Lung cavities in tuberculosis linked to microbial imbalance, study finds

Patients with cavitary pulmonary tuberculosis carry a distinctly altered lung microbiome, marked by an overabundance of Mycobacterium tuberculosis complex and a loss of microbial diversity, according to a retrospective study published in Annals of Clinical Microbiology and Antimicrobials. The findings are associations only; the cross-sectional design of the study rules out any conclusion about cause and effect.

Tuberculosis remains a major global health threat, and the cavitary form of pulmonary disease is associated with more severe manifestations and more complex clinical management. The researchers set out to analyze the pulmonary microbiome in cavitary pulmonary tuberculosis and to explore its associations with clinical indicators.

The team conducted a retrospective study of 200 pulmonary tuberculosis patients who underwent bronchoalveolar lavage fluid metagenomic next-generation sequencing between January 2021 and December 2023. After applying inclusion and exclusion criteria, 189 patients were enrolled and categorized into cavitary and non-cavitary groups based on imaging findings, with 30 patients in the cavitary group and 159 in the non-cavitary group. Differences in clinical characteristics and pulmonary microbiome profiles between the two groups were then analyzed.

Imaging comparisons showed that patients with cavitary pulmonary tuberculosis had a higher proportion of bilateral lung involvement than non-cavitary patients, at 80 percent versus 56.60 percent, a difference that reached statistical significance with a P value of 0.024.

Metagenomic next-generation sequencing demonstrated superior detection performance for Mycobacterium tuberculosis complex compared with conventional methods, according to the study.

The central microbiome finding was that cavitary pulmonary tuberculosis patients exhibited significantly higher abundance of Mycobacterium tuberculosis complex alongside reduced microbial diversity.

To link microbial features with clinical indicators, the researchers used Spearman correlation analysis with false discovery rate adjustment, a statistical method that accounts for multiple comparisons. In this analysis, the presence of cavities was significantly positively correlated with two microbial taxa identified by Linear Discriminant Analysis Effect Size analysis: Mycobacterium tuberculosis complex and Prevotella jejuni.

The authors concluded that cavitary formation in pulmonary tuberculosis is associated with distinct alterations in pulmonary microbiome composition, characterized by increased dominance of Mycobacterium tuberculosis complex and reduced microbial diversity. They noted that specific microbiome features are significantly correlated with key clinical indicators, highlighting their potential value in disease assessment and management. The study explicitly states that all relationships reported are associations and that the cross-sectional design precludes any inference of causality.

The study was published as open access research on 13 October 2026, with Dan Lei, Xiaojing Zhang, Yafeng Zheng, Wei Gai and Shugen Wu listed among the authors.

Subject of Research: Pulmonary microbiome features and their clinical associations in cavitary pulmonary tuberculosis

Article Title: Microbiome features and their clinical associations in cavitary pulmonary tuberculosis

Article References: Lei, D., Zhang, X., Zheng, Y., Gai, W., & Wu, S. (2026). Microbiome features and their clinical associations in cavitary pulmonary tuberculosis. Annals of Clinical Microbiology and Antimicrobials. https://doi.org/10.1186/s12941-026-00889-w

Image Credits: AI Generated

DOI: 10.1186/s12941-026-00889-w

Keywords: tuberculosis, pulmonary microbiome, cavitary pulmonary tuberculosis, metagenomic next-generation sequencing, Mycobacterium tuberculosis complex, microbial diversity, bronchoalveolar lavage fluid, Prevotella jejuni, Spearman correlation, retrospective study, Microbiome, features