Emerging evidence highlights the role of biliary microbiota in hepato-biliary-pancreatic diseases. The characteristics of biliary microbiota in malignant bile duct obstruction remain poorly understood. This study aims to investigate the composition and metabolic functions of biliary microbiota in patients with malignant obstruction.

Eligible patients were enrolled in this prospective study at First Affiliated Hospital of Soochow University between December 2022 and October 2023, including distal cholangiocarcinoma, hilar cholangiocarcinoma, pancreatic ductal adenocarcinoma, periampullary carcinoma, and gallbladder carcinoma. The patients with choledocholithiasis served as controls. Bile samples were collected via endoscopic retrograde cholangiopancreatography. Microbiota identification was performed using 16S rRNA sequencing, while bile acids were analyzed using mass spectrometry.

A total of 56 patients were successfully enrolled in this study, 25 in the tumor group and 31 in the stone group. A distinct biliary microbial community was observed in patients with malignant bile duct obstruction, consisting of Prevotella, Uruburuella, Atopostipes, Clostridium IV, Halomonas, Tannerella, Porphyromonas, Achromobacter, Rouxiella, Campylobacter, Corynebacterium, Turicibacter, Muribaculum, Selenomonas, and Alloprevotella at genus level. Notably, Clostridium IV, Halomonas, Rouxiella, and Turicibacter were exclusively present in the tumor group. Bile acid levels were significantly lower in the tumor group (P < 0.05), except for ursodeoxycholic acid and taurocholic acid. Additionally, 22 metabolic pathways were enriched in the tumor group.

This study elucidates the community and metabolic potential of biliary microbiota in malignant bile duct obstruction. The findings offer valuable insights for disease assessment and provide a foundation for further research into the role of biliary microbiota in malignancy.

The exact triggers of gallstone formation remain incompletely understood, but research indicates that microbial infection is a significant factor and can interfere with treatment. There is no consensus on the bile microbial culture profiles in previous studies, and determining the microbial profile could aid in targeted prevention and treatment. The primary aim of this study is to investigate the differences in microbial communities cultured from bile specimens of patients with gallstones.

We collected the clinical characteristics and bile microbial status of 9,939 gallstone patients. Statistical analysis was employed to assess the relationship between microbes and clinical features, and a random forest model was utilized to predict recurrence.

Results showed a higher proportion of females among patients, with the age group of 60-74 years being the most prevalent. The most common type of gallstone was solitary gallbladder stones. A total of 76 microbes were cultured from 5,153 patients, with Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis being the most frequently identified. Significant differences in microbial diversity and positive detection rates were observed across different age groups, types of gallstones, and recurrence status. Positive frequencies of E. coli, Enterococcus faecium, and K. pneumoniae varied significantly by age group and gallstone type. The microbial diversity in the recurrence group was significantly lower compared to the non-recurrence group. The recurrence rate was significantly higher in the group with single microbial species compared to those with no microbes or multiple microbes. For the recurrence group, there were significant differences in the frequencies of seven microbes (Aeromonas hydrophila, Enterococcus casseliflavus, Enterococcus faecium, E. coli, K. pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa) before and after recurrence, with these microbes appearing in a higher number of patients after recurrence. Regression analysis identified patient age, stone size, diabetes, venous thrombosis, liver cirrhosis, malignancy, coronary heart disease, and the number of microbial species as important predictors of recurrence. A random forest model constructed using these variables demonstrated good performance and high predictive ability (ROC-AUC = 0.862).

These findings highlight the significant role of microbial communities in gallstone formation and recurrence. Furthermore, the identified predictors of recurrence, including clinical factors and microbial diversity, may help develop personalized prevention and recurrence strategies for gallstone patients.

Cholesterol gallstone disease is a prevalent condition that has a significant economic impact. However, the role of the bile microbiome in its development and the host's responses to it remain poorly understood.

In this study, we conducted a comprehensive analysis of microbial and human bile proteins in 40 individuals with either gallstone disease or gallbladder polyps. We employed a combined proteomic and metaproteomic approach, as well as meta-taxonomic analysis, functional pathway enrichment, and Western blot analyses.

Our metaproteomic analysis, utilizing the lowest common ancestor algorithm, identified 158 microbial taxa in the bile samples. We discovered microbial taxa that may contribute to gallstone formation, including β-glucuronidase-producing bacteria such as Streptococcus, Staphylococcus, and Clostridium, as well as those involved in biofilm formation like Helicobacter, Cyanobacteria, Pseudomonas, Escherichia coli, and Clostridium. Furthermore, we identified 2,749 human proteins and 87 microbial proteins with a protein false discovery rate (FDR) of 1% and at least 2 distinct peptides. Among these proteins, we found microbial proteins crucial to biofilm formation, such as QDR3, ompA, ndk, pstS, nanA, pfIB, and dnaK. Notably, QDR3 showed a gradual upregulation from chronic to acute cholesterol gallstone disease when compared to polyp samples. Additionally, we discovered other microbial proteins that enhance bacterial virulence and gallstone formation by counteracting host oxidative stress, including sodB, katG, rbr, htrA, and ahpC. We also identified microbial proteins like lepA, rtxA, pckA, tuf, and tpiA that are linked to bacterial virulence and potential gallstone formation, with lepA being upregulated in gallstone bile compared to polyp bile. Furthermore, our analysis of the host proteome in gallstone bile revealed enhanced inflammatory molecular profiles, including innate immune molecules against microbial infections. Gallstone bile exhibited overrepresented pathways related to blood coagulation, folate metabolism, and the IL-17 pathway. However, we observed suppressed metabolic activities, particularly catabolic metabolism and transport activities, in gallstone bile compared to polyp bile. Notably, acute cholelithiasis bile demonstrated significantly impaired metabolic activities compared to chronic cholelithiasis bile.

