Pathogenesis of calcium bilirubinate gallstone: role of E. coli, beta-glucuronidase and coagulation by inorganic ions, polyelectrolytes and agitation

Characterization of biliary and duodenal microbiota in patients with primary and recurrent choledocholithiasis

Purpose

To explore the biliary and duodenal microbiota features associated with the formation and recurrence of choledocholithiasis (CDL).

Methods

We prospectively recruited patients with primary (P-CDL, n = 29) and recurrent CDL (R-CDL, n = 27) for endoscopic retrograde cholangiopancreatography (ERCP). Duodenal mucosa (DM), bile and bile duct stones (BDS) samples were collected in P- and R-CDL patients. DM samples were also collected in 8 healthy controls (HC). The microbiota profile analysis was performed with 16S rRNA gene sequencing.

Results

Short-course antibiotic application before ERCP showed no significant effects in alpha and beta diversities of the biliary and duodenal microbiota in CDL. Alpha diversity showed no difference between DM and bile samples in CDL. The duodenal microbial richness and diversity was lower in both P- and R-CDL than HC. The biliary microbiota composition showed a high similarity between P- and R-CDL. Fusobacterium and Enterococcus were higher abundant in DM, bile, and BDS samples of R-CDL than P-CDL, as well as Escherichia and Klebsiella in bile samples of R-CDL. The enriched duodenal and biliary bacteria in CDL were closely associated with cholecystectomy, inflammation and liver dysfunction. The bile-associated microbiota of R-CDL expressed enhanced capacity of D-glucuronide and D-glucuronate degradation, implicating an elevated level of β-glucuronidase probably produced by enriched Escherichia and Klebsiella in bile.

Conclusions

The duodenal microbiota was in an imbalance in CDL. The duodenal microbiota was probably the main source of the biliary microbiota and was closely related to CDL formation and recurrence. Enterococcus, Fusobacterium, Escherichia and Klebsiella might contribute to CDL recurrence.

Clinical trials

The study was registered at the Chinese Clinical Trial Registry (https://www.chictr.org.cn/index.html, ChiCTR2000033940).

Supplementary Information

The online version contains supplementary material available at 10.1007/s13755-023-00267-2.

Investigating the influence of the gut microbiome on cholelithiasis: unveiling insights through sequencing and predictive modeling

BACKGROUND

Cholelithiasis is one of the most common disorders of hepatobiliary system. Gut bacteria may be involved in the process of gallstone formation and are, therefore considered as potential targets for cholelithiasis prediction.

OBJECTIVE

To reveal the correlation between cholelithiasis and gut bacteria.

METHODS

Stool samples were collected from 100 cholelithiasis and 250 healthy individuals from Huzhou Central Hospital; The 16S rRNA of gut bacteria in the stool samples was sequenced using the third-generation Pacbio sequencing platform; Mothur v.1.21.1 was used to analyze the diversity of gut bacteria; Wilcoxon rank-sum test and linear discriminant analysis of effect sizes (LEfSe) were used to analyze differences in gut bacteria between patients suffering from cholelithiasis and healthy individuals; Chord diagram and Plot-related heat maps were used to analyze the correlation between cholelithiasis and gut bacteria; six machine algorithms were used to construct models to predict cholelithiasis.

RESULTS

There were differences in the abundance of gut bacteria between cholelithiasis and healthy individuals, but there were no differences in their community diversity. Increased abundance of Costridia, Escherichia flexneri, and Klebsiella pneumonae were found in cholelithiasis, while Bacteroidia, Phocaeicola, and Phocaeicola vulgatus were more abundant in healthy individuals. The top four bacteria that were most closely associated with cholelithiasis were Escherichia flexneri, Escherichia dysenteriae, Streptococcus salivarius, and Phocaeicola vulgatus. The cholelithiasis model based on CatBoost algorithm had the best prediction effect (sensitivity: 90.48%, specificity: 88.32%, and AUC: 0.962).

CONCLUSION

The identification of characteristic gut bacteria may provide new predictive targets for gallstone screening. As being screened by the predictive model, people at high risk of cholelithiasis can determine the need for further testing, thus enabling early warning of cholelithiasis.

The dysregulation of biliary tract microflora is closely related to primary choledocholithiasis: a multicenter study

