The Difference Of Airway Microbiota Between Nontuberculous Mycobacteria Lung Disease And Bronchiectasis

Background: The role of airway microbiota in pathogenesis of nontuberculous mycobacteria lung disease (NTM-LD) is unclear. Methods: We enrolled patients with NTM-LD or bronchiectasis. Broncho-alveolar lavage fluid (BALF) was collected while routine bronchoscopy and its microbiome data was analyzed. Results: For the enrolled NTM-LD patients and bronchiectasis group, there was no statistical significant difference for age and gender. We analyzed the BALF microbiome and found patients with NTM-LD had similar Shannon and Chao1 index as well as beta diversity without statistically significance in comparing with bronchiectasis controls. We checked top 10 most abundant airway microbiota that revealed an obviously high abundance of Prevotella species in the patients with NTM-LD. In regard to the results from Linear discriminant analysis (LDA) Effect Size (LEfSe), only Pseudomonas and Ruminococcaceae demonstrated LDA score > 3.0 favoring NTM-LD. Conclusions: The preliminary data of airway microbiome in patients with NTM-LD seems similar in alpha and beta diversity in comparing with those with bronchiectasis. It might indicate that the dysbiosis does not exist in airway microbiome of NTM-LD patients. NTM-LD might have more Pseudomonas and Ruminococcaceae in their lower respiratory tract. Further validation is required.