Huang HY, Chung FT, Lo CY, et al. - Researchers undertook this longitudinal cohort analysis to define the etiology as well as clinical characteristics of bronchiectasis in Taiwan. They analyzed 15,729 adult patients with newly diagnosed non-cystic fibrosis bronchiectasis from January 2002 to December 2016. The most common etiology was idiopathic (32%), followed by post-pneumonia (24%). Post-tuberculosis (12%), chronic obstructive pulmonary disease (14%), asthma (10%), gastroesophageal reflux disease (2%) and rheumatic diseases (2%) were documented as the other causes. The most common bacteria identified was Pseudomonas aeruginosa (5.3%). A higher sputum isolation rate of non-tuberculosis mycobacteria vs P. aeruginosa was detected in patients with post-tuberculosis. A higher frequency of chronic lung infection was reported in patients with post-tuberculosis and post-pneumonia bronchiectasis vs other groups. Overall, major bronchiectasis causes in Taiwan were: idiopathic, post-infection and tuberculosis. Among separate etiology phenotypes, differences were evident in terms of clinical features and sputum microbiology.