Bile microecology changes play an important role in the occurrence and development of choledocholithiasis. At present, there is no clear report on the difference of bile microecology between asymptomatic patients with gallbladder polyps and choledocholithiasis. This study compared bile microecology between gallbladder polyp patients and patients with choledocholithiasis to identify risk factors for primary choledocholithiasis. This study was conducted in 3 hospitals in different regions of China. Bile samples from 26 patients with gallbladder polyps and 31 patients with choledocholithiasis were collected by laparoscopic cholecystectomy and endoscopic retrograde choledocholithiasis cholangiography (ERCP), respectively. The collected samples were used for 16S ribosomal RNA sequencing and liquid chromatography mass spectrometry analysis. The α-diversity of bile microecological colonies was similar between gallbladder polyp and choledocholithiasis, but the β-diversity was different. Firmicutes, Proteobacteri, Bacteroidota and Actinobacteriota are the most common phyla in the gallbladder polyp group and choledocholithiasis group. However, compared with the gallbladder polyp patients, the abundance of Actinobacteriota has significantly lower in the choledocholithiasis group. At the genera level, the abundance of a variety of bacteria varies between the two groups, and Enterococcus was significantly elevated in choledocholithiasis group. In addition, bile biofilm formation-Pseudomonas aeruginosa was more metabolically active in the choledocholithiasis group, which was closely related to stone formation. The analysis of metabolites showed that a variety of metabolites decreased in the choledocholithiasis group, and the concentration of beta-muricholic acid decreased most significantly. For the first time, our study compared the bile of gallbladder polyp patients with patients with choledocholithiasis, and suggested that the change in the abundance of Actinobacteriota and Enterococcus were closely related to choledocholithiasis. The role of Pseudomonas aeruginosa biofilm in the formation of choledocholithiasis was discovered for the first time, and some prevention schemes for choledocholithiasis were discussed, which has important biological and medical significance.

How traditional Chinese medicine can prevent recurrence of common bile duct stones after endoscopic retrograde cholangiopancreatography?

Common bile duct stones, as a type of cholelithiasis, are a benign biliary obstruction that easily acute abdominalgia, and Endoscopic Retrograde Cholangiopancreatography (ERCP) is usually the first choice for clinical treatment. However, the increasing recurrence rate of patients after treatment is troubling clinicians and patients. For the prevention of recurrence after ERCP, there is no guideline to provide a clear drug regimen, traditional Chinese medicine however has achieved some result in the treatment of liver-related diseases based on the "gut-liver-bile acid axis". On the basis of this, this article discusses the possibility of traditional Chinese medicine to prevent common bile duct stones (CBDS) after ERCP, and we expect that this article will provide new ideas for the prevention of recurrence of CBDS and for the treatment of cholelithiasis-related diseases with traditional Chinese medicine in future clinical and scientific research.

The role of bacteria in gallstone formation

Gallstones are a prevalent biliary system disorder that is particularly common in women. They can lead to various complications, such as biliary colic, infection, cholecystitis, and even gallbladder cancer. However, the etiology of gallstones remains incompletely understood. The significant role of bacteria in gallstone formation has been demonstrated in recent studies. Certain bacteria not only influence bile composition and the gallbladder environment but also actively participate in stone formation by producing enzymes such as β-glucuronidase and mucus. Therefore, this review aimed to analyze the mechanisms involving the types and quantities of bacteria involved in gallstone formation, providing valuable references for understanding the etiology and clinical treatment of gallstones.

Features of Metabolite Changes in Disease Evolution in Cholecystolithiasis

BACKGROUND

Cholecystolithiasis is defined as a disease caused by complex and changeable factors. Advanced age, female sex, and a hypercaloric diet rich in carbohydrates and poor in fiber, together with obesity and genetic factors, are the main factors that may predispose people to choledocholithiasis. However, serum biomarkers for the rapid diagnosis of choledocholithiasis remain unclear.

AIMS

This study was designed to explore the pathogenesis of cholecystolithiasis and identify the possible metabolic and lipidomic biomarkers for the diagnosis of the disease.

METHODS

Using UHPLC-MS/MS and GC-MS, we detected the serum of 28 cholecystolithiasis patients and 19 controls. Statistical analysis of multiple variables included Principal Component Analysis (PCA). Visualization of differential metabolites was performed using volcano plots. The screened differential metabolites were further analyzed using clustering heatmaps. The quality of the model was assessed using random forests.

RESULTS

In this study, dramatically altered lipid homeostasis was detected in cholecystolithiasis group. In addition, the levels of short-chain fatty acids and amino acids were noticeably changed in patients with cholecystolithiasis. They detected higher levels of FFA.18.1, FFA.20.1, LPC16.0, and LPC20.1, but lower levels of 1-Methyl-L-histidine and 4-Hydroxyproline. In addition, glycine and L-Tyrosine were higher in choledocholithiasis group. Analyses of metabolic serum in affected patients have the potential to develop an integrated metabolite-based biomarker model that can facilitate the early diagnosis and treatment of the disease.

CONCLUSION

Our results highlight the value of integrating lipid, amino acid, and short-chain fatty acid to explore the pathophysiology of cholecystolithiasis disease, and consequently, improve clinical decision-making.

