Kamata H, et al. - This cross-sectional study was implemented to assess health-related quality of life (HRQL) and determine the influence of chronic Pseudomonas aeruginosa (PA) infection in Mycobacterium avium complex lung disease (MACLD) patients. Impaired HRQL, as indicated by significantly higher St. George’s Respiratory Questionnaire (SGRQ) scores, was noted in MACLD patients with chronic PA infection. A significant association of chronic PA infection with the severity of bronchiectasis was reported in this work.