Primary choledocholithiasis occurrence and recurrence is synergetcally modulated by the bile microbiome and metabolome alternations.

AIMS: Primary choledocholithiasis is a common digestive disease with high morbidity and relapse. However, the compositions and functions of the bile microbial ecosystem and the pathogenesis of microfloral regulation of host metabolism resulting in stone formation are poorly understood.

MAIN METHODS: Biliary samples collected from patients with acute cholangitis induced by benign biliary stricture (nonlithiasis group, n = 17) and primary choledocholithiasis (lithiasis group, n = 33) were subjected to multiomics analyses. Furthermore, clinicopathological features collected over a 24-month follow-up period were examined to evaluate the predictive value of candidate microbes.

KEY FINDINGS: Five alpha diversity indices of the bile microbiome were significantly decreased in the lithiasis group. Furthermore, we identified 49 differential bile flora between the two groups, and the relative abundances of 6 bacteria, Actinobacteria, Actinobacteriota, Staphylococcales, Micrococcales, Altererythrobacter and Carnobacteriaceae, were associated with primary choledocholithiasis relapse conditions. Multiomics analyses showed that specific changes in disease-related bacterial taxa were closely related to metabolite variation (low-molecular weight carboxylic acids, sterol liquid and acylcarnitine), which might reflect disease prognosis. According to microbiomic and metabolomic pathway analyses, we revealed that bacterial infections, microbiota-derived amino acid metabolites and secondary bile acid-related pathways were significantly enriched in the stone-formation group, suggesting a novel host-microbial metabolic mechanism of primary choledocholithiasis.

SIGNIFICANCE: Our study first indicates bile host-microbial dysbiosis modulates the abnormal accumulation of metabolites might further disrupt calcium homeostasis and generate insoluble saponification. Additionally, we determined the predictive value of Actinomycetes phylum reduction for recurrence in primary common bile duct stone patients.