Alterations of gut microbiota in patients with active pulmonary tuberculosis in China: a pilot study.

BACKGROUND The aim of this study was to identify the differences in diversity, composition, and function of the gut microbiota between tuberculosis (TB) patients and healthy controls (HCs). METHODS A cross-sectional study was conducted in three cities of China. Stool samples from 94 treatment-naive TB patients and 62 HCs were analyzed by 16S rRNA gene sequencing. TB patients were further divided into antibiotic-free and antibiotic-exposure according to their use of non-specific antibiotics before the TB diagnosis. RESULTS Compared with HCs, antibiotic-free TB patients presented a different gut microbial community (P < 0.005) and decreased Shannon diversity (P < 0.005). Among TB patients, the relative abundances of short-chain fatty acid (SCFA)-producing genera such as Lachnospiraceae ND3007 group (log2(FC) = -2.74) were lower, while several conditional pathogen-related genera such as Enterococcus (log2(FC) = 12.05) and Rothia (log2(FC) = 6.322) were at higher levels. In addition, 41% of patients received antibiotics before TB diagnosis. Antibiotic exposure was correlated with an additional reduction in α diversity and depletion of SCFA-producing bacteria. Microbial functional analysis revealed that the biosynthesis capacity of amino acids and fatty acids was lower among TB patients compared to HCs. CONCLUSIONS Significant alterations in gut microbiota composition and metabolic pathways of TB patients were observed. Antibiotic exposure could alter the gut microbiota of TB patients, which should be considered in anti-TB treatment.