Changes in gut microbiota composition and diversity associated with post-cholecystectomy diarrhea.

Background Post-cholecystectomy diarrhea (PCD) frequently occurs in patients following gallbladder removal. PCD is part of the post-cholecystectomy (PC) syndrome, and is difficult to treat. After cholecystectomy, bile enters the duodenum directly, independent of the timing of meals. The interaction between the bile acids and the intestinal microbes is changed. Therefore, the occurrence of PCD may be related to the change in microbiota. However, little is known about the relationship between the gut microbiota and PCD. Aim To better understand the role of the gut microbiota in PCD patients. Methods Fecal DNA was isolated. The diversity and profiles of the gut microbiota were analyzed by performing high-throughput 16S rRNA gene sequencing. The gut microbiota were characterized in a healthy control (HC) group and a PC group. Subsequently, the PC group was further divided into a PCD group and a post-cholecystectomy non-diarrhea group (PCND) according to the patients' clinical symptoms. The composition, diversity and richness of microbial communities were determined and compared. Results In the PC and HC groups, 720 operational taxonomic units (OTUs) were identified. The PC group had fewer OTUs than the HC group. β-diversity was decreased in the PC group. This indicated decreased microbial diversity in the PC group. Fifteen taxa with differential abundance between the HC and PC groups were identified. In the PCD group compared to the PCND group, significant decreases in microbial diversity, Firmicutes/Bacteroidetes ratio, and richness of probiotic microbiota (Bifidobacterium and Lactococcus), and an increase in detrimental microbiota (Prevotella and Sutterella) were observed. Moreover, a negative correlation was found between Prevotella and Bifidobacterium. Using a Kyoto Encyclopedia of Genes and Genomes functional analysis, it was found that the abundances of gut microbiota involved in lipid metabolism pathways were markedly lower in the PCD group compared to the PCND group. Conclusion This study demonstrated that gut dysbiosis may play a critical role in PCD, which provides new insights into therapeutic options for PCD patients.