Elevated plasma and bile levels of corisin, a microbiota-derived proapoptotic peptide, in patients with severe acute cholangitis

BACKGROUND

Acute cholangitis is a severe, life-threatening infection of the biliary system that requires early diagnosis and treatment. The Tokyo Guidelines recommend a combination of clinical, laboratory, and imaging findings for diagnosis and severity assessment, but there are still challenges in identifying severe cases that need immediate intervention. The microbiota and its derived products have been implicated in the pathogenesis of acute cholangitis. Corisin is a microbiome-derived peptide that induces cell apoptosis, acute tissue injury, and inflammation. This study aimed to evaluate the potential of plasma and bile corisin as a biomarker of acute cholangitis.

METHODS

Forty patients with acute cholangitis associated with choledocholithiasis or malignant disease were enrolled. Nine patients without acute cholangitis were used as controls. Corisin was measured by enzyme immunoassays in plasma and bile samples. Patients were classified into severe and non-severe groups. The associations of plasma and bile corisin with the clinical grade of acute cholangitis and other parameters were analyzed by univariate and multivariate regression analysis.

RESULTS

Plasma and bile corisin levels were significantly higher in patients with acute cholangitis than in controls. Patients with severe acute cholangitis had significantly higher plasma and bile corisin levels than those with non-severe form of the disease. Bile corisin level was significantly correlated with markers of inflammation, coagulation, fibrinolysis, and renal function. Univariate analysis revealed a significant association of bile corisin but a weak association of plasma corisin with the clinical grade of acute cholangitis. In contrast, multivariate analysis showed a significant relationship between plasma corisin level and the disease clinical grade. The receiver operating characteristic curve analysis showed low sensitivity but high specificity for plasma and bile corisin to detect the severity of acute cholangitis. The plasma and bile corisin sensitivity was increased when serum C-reactive protein level was included in the receiver operating characteristic curve analysis.

CONCLUSIONS

Overall, these findings suggest that plasma and bile corisin levels may be useful biomarkers for diagnosing and monitoring acute cholangitis and that corisin may play a role in the pathophysiology of the disease by modulating inflammatory, coagulation and renal pathways.

Characteristics and metabolic potential of biliary microbiota in patients with giant common bile duct stones

Background

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.

Methods

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.

Results

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.

Conclusions

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.

The Impact of Metabolic Factors and Lipid-Lowering Drugs on Common Bile Duct Stone Recurrence after Endoscopic Sphincterotomy with Following Cholecystectomy

BACKGROUND

Recurrent common bile duct stone after endoscopic retrograde cholangiopancreatography is an undesirable problem, even when a following cholecystectomy is carried out. Important factors are the composition and properties of stones; the most significant etiology among these is the lipid level. While numerous studies have established the association between serum lipid levels and gallstones, no study has previously reported on recurrent common bile duct stones after endoscopic sphincterotomy with following cholecystectomy.

MATERIALS AND METHODS

We retrospectively collected 2016 patients underwent endoscopic sphincterotomy from 1 January 2015 to 31 December 2017 in Linkou Chang Gung Memorial Hospital. Finally, 303 patients whose serum lipid levels had been checked following a cholecystectomy after ERCP were included for analysis. We evaluated if metabolic factors including body weight, BMI, HbA1C, serum lipid profile, and lipid-lowering drugs may impact the rate of common bile duct stone recurrence. Furthermore, we tried to find if there is any factor that may impact time to recurrence.

RESULTS

A serum HDL level ≥ 40 (p = 0.000, OR = 0.207, 95% CI = 0.114-0.376) is a protective factor, and a total cholesterol level ≥ 200 (p = 0.004, OR = 4.558, 95% CI = 1.625-12.787) is a risk factor of recurrent common bile duct stones after endoscopic sphincterotomy with cholecystectomy. Lipid-lowering drugs, specifically statins, have been shown to reduce the risk of recurrence significantly (p = 0.003, OR = 0.297, 95% CI = 0.132-0.665). No factors were found to impact the time to recurrence in this study.

CONCLUSIONS

The serum lipid level could influence the recurrence of common bile duct stones after endoscopic sphincterotomy followed by cholecystectomy, and it appears that statins can reduce the risk of recurrence.

The Role of the Bile Microbiome in Common Bile Duct Stone Development

INTRODUCTION

Common bile duct (CBD) stones are a health concern for 10-20% of individuals with symptomatic gallstones, leading to health complications and placing a burden on healthcare systems. This study was initiated to investigate the changes in microbiome compositions and the metabolic signature associated with CBD stones. The research approach integrated taxonomic and functional data with metabolomics data, complemented by in vivo experiments.

METHODS

In a single tertiary healthcare institution, a total of 25 patients were enrolled who had undergone endoscopic retrograde cholangiopancreatography (ERCP) between February 2019 and January 2021. We harvested DNA from bile samples acquired from these individuals. The amplification of the bacterial 16S rRNA gene V3-V4 region was conducted through polymerase chain reaction (PCR), followed by sequencing. We utilized QIIME2 for a comprehensive data analysis. Furthermore, we performed a metabolomic analysis of the bile samples using nuclear magnetic resonance (NMR) spectroscopy. For the assessment of functional gene enrichment, we employed MetaboAnalyst 5.0. Lastly, we executed in vivo experiments on C57BL/6 mice and undertook histological examinations of tissue samples.

