Reduced gut microbiota diversity in ulcerative colitis patients with latent tuberculosis infection during vedolizumab therapy: insights on prophylactic anti-tuberculosis effectsOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This cohort study asked how latent tuberculosis infection (LTBI) and preventive anti-tuberculosis drugs affect the gut microbiota in ulcerative colitis (UC) patients treated with vedolizumab. Vedolizumab is a gut-selective monoclonal antibody against alpha4beta7 integrin. Researchers collected stool before treatment and after 52 weeks, then sequenced the 16S rRNA V3-V4 region. They compared diversity and taxa, tracked treatment response, and tested whether 12 months of prophylactic isoniazid changed the microbiota or efficacy.
Who was studied?
The study enrolled 45 adults with moderate-to-severe active UC at a single center, Jinhua Hospital, Zhejiang University, China, treated from 2021 to 2022. Mean age was roughly 48 to 57 years across groups. 24 patients had LTBI and 21 did not. Among LTBI patients, 13 received prophylactic isoniazid (Group A) and 11 did not (Group B). In total 66 fecal samples were analyzed. Baseline age, body mass index, disease duration and Mayo score were comparable between groups.
What were the most important findings?
Patients with LTBI had lower gut microbial diversity than those without, with significantly reduced Shannon and Simpson indices and distinct beta diversity. Enterobacteriaceae dominated the non-LTBI group, while Streptococcaceae and Sutterellaceae were enriched with LTBI. Vedolizumab was effective: at 52 weeks, intention-to-treat clinical response was 83.3% and remission 75.0%, with mucosal response 69.2%. After treatment, unique taxa and Firmicutes increased, Roseburia decreased, and Ruminococcus rose. Prophylactic isoniazid produced no significant difference in efficacy versus no prophylaxis.
What are the greatest implications of this study?
The findings suggest LTBI itself lowers gut microbial diversity in UC, and that vedolizumab remains effective while shifting the microbiota toward greater diversity. Because isoniazid monotherapy had limited effect on the microbiota and did not reduce vedolizumab efficacy, it appears a reasonable prophylaxis choice when preventive treatment is considered. Causation is uncertain. This was a small single-center cohort, stool reflects luminal not mucosal microbiota, and the population may have been more refractory, so larger prospective studies are needed.