The impact of anti-tuberculosis treatment on respiratory tract microbiome in pulmonary tuberculosis

The growing evidence has underscored the significance of interactions between the host and microbiota in respiratory health, presenting a novel perspective on disease management. Yet, comprehension of the respiratory microbiome shifts before and after anti-tuberculosis treatment is limited. This study compares respiratory microbiome profiles in untreated tuberculosis (UTB) and completed TB treatment (CTB) cases with healthy controls, using 16S rRNA sequencing on sputum samples. Significant reduction in sputum microbial alpha diversity was observed in both TB groups when compared to healthy controls (P < 0.05). Beta diversity analysis showed distinct clustering (P < 0.05). Linear discriminant analysis revealed an abundance of potentially pathogenic bacterial genera like Haemophilus, Pseudomonas, and Mycobacterium in the UTB group, while Streptococcus, Rothia, and Neisseria dominated in CTB samples. Healthy sputum microbiomes were enriched with Prevotella, Fusobacterium, Porphyromonadaceae_unclassified, and Peptostreptococcus. Moreover, predicted bacterial functional pathways showed significant differences among the three groups, mainly related to nutrient metabolism. These findings indicated significant microbial dysbiosis in sputum samples recovered from patients with pulmonary TB with an elevated presence of potentially pathogenic bacteria, depletion of beneficial genera, and downregulation of several essential metabolic pathways. Further exploration of respiratory microbiome-based diagnostic biomarkers and their role in targeted treatment strategies in tuberculosis is warranted.