Gallstone and bile microbiota: A case-control study based on 16S rRNA gene sequencing

BACKGROUND Gallstone (GS), a prevalent biliary disorder, is associated with bile stasis, infection, and cholesterol metabolism. Recent research highlights the potential role of bile microbiota in GS pathogenesis. This is a case control study conducted at Jinshan Hospital between 2022 and 2023. AIM To investigate the relationship between bile microbiota dysbiosis and GS formation, and analyze bile microbiota composition in GS patients. METHODS This is a retrospective analysis conducted at Jinshan Hospital between 2022 and 2023. A total of 40 patients were analyzed, including 25 with GS and 15 with GS-free (GSF). Bile samples from 27 patients were analyzed using 16S rRNA gene sequencing to assess microbial composition. RESULTS Significant differences were found in bile acid profiles between GS and GSF groups, with lower microbial diversity in GS patients, indicated by reduced Shannon, Chao, Ace, and Sobs indices, and a higher Simpson index. At the phylum level, the most abundant taxa in GS patients were Proteobacteria (91.59%), Firmicutes (2.90%), and Actinobacteria (1.70%), while Proteobacteria (79.81%), Firmicutes (9.67%), and Bacteroidota (3.80%) were predominated in the GSF group. Notably, Achromobacter was more abundant in GS patients, while Acinetobacter , Lactobacillus , and Prevotella were enriched in the GSF group, suggesting their potential protective role against GS formation. CONCLUSION Dysbiosis, particularly overgrowth of Proteobacteria , may contribute to gallstone formation, while Lactobacillus could play a protective role. Further research is needed to validate these findings.