A case of pulmonary histoplasmosis diagnosed after lung lobectomy

Histoplasmosis is considered a fairly rare imported mycosis in Japan. Here we report a case of histoplasmosis describing the preoperative findings, histopathological findings, supposed infection route, and appropriate treatment, including the postoperative management. A healthy 65-year-old man was found at routine medical check-up to have an abnormal opacity on chest radiography. A chest computed tomography (CT) scan showed a nodular lesion in the posterior basal segment of the right lung, as well as two smaller nodules in the same lobe. This was highly suggestive of primary lung cancer with pulmonary metastases in the same lobe. We thus performed a right lower lobectomy with hilar and mediastinal lymph node dissection via thoracotomy. The lesions were diagnosed as pulmonary histoplasmosis on histopathology. At 6-month follow-up examination, the patient was free from fungal infection without any postoperative medication. We describe a patient with pulmonary histoplasmosis diagnosed following surgical lobectomy. The possibility of pulmonary histoplasmosis should be considered in the differential diagnosis of pulmonary nodular lesions.