Nontuberculous mycobacterium as a hidden cause of noncystic fibrosis bronchiectasis

Background The incidence of lung colonization and infection owing to nontuberculous mycobacteria (NTM) in patients with cystic fibrosis (CF) and non-CF bronchiectasis is increasing worldwide, which may play a role in pathogensis of bronchiectasis. Aim The aim of this study is to search about NTM as a hidden cause of non-CF bronchiectasis. Patients and methods This is an observational cohort study done at Chest Department of Menoufia University Hospital on 40 patients with non-CF bronchiectasis more than 18 years of age between June 2017 and June 2018. All patients underwent spirometry, chest radiograph, high-resolution computed tomography, and sputum examination for tuberculous and NTM. The sputum samples were assessed by PCR, and positive cases did another PCR after 2 months. Results A total of 40 (21 females and 19 males) patients were included in the study, with mean age of 55.2±6.5 years, mean BMI of 21.4±2.1, and mean height of 163.7±7.3 cm. There were 7.5% of non-CF bronchiectasis cases with NTM (n=3). Mycobacterium avium complex (MAC) was the most common mycobacteria (66.6%) of positive patients. NTM isolation was significantly higher in elderly, tall, low BMI, and female patients (66%). High-resolution computed tomography of patients with NTM especially MAC has shown mucous plugging, peripheral nodules, and ectatic changes in bronchi, and also sputum purulence was less in patients positive for NTM. Conclusion NTM, especially MAC, may be a hidden cause in non-CF bronchiectasis and must be treated properly.