RESULTS

Out of the 25 study subjects, 17 underwent ERCP due to CBD stones (the CBD stone group), while the remaining 8 had the procedure for different reasons (the non-CBD stone group). An alpha diversity analysis showed a significantly greater microbial diversity in the bile samples of the non-CBD stone group (p < 0.01), and a beta diversity analysis confirmed the greater microbial compositional abundance in the gut microbiomes in this group (p = 0.01). A taxonomic analysis revealed that the abundances of Enterococcaceae and Enterococcus were higher in the bile microbiomes of the CBD stone group. A metabolic profile analysis showed that the acetate, formate, and asparagine levels were higher in the CBD stone group. A pathway enrichment analysis showed the metabolic pathways (Arginine and Proline Metabolism, Aspartate Metabolism, Glycine, and Serine Metabolism, and Ammonia Recycling pathways) that were associated with these differences. Preclinical experiments demonstrated systemic inflammation and extracellular trap formation in the CBD stone group.

CONCLUSIONS

Our study highlights the importance of biliary dysbiosis and bile metabolites, specifically acetate and formate, in CBD stone development and progression. These findings have implications for the development of diagnostic and therapeutic strategies using microbiomes for CBD stones.

Causal associations between human gut microbiota and cholelithiasis: a mendelian randomization study

Background

There was some evidence that gut microbiota was closely related to cholelithiasis, but the causal relationship between them remained unclear. In this study, we try to use Two-sample Mendelian randomization (MR) to clarify the potential causal relationship between gut microbiota and cholelithiasis.

Methods

Summary Genome-Wide Association Studies (GWAS) statistical data for gut microbiota was obtained from MiBioGen, and the data of cholelithiasis was obtained from UK Biobank (UKB). Two-sample MR analyses were performed to assess causalities between gut microbiota and cholelithiasis mainly using the inverse-variance weighted (IVW) method. Sensitivity analyses were used to determine the robustness of the MR results. Reverse MR analyses were performed to examine the reverse causal association.

Results

Our research results, based primarily on the IVW method, support the existence of a causal relationship between nine gut microbial taxa and cholelithiasis. We observed a positive association between Genus Butyrivibrio (p=0.032), Genus Lachnospiraceae_UCG_001 (p=0.015), Genus Ruminococcaceae_NK4A214_group (p=0.003), Genus Ruminococcaceae_UCG_011 (p=0.010) and cholelithiasis, while Order Rhodospirillales (p=0.031), Genus Actinomyces (p=0.010), Genus Phascolarctobacterium (p=0.036), Genus Rikenellaceae_RC9_gutgroup (p=0.023), Genus Ruminococcaceae_UCG_013 (p=0.022) may be associated with a reduced risk of cholelithiasis. We did not find a reverse causal relationship between cholelithiasis and 9 specific gut microbial taxa.

Conclusions

This is the first mendelian randomization study to explore the causalities between specific gut microbiota taxa and cholelithiasis, which may provide new ideas and a theoretical basis for the prevention and treatment of cholelithiasis in the future.

Development and Recovery of Liver Injury in Piglets by Incremental Injection of LPS

This study aimed to explore the effects of the incremental injection of lipopolysaccharide (LPS) on liver histopathology, inflammation, oxidative status, and mitochondrial function in piglets. Forty healthy Duroc × Landrace × Yorkshire castrated boars (21 ± 2 days old, weight 6.84 ± 0.11 kg) were randomly assigned to five groups (n = 8) and then slaughtered on days 0 (group 0, without LPS injection), 1 (group 1), 5 (group 5), 9 (group 9), and 15 (group 15) of LPS injection, respectively. The results showed that, compared to the piglets without LPS injection, LPS injection caused liver injury in the early phase, as manifested by the increased activities of serum liver injury-related parameters (aspartate amino transferase, alanine aminotransferase, alkaline phosphatase, cholinesterase, and total bile acid) on day 1, and impaired liver morphology (disordered hepatic cell cord arrangement, dissolved and vacuolized hepatocytes, karyopycnosis, and inflammatory cell infiltration and congestion) on days 1 and 5. Meanwhile, LPS injection caused liver inflammation, oxidative stress, and mitochondrial dysfunction on days 1 and 5, as reflected by the upregulated mRNA expression of TNF-α, IL-6, IL-1β, TLR4, MyD88, and NF-κB; increased MPO and MDA content; and impaired mitochondrial morphology. However, these parameters were ameliorated in the later phase (days 9~15). Taken together, our data indicate that the incremental injection of the LPS-induced liver injury of piglets could be self-repaired.

