[Three cases of Mycobacterium kansasii pulmonary diseases in previously healthy young women].

Mycobacterium kansasii pulmonary diseases account for 20% of cases of non-tuberculous mycobacteria. Most patients are male. However, a recent study has found that radiological examinations in female patients often reveal nodular, bronchiectatic opacities. We describe 3 young women with cavitary opacities. Patient 1 was a 35-year-old woman in whom thin-walled cavitary opacities were detected in the upper lobe during a routine checkup. Sputum examination and fiberoptic bronchoscopy led to a diagnosis of M. kansasii pulmonary disease. Patient 2 was a 23-year-old woman who presented with hemoptysis. Thin-walled cavitary opacities were detected in the right upper lobe. Infection with M. kansasii was diagnosed after a sputum examination. Patient 3 was a 43-year-old woman in whom thin-walled cavitary opacities were detected in the left upper lobe during a routine checkup. Infection with M. kansasii was diagnosed after a fiberoptic bronchoscopic examination. Patient 1 was successfully treated with rifampicin, ethambutol, and levofloxacin, and patients 2 and 3 were successfully treated with isoniazid, rifampicin, and ethambutol. The possibility of M. kansasii pulmonary diseases should be considered in a previously healthy young woman with thin-walled cavitary opacities in the upper lobe.