary tuberculosis (TB) and a fungus ball had been diagnosed 4 years earlier. He denied any history of overseas travel. The patient visited our hospital with dyspnea, blood-tinged sputum, and weight loss, which had appeared 2 months earlier. The patient underwent video-assisted thoracic surgery (VATS) lung biopsy. The biopsy sample showed necrotizing granuloma and the presence of multiple small yeast-like fungi. Tissue culture confirmed Histoplasma capsulatum, and he was finally diagnosed with pulmonary histoplasmosis. Therapy was initiated with 200 mg itraconazole orally once per day. The symptoms disappeared 1 week after the start of treatment. After 4 months, low-dose chest computed tomography showed improvement in the ground glass opacity and size of the lung lesions. In conclusion, we report a case of an immunocompetent patient who developed histoplasmosis in Korea. When a patient shows unexplainable progressive infiltrative lung lesions, histoplasmosis should be considered as one of differential diagnoses although Korea is not an endemic area.