title: Microbial substitution of Mycobacterium avium-intracellulare to Mycobacterium abscessus during clinical course.
abstract: Mycobacterium avium-intracellulare (MAI) is, among acid-fast bacilli, the most common cause of nontuberculous pulmonary diseases, and MAI infections are often treated according to the guidelines of the American Thoracic Society. However, despite the use of multiple drugs, patients sometimes do not recover with the initial round of treatment. Other kinds of nontuberculous mycobacteria are sometimes found in patients' respiratory samples, even during such treatment for MAI pulmonary disease. We experienced three patients with pulmonary disease due to Mycobacterium abscessus (MA) in whom the disease was difficult to treat because of resistance to all the antituberculous agents used. MA infection had occurred in these patients after long-term treatment with multiple drugs for previous MAI pulmonary disease. We considered that the MA infection in these patients appeared to be the result of insufficient efficacy of the drugs used for MAI and insufficiently aggressive use of antituberculous agents. It thus appeared that MA infection was the result of microbial substitution, and that, if this is the case, the guidelines for the treatment of MAI may need to be modified to eliminate microbial substitution.
authors.affiliation: Department of Internal Medicine Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan. s2069@nms.ac.jp
authors.forename: Takahito
authors.initials: T
authors.lastname: Nei
authors.forename: Takefumi
authors.initials: T
authors.lastname: Saitoh
authors.forename: Kouzo
authors.initials: K
authors.lastname: Morimoto
authors.forename: Kohichi
authors.initials: K
authors.lastname: Watanabe
authors.forename: Kenji
authors.initials: K
authors.lastname: Hayashihara
authors.forename: Arata
authors.initials: A
authors.lastname: Azuma
authors.forename: Shoji
authors.initials: S
authors.lastname: Kudoh
mesh_terms: D000368:Aged; D000995:Antitubercular Agents / Q000627:therapeutic use; D024901:Drug Resistance, Multiple, Bacterial; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000188:drug therapy / Q000382:microbiology; D008875:Middle Aged; D009161:Mycobacterium / Q000254:growth & development / Q000302:isolation & purification*; D009164:Mycobacterium Infections / Q000188:drug therapy* / Q000382:microbiology; D015269:Mycobacterium avium Complex / Q000254:growth & development / Q000302:isolation & purification*; D015270:Mycobacterium avium-intracellulare Infection / Q000188:drug therapy* / Q000382:microbiology
chemical_list: D000995:Antitubercular Agents