Landscape in the gallbladder mycobiome and bacteriome of patients undergoing cholelithiasis with chronic cholecystitis

Gallstone disease (GSD) is associated with changes in the gut and gallbladder bacterial composition, but there is limited information on the role of the fungal community (mycobiome) in disease development. This study aimed to characterize the gallbladder mycobiome profiles and their interactions with bacteriome in GSD. A total of 136 bile and gallstone samples (34 paired for bacteriome, and 33 paired and extra 2 bile samples for mycobiome) were obtained from calculi patients with chronic cholecystitis. Bile and gallstone bacteriome and mycobiome were profiled by 16S and internal transcribed spacer (ITS) rRNA gene sequencing, respectively. Gallbladder bacteriome, mycobiome, and interkingdom and intrakingdom interactions were compared between bile and gallstone. In general, microbial diversity was higher in bile than in gallstone, and distinct microbial community structures were observed among them. Deep Sea Euryarchaeotic Group, Rhodobacteraceae, and Rhodobacterales were microbial biomarkers of bile, while Clostridiales and Eubacterium coprostanoligenes were biomarkers of gallstone. Five fungal taxa, including Colletotrichum, Colletotrichum sublineola, and Epicoccum, were enriched in gallstone. Further ecologic analyses revealed that intensive transkingdom correlations between fungi and bacteria and intrakingdom correlations within them observed in gallstone were significantly decreased in bile. Large and complex fungal communities inhabit the gallbladder of patients with GSD. Gallstone, compared with bile, is characterized by significantly altered bacterial taxonomic composition and strengthened bacterial-bacterial, fungal-fungal, and bacterial-fungal correlations in the gallbladder of patients with GSD.

Macrophages and derived-TNF-α promote lipopolysaccharide-induced upregulation of endogenous β-glucuronidase in the epithelial cells of the bile duct: A possible facilitator of hepatolithiasis formation

BACKGROUND

Hepatolithiasis is prevalent in Southeast Asian regions, and the role of endogenous β-glucuronidase (β-GD) in the formation of hepatolithiasis is being gradually recognised. Revealing the regulation mechanism of the expression of endogenous β-GD will provide new therapeutic strategies for intervening in the formation of hepatolithiasis.

METHODS

Liver specimens from patients with hepatolithiasis were examined by immunohistochemistry to assess the expression of macrophage markers including CD68, CD80, and CD206, as well as that of TNF-α and endogenous β-GD, compared with that in normal liver samples. HiBEpiC cells were co-cultured directly or indirectly with induced M2 macrophages or directly stimulated with TNF-α, and the expression of the endogenous β-GD was examined. A PKC inhibitor, chelerythrine, and an NF-κB inhibitor, pyrrolidine dithiocarbamate (PDTC), were used to elucidate the possible regulation mechanism.

RESULTS

The expression of macrophage markers including CD68 and CD206, as well as that of TNF-α and endogenous β-GD significantly increased in liver specimens from patients with hepatolithiasis compared with that in normal liver samples. The expression of CD68, CD206 and TNF-α was positively correlated with that of endogenous β-GD. When HiBEpiC cells were co-cultured directly or indirectly with M2 macrophages, following stimulation with lipopolysaccharide (LPS), the expression of endogenous β-GD was significantly higher in the indirect co-culture group than that in the direct co-culture group, or in HiBEpiC cells or M2 macrophages cultured alone. Further experiments revealed that following stimulation with LPS, TNF-α secretion increased in both the indirect and direct co-culture groups compared with that in HiBEpiC cells cultured alone. TNF-α increased the expression of endogenous β-GD in HiBEpiC cells, in a dose- and time-dependent manner. In addition, TNF-α significantly increased the expression levels of p-P65 and proliferating cell nuclear antigen (PCNA), and PDTC effectively inhibited the TNF-α-induced expression of PCNA and β-GD.

CONCLUSIONS

Infiltration of macrophages, especially M2 macrophages, may be involved in the hepatolithiasis formation. LPS activates the macrophages, inducing the secretion of TNF-α, which can further increase the expression of endogenous β-GD in the epithelial cells of the bile duct, possibly via the NF-κB/PCNA signalling cascade.

Metagenomic Sequencing of the Gallbladder Microbiome: Bacterial Diversity Does Not Vary by Surgical Pathology

INTRODUCTION

Alterations in the microbiome contribute to the pathogenesis of many gastrointestinal diseases. However, the composition of the microbiome in gallbladder disease is not well described.

METHODS

We aimed to characterize the biliary microbiome in cholecystectomy patients. Bile and biliary stones were collected at cholecystectomy for a variety of surgical indications between 2017 and 2019. DNA was extracted and metagenomic sequencing was performed with subsequent taxonomic classification using Kraken2. The fraction of bacterial to total DNA reads, relative abundance of bacterial species, and overall species diversity were compared between pathologies and demographics.

