Impact of concomitant nontuberculous mycobacteria and Pseudomonas aeruginosa isolates in non-cystic fibrosis bronchiectasis Meng-Heng Hsieh,1,2,* Chun-Yu Lin,1–3,* Chen-Yu Wang,2 Yueh-Fu Fang,1–3 Yu-Lun Lo,1,2 Shu-Min Lin,1,2 Horng-Chyuan Lin1,2 1Department of Thoracic Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; 2Department of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan; 3Department of Pulmonary and Critical Care, Saint Paul’s Hospital, Taoyuan, Taiwan *These authors contributed equally to this work Purpose: Pseudomonas aeruginosa is associated with pulmonary function decline and high disease severity in non-cystic fibrosis (CF) bronchiectasis. The prevalence of nontuberculous mycobacteria (NTM) in non-CF bronchiectasis patients has increased recently. This study investigated the impact of NTM with or without P. aeruginosa isolates in non-CF bronchiectasis patients.Patients and methods: Our retrospective study included 96 non-CF bronchiectasis patients from January 2005 to December 2014. We recorded the presentation, exacerbations, emergency department (ED) visits, hospitalization, serial pulmonary function, radiologic studies, and sputum culture results. All patients were followed up for at least 2 years.Results: The 96 patients were divided into four groups: patients with concomitant negative NTM and P. aeruginosa isolates (n