[Comparison of clinical manifestations between Mycobacterium avium-intracellulare complex and Mycobacterium abscessus pulmonary diseases].

OBJECTIVE: To compare the clinical manifestations of nontuberculous mycobacterial (NTM) pulmonary diseases caused by Mycobacterium avium-intracellulare complex (MAC) and Mycobacterium abscessus. METHODS: The clinical manifestations of 18 patients with MAC and 9 patients with Mycobacterium abscessus pulmonary diseases diagnosed from 2010 to 2011 were reviewed. RESULTS: There were no significant differences in the gender, age, body mass index, predisposed diseases, symptoms and positive sputum acid-fast bacillus between MAC and Mycobacterium abscessus groups. Upper lobe cavities were more frequently observed in the MAC group (13/18), whereas nodular bronchiectatic changes were more frequent in the Mycobacterium abscessus group (3/9). Compared with MAC pulmonary diseases, several imaging characteristics were more common in the Mycobacterium abscessus group, including bilateral micro nodules (Mycobacterium abscessus group 8/9 vs MAC group 7/18), tree-in-bud sign (Mycobacterium abscessus group 7/9 vs MAC group 6/18) and multiple bronchiectasis (Mycobacterium abscessus group 8/9 vs MAC group 5/18). CONCLUSIONS: There was considerable overlap in clinical characteristics of MAC and Mycobacterium abscessus pulmonary diseases. However, bilateral micro nodules, tree-in-bud sign and multiple bronchiectasis were more frequently seen in Mycobacterium abscessus than in MAC pulmonary diseases, while upper lobe cavities were more frequently seen in MAC than in Mycobacterium abscessus pulmonary diseases.