[Pulmonary mycobacteriosis caused by Mycobacterium peregrinum in a young, healthy man].

A 24-year-old male never-smoker with no contributory medical history was referred to our division because of chronic productive cough and fever. His chest CT showed pulmonary consolidation including nodular shadows around the bronchovascular bundle in both upper lobes and right middle lobe. Sputum smears were negative but cultures were positive for Mycobacterium peregrinum, twice. He was given a diagnosis of pulmonary mycobacteriosis caused by M. peregrinum and treated with clarithromycin, levofloxacin, and ethambutol. His symptoms and the infiltrates improved, and further sputum cultures were negative for mycobacteria. M. peregrinum is a species included in the M. fortuitum group, of rapidly-growing non-tuberculous mycobacteria. To the best of our knowledge, only 2 cases with lung infection caused by M. peregrinum have been previously reported, both of which occurred in patients in their 60s with underlying diseases, including low immunity due to immunosuppressants for polymyositis, or bronchiectasia. We describe a rare case of pulmonary mycobacteriosis due to M. peregrinum in a healthy man without any underlying diseases.