[A case of pulmonary infection due to Mycobacterium simiae].

A 61-year-old woman presented to our hospital with a chronic cough. She had been diagnosed with pulmonary infection due to non-tuberculous mycobacteria by her previous doctor and had received antimycobacterial chemotherapy for 1 year. Chest radiography and computed tomography on the first visit to our hospital revealed nodular shadows with a cavity in the right upper lung field and infiltrative shadows with bronchiectasis in the lingular segment. Mycobacterium simiae was identified using DNA hybridization methods. Analysis of base sequences from sputum samples using 16S rRNA confirmed the identity of all tested isolates as Mycobacterium simiae, and the organism was isolated repeatedly from sputum mycobacterial tests. Pulmonary infection due to Mycobacterium simiae was diagnosed. Rifampicin, Ethambutol and Clarithromycin were administered to the patient, but clinical symptoms have continued, and findings on chest radiography have deteriorated. Cases of pulmonary infection due to Mycobacterium simiae are rare, and this represents the first such case reported in Japan.