Bacterial strains

MAH strain TH135 isolated from the sputum of a seriously ill patient with worsening pulmonary MAH disease at Higashinagoya National Hospital of the National Hospital Organization was used as the reference strain. As reported previously²³, 46 MAH isolates used in genome analysis in this study were provided by nine National Hospital Organization hospitals across Japan. These clinical isolates were obtained from the sputa of 46 patients with distinct clinical courses (see below). Only one strain per patient was analyzed in this study. Of the patients diagnosed with pulmonary MAH disease (corresponding to the diagnostic criteria of the American Thoracic Society and the Infectious Diseases Society of America⁵²) between July 2008 and September 2009, those who started clarithromycin-based multidrug treatment within 18 months, based on decisions made by the corresponding physician-in-charge because of deterioration in the patients’ condition, were classed as the progressive disease group (n = 17). Those who did not receive treatment because their condition was stable were classed as the stable disease group (n = 29). During the observation period, the condition of each patient was evaluated several times a year based on chest radiograph findings (including chest computed tomographic images), clinical symptoms, and/or microbiological findings. Parameters of age, sex, type of pulmonary disease, and the presence of underlying disease were not significantly different between the two groups²³.