Our study provides a comprehensive metaproteomic analysis of bile samples related to gallstone disease, offering new insights into the microbiome-host interaction and gallstone formation mechanism.

Endoscopic retrograde cholangiopancreatography (ERCP) is an effective minimally invasive operation for the management of choledocholithiasis, while successful extraction is hampered by large diameter of stones. Emerging studies have revealed the close correlation between biliary microbiota and common bile duct stones (CBDS). In this study, we aimed to investigate the community characteristics and metabolic functions of biliary microbiota in patients with giant CBDS.

Eligible patients were prospectively enrolled in this study in First Affiliated Hospital of Soochow University from February 2022 to October 2022. Bile samples were collected through ERCP. The microbiota was analyzed using 16S rRNA sequencing. Metabolic functions were predicted by PICRUSTs 2.0 calculation based on MetaCyc database. Bile acids were tested and identified using ultra performance liquid chromatography-tandem mass spectrometry.

A total of 26 patients were successfully included into final analysis, 8 in giant stone (GS) group and 18 in control group. Distinct biliary microbial composition was identified in patients with giant CBDS, with a significantly higher abundance of Firmicutes at phylum level. The unique composition at genus level mainly consisted of Enterococcus, Citrobacter, Lactobacillus, Pyramidobacter, Bifidobacterium and Shewanella. Pyramidobacter was exclusively found in GS group, along with the absence of Robinsoniella and Coprococcus. The contents of free bile acids were significantly higher in GS group, including cholic acid (98.39μmol/mL vs. 26.15μmol/mL, p=0.035), chenodesoxycholic acid (54.69μmol/mL vs. 5.86μmol/mL, p=0.022) and ursodeoxycholic acid (2.70μmol/mL vs. 0.17μmol/mL, p=0.047). Decreasing tendency of conjugated bile acids were also observed. Metabolic pathways concerning cholelithiasis were abundant in GS group, including geranylgeranyl diphosphate biosynthesis, gluconeogenesis, glycolysis and L-methionine biosynthesis.

This study demonstrated the community structure and metabolic potential of biliary microbiota in patients with giant CBDS. The unique biliary microbial composition holds valuable predictive potential for clinical conditions. These findings provide new insights into the etiology of giant CBDS from the perspective of biliary microbiota.

Cholelithiasis is a common digestive disease affecting 10% to 15% of adults. It imposes significant global health and financial burdens. However, the pathogenesis of cholelithiasis involves several factors and is incompletely elucidated. In addition to genetic predisposition and hepatic hypersecretion, the pathogenesis of cholelithiasis might involve the gastrointestinal (GI) microbiome, consisting of microorganisms and their metabolites. High-throughput sequencing studies have elucidated the role of bile, gallstones, and the fecal microbiome in cholelithiasis, associating microbiota dysbiosis with gallstone formation. The GI microbiome may drive cholelithogenesis by regulating bile acid metabolism and related signaling pathways. This review examines the literature implicating the GI microbiome in cholelithiasis, specifically gallbladder stones, choledocholithiasis, and asymptomatic gallstones. We also discuss alterations of the GI microbiome and its influence on cholelithogenesis.

Background: Laparoscopic common bile duct exploration (LCBDE) and endoscopic retrograde cholangiopancreatography (ERCP) are two methods of retrieving common bile duct (CBD) stones. Aspects of CBD stone management, such as sphincterotomy, have been implicated as risks for CBD stone recurrence although evidence is weak. The aim of this study was to compare stone recurrence following LCBDE and/or ERCP. Methods: Data were collected retrospectively for patients undergoing LCBDE and/or ERCP for CBD stones at a single center from 2008 to 2018. Primary outcome was stone recurrence (>6 months after duct clearance). Risk factors for recurrence were assessed using univariate and multivariate analyses. Results: A total of 445 patients underwent LCBDE-only, 79 patients underwent ERCP-only and 80 patients underwent LCBDE-ERCP. LCBDE-only patients were younger and preoperatively less morbid than ERCP-only patients. Although there was no significant difference for recurrence, there was a trend toward higher recurrence with ERCP-only compared with LCBDE-only and LCBDE-ERCP (5.1% versus 2.0% and 2.5%, P = .280). On univariate comparison, patients with a recurrence were significantly older, had a higher admission white cell count, higher number of ERCPs, increased transampullary stent use, and higher maximum CBD diameter. Total number of ERCP was the only independent predictor of stone recurrence (odds ratio 6.85 [2.55-18.42], P < .001) following multivariate regression. Conclusion: Management plan was not associated with stone recurrence. The total number of ERCP was the only independent predictor of recurrence. Within the limitations of case selection and bias toward LCBDE, this study suggests that limiting repeated ERCP may reduce CBD stone recurrence.