RESULTS

A total of 74 samples were obtained from 49 patients: 46 bile and 28 stones, with matched pairs from 25 patients. The mean age was 48 years, 76% were female, 29% were Hispanic, and 29% of patients had acute cholecystitis. The most abundant species were Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus pasteurianus. The bacterial fraction in bile and stone samples was higher in acute cholecystitis compared to other non-infectious pathologies (p < 0.05). Neither the diversity nor differential prevalence of specific bacterial species varied significantly between infectious and other non-infectious gallbladder pathologies. Multivariate analysis of the non-infectious group revealed that patients over 40 years of age had increased bacterial fractions (p < 0.05).

CONCLUSIONS

Metagenomic sequencing permits characterization of the gallbladder microbiome in cholecystectomy patients. Although a higher prevalence of bacteria was seen in acute cholecystitis, species and diversity were similar regardless of surgical indication. Additional study is required to determine how the microbiome can contribute to the development of symptomatic gallbladder disease.

Bile Microbiome in Patients with Recurrent Common Bile Duct Stones and Correlation with the Duodenal Microbiome

BACKGROUND

Common bile duct (CBD) stone recurrence is a common late adverse event after CBD stone treatment. In this preliminary study, we compared the bile fluid and duodenum microbial profiles of patients with or without recurrent CBD stones to identify risk factors associated with recurrence.

METHODS

Bile fluid samples of 47 consecutive patients who underwent ERCP for biliary diseases were subjected to microbiome analysis. Nineteen patients were stone-recurrent (SR), and 28 patients were non-stone-recurrent (NSR). Paired samples (duodenum biopsy tissue and bile fluid samples) from five SR patients were used to compare microbiome compositions in the biliary system and duodenum. In addition, we compared the microbiome compositions of these duodenal tissue samples with those 12 controls (gastric ulcer patients without recurrent CBD stones).

RESULTS

Enterococcaceae_unclassified and enterococcus were more abundant in bile fluid in the SR group than in the NSR group (p = 0.002 and p = 0.003, respectively). A comparison of the microbiome compositions of duodenum tissue and bile fluid samples of the five recurrent CBD stone patients revealed proteobacteria compositions were almost identical from the phylum to genus level. In these five patients, alpha and beta diversities were no different in bile fluid and duodenal tissues. Furthermore, a comparison of the microbiome compositions of duodenal mucosa in patients with recurrent CBD stone patients (n = 5) and controls (n = 12) revealed significant differences between microbiome compositions.

CONCLUSIONS

Enterococcus seems to contribute to CBD stone development. Furthermore, our results indicate that retrograde migration of the duodenal microbiome may contribute to bile microbiome alterations. We recommend that more research be conducted to confirm this hypothesis.

Long-term outcomes of endoscopic papillary large-balloon dilation (12-15 mm) with or without limited sphincterotomy for removal of bile duct stones

BACKGROUND

Limited endoscopic sphincterotomy with large balloon dilation (ES-LBD) and endoscopic papillary large-balloon dilation (EPLBD) have been proven safe and effective for removal of bile duct stones. However, the long-term outcomes are not clear. The aim of this study was to assess the long-term outcomes of EPLBD (12-15 mm) with or without limited sphincterotomy for removal of common bile duct (CBD) stones.

METHODS

Patients with EPLBD or ES-LBD referred for the removal of bile-duct stones between June 2008 and August 2020 were retrospectively reviewed. Complete stone clearance, endoscopic retrograde cholangiopancreatography (ERCP)-related adverse events, and late biliary complications during long-term follow-up were analyzed.

RESULTS

Basic patient characteristics were not significantly different between the groups that underwent EPLBD (n = 168) and ES-LBD (n = 57). EPLBD compared with ES-LBD resulted in similar outcomes in terms of overall successful stone removal (99.4% vs. 100%, P = 1.00) and ERCP-related adverse events (7.7% vs. 5.3%, P = 0.77). The mean duration of the follow-up was 113.6 months and 106.7 months for patients with EPLBD and ES-LBD, respectively (P = 0.13). There was no significant difference between EPLBD and ES-LBD in the incidence of stone recurrence [20 (11.9%) vs. 9 (15.8%); P = 0.49]. Multivariate analysis showed that a diameter of CBD ≥ 15 mm (OR = 3.001; 95% CI: 1.357-6.640; P = 0.007) was an independent risk factor for stone recurrence.

CONCLUSIONS

The application of a large balloon (12-15 mm) via EPLBD is an effective and safe alternative to ES-LBD for extraction of large CBD stones. Endoscopic sphincterotomy prior to EPLBD may be unnecessary. A diameter of CBD ≥ 15 mm is a risk factor of stone recurrence.

Healthy Dietary Pattern Reduces Risk of Gallstones: Results of a Case-Control Study in Iran

Background

Nutrition-related factors have been of great interest as one of risk factors of biliary stones. This study evaluated the association of dietary patterns with biliary stone among Iranians.

Methods

This is a hospital-based case-control study, which was conducted in a general hospital in Tehran, Iran. A total of 110 patients with gallstone or common bile duct (CBD) stone confirmed by Ultrasonography within the last 6 months before collecting data were recruited. Controls were age-matched patients admitted to the other wards of the same hospital for a broad spectrum of disorders including traumas and orthopedic conditions, or elective surgeries, or throat/ear/nose disease and had no gallbladder disorders, participated in this study. We used a valid and reliable food frequency questionnaire to assess dietary intakes of participants. Dietary patterns were determined by factor analysis.

Results

By design, age was similar in both groups (57.66 ± 16.39 years vs. 56.00 ± 10.64 years in cases and controls, respectively). Two dietary patterns were extracted; "Unhealthy" (high consumption of artificial juice, processed meats, refined grains, sweets and desserts, pickles, snacks, and red meats), and "Healthy" (high consumption of vegetable oils, vegetables, fruits, fish, legumes, and nuts, as well as low consumption of hydrogenated fats and salt). Participants in the highest tertile of "Healthy" dietary pattern were significantly less likely to have the gallstones disease (OR: 0.33, 95% CI = 0.120.89) compared to the reference group (low tertile of "Healthy" dietary pattern) (P = 0.02).

Conclusions

High consumption of vegetable oils, vegetables, fruits, fish, legumes, and nuts, as well as low consumption of hydrogenated fats and salt in context of healthy dietary pattern are inversely associated with risk of gallstones.

Biliary Diseases from the Microbiome Perspective: How Microorganisms Could Change the Approach to Benign and Malignant Diseases

Recent evidence regarding microbiota is modifying the cornerstones on pathogenesis and the approaches to several gastrointestinal diseases, including biliary diseases. The burden of biliary diseases, indeed, is progressively increasing, considering that gallstone disease affects up to 20% of the European population. At the same time, neoplasms of the biliary system have an increasing incidence and poor prognosis. Framing the specific state of biliary eubiosis or dysbiosis is made difficult by the use of heterogeneous techniques and the sometimes unwarranted invasive sampling in healthy subjects. The influence of the microbial balance on the health status of the biliary tract could also account for some of the complications surrounding the post-liver-transplant phase. The aim of this extensive narrative review is to summarize the current evidence on this topic, to highlight gaps in the available evidence in order to guide further clinical research in these settings, and, eventually, to provide new tools to treat biliary lithiasis, biliopancreatic cancers, and even cholestatic disease.

Clinical features, concurrent disorders, and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome

OBJECTIVE

To characterize clinical features, comorbidities, frequency of bacterial isolation, and survival time in cats with suppurative cholangitis-cholangiohepatitis syndrome (S-CCHS).

ANIMALS

168 client-owned cats with S-CCHS.

PROCEDURES

Data were prospectively (1980 to 2019) collected regarding clinical features, comorbidities, bacterial infection, illness duration, and treatments. Variables were evaluated for associations with survival time.

RESULTS

Median age of cats was 10.0 years, with no breed or sex predilection observed. Common clinical features included hyporexia (82%), hyperbilirubinemia (80%), lethargy (80%), vomiting (80%), jaundice (67%), weight loss (54%), and hypoalbuminemia (50%). Comorbidities included extrahepatic bile duct obstruction (53%), cholelithiasis (42%), cholecystitis (40%), and ductal plate malformation (44%) as well as biopsy-confirmed inflammatory bowel disease (60/68 [88%]) and pancreatitis (41/44 [93%]). Bacterial cultures were commonly positive (69%) despite prebiopsy antimicrobial administration in most cats. Of surgically confirmed choleliths, diagnostic imaging identified only 58%. Among 55 cats with "idiopathic pancreatitis," 28 (51%) were documented to have transiting choleliths, and 20 had pancreatic biopsies confirming pancreatitis. Cholelithiasis (with or without bile duct obstruction) and cholecystectomy were associated with survival advantages. Survival disadvantages were found for leukocytosis, ≥ 2-fold increased alkaline phosphatase, and hyperbilirubinemia. Cholecystoenterostomy had no survival impact. Cats with ductal plate malformations were significantly younger at diagnosis and death than other cats. Chronic treatments with antimicrobials, S-adenosylmethionine, and ursodeoxycholic acid were common postbiopsy.

CLINICAL RELEVANCE

S-CCHS in cats was associated with bacterial infection and various comorbidities and may be confused with pancreatitis. Surgically correctable morbidities (ie, cholecystitis, cholecystocholelithiasis) and cholecystectomy provided a significant survival advantage.

Analysis on Microbial Profiles & Components of Bile in Patients with Recurrent CBD Stones after Endoscopic CBD Stone Removal: A Preliminary Study

Background/Aim: Common bile duct (CBD) stone recurrence after endoscopic treatment is a major concern as a late complication. Biliary bacterial factors and biochemical factors determine the path of gallstone formation. The aim of this preliminary study was to investigate the microbial profile and components of bile in patients with and without recurrent CBD stones after endoscopic CBD stone removal. Methods: Among patients who had undergone an initial endoscopic procedure for the removal of CBD stones and were followed up for >2 years, 11 patients who experienced at least two CBD stone recurrences, six months after endoscopic retrograde cholangiopancreatography (ERCP), were categorized into the recurrence group. Nine patients without CBD recurrence events were matched. Results: Polymicrobial infections are generally seen in all patients who have biliary sphincteroplasty. Microbial richness, measured by the numbers of operational taxonomic units (OTUs), was reduced in the recurrence group. The microbial evenness was also significantly lower than in the non-recurrence group. The overall microbial communities in the recurrence group deviated from the non-recurrence group. Infection with bacteria exhibiting β-glucuronidase activity was more frequent in the recurrence group, but there was no statistical significance. In an analysis of the bile components, the bile acid concentration was higher in the non-recurrence group than in the recurrence group. However, the other metabolites were not significantly different. Conclusions: Microbiota dysbiosis and altered bacterial community assembly in bile duct and decreased bile acid in bile juice were associated with recurrence of bile duct stone.

The imbalance of biliary microflora in hepatolithiasis

BACKGROUND

The imbalance of microbial flora is thought to be associated with many diseases. However, the characteristics of the biliary microflora and its relation to in hepatolithiasis are unknown.

METHODS

This study included 40 patients with hepatolithiasis and 10 control patients. Bile samples were taken during hepatectomy surgeries and 16S rRNA sequencing was performed. The sequencing results were analyzed by operational taxonomic unit (OTU) clustering, species annotation and abundance analyses, sample complexity analyses, diversity analyses, and environmental factor correlation analyses.

RESULTS

There were significant differences in bile microflora between the hepatolithiasis group and the control group. We found that the abundance of microflora in the bile of patients with hepatolithiasis was relatively high (52.4% versus 40.2% and 42.1% versus 29.6%). The diversity of microflora in the bile of patients with hepatolithiasis decreased significantly (Shannon (P = 0.004), Observed species (P = 0.001), PD-whole-tree (P = 0.001)). These differences are mainly associated with Enterococcus(P＜0.001), Enterobacter(P = 0.003). In addition, we found that there were intra-group differences in hepatolithiasis, but the differences in the hepatolithiasis group were generally smaller than the differences in the non-hepatolithiasis group.

CONCLUSION

There is an imbalance of microflora in the bile duct of patients with hepatolithiasis. The imbalance of biliary flora may be associated with hepatolithiasis pathogenesis.

Biliary Microbiota in Choledocholithiasis and Correlation With Duodenal Microbiota

Background

The pathogenesis of choledocholithiasis is closely related to the role of bacteria. However, little is known about the predictive role of bile bacteria in clinical conditions of patients and the compositional and functional characteristics of biliary microbiota in choledocholithiasis.

Methods

To investigate the predictive value of biliary bacteria, clinical data of 488 patients with choledocholithiasis were collected. The predictive value of common bile bacteria to patients’ clinical conditions was analyzed by logistic regression. Samples of bile and corresponding duodenal juice from 10 selected patients with choledocholithiasis were obtained, and the composition and function of microbial communities were analyzed based on 16S rRNA sequencing and Tax4Fun.

Results

The clinical conditions of patients with choledocholithiasis, such as recurrence, the severity of acute cholangitis, and duration of hospital stay were closely related to different species of bile bacteria as well as antimicrobial-resistant bacteria. Employing 16S rRNA sequencing, the dominant phyla of biliary and duodenal microbiota were Proteobacteria and Firmicutes. The top three core microbiota at the genus level were Escherichia–Shigella, Fusobacterium, and Enterococcus. Escherichia coli accounted for the most abundant annotated species in both. Differences in composition between biliary and duodenal microbiota were not significant according to the alpha and beta diversities. Differential abundant features were not found in biliary microbiota indicated by A linear discriminant analysis effective size algorithm. The major pathways identified in biliary and duodenal microbiota were related to membrane transport, translation, replication and repair, carbohydrate and amino acid metabolism. However, no significant difference in those major pathways, as well as antimicrobial-resistance patterns, was observed between biliary and duodenal microbiota.

Conclusion

Our study first demonstrates the predictive contribution of biliary bacteria to the clinical conditions of patients with choledocholithiasis, and then it offers new insights into the compositional and functional features of biliary and duodenal microbiota. Similarities between biliary and duodenal microbiota support the theory of bacterial duodenal–biliary reflux in patients with choledocholithiasis. Meanwhile, when it is impracticable to obtain a bile sample, duodenal juice may be used as an alternative for bacterial culture and susceptibility tests.

Bile Microbiota in Patients with Pigment Common Bile Duct Stones

BACKGROUND

Common bile duct (CBD) stone is one of the most prevalent gastroenterological diseases, but the role played by biliary microbiota in the pathogenesis of CBD stones remains obscure. The aim of this study was to investigate the characteristics of the biliary tract core microbiome and its potential association with the formation of pigment stones.

METHODS

Twenty