# Gut microbiota profile in newly diagnosed pulmonary tuberculosis patients: an exploratory pilot study in southern India

## TL;DR

This study explores gut microbiota changes in newly diagnosed tuberculosis patients in southern India and finds reduced diversity that worsens with treatment.

## Contribution

The first study from southern India characterizing gut microbiota in pulmonary tuberculosis using 16S sequencing and evaluating probiotic effects.

## Key findings

- PTB patients showed significantly reduced gut microbial diversity compared to healthy controls.
- Antitubercular therapy further depleted gut microbial diversity.
- Probiotic supplementation partially improved microbial richness but did not fully restore diversity.

## Abstract

Emerging evidence suggests the link between pulmonary tuberculosis (PTB) and gut microbiota dysbiosis. This is the first study from the southern Indian population that characterized the gut microbiota of PTB patients using 16 S amplicon sequencing. The analysis revealed a significant reduction in gut microbial diversity among PTB patients, with particularly lower alpha diversity (Chao1 index, p ≤ 0.0001) than healthy controls (HC). This was further depleted during antitubercular therapy (ATT). Beta diversity indicated distinct clustering in all the groups (p < 0.05). Subgroup analyses showed that supplementation of probiotics with ATT improved microbial richness and diversity. However, broader shifts in composition were not observed. At the genus level, specific taxa were upregulated or downregulated in PTB patients compared to HC. Functional analysis showed a depletion in biosynthesis pathways in PTB patients. Short-term probiotic supplementation had a partial effect on microbial recovery but did not fully restore gut microbial diversity. These findings highlight persistent dysbiosis in PTB patients, even after ATT. Large-scale studies are needed to evaluate the role of microbiome-targeted therapies to address this dysbiosis.

The online version contains supplementary material available at 10.1186/s13099-025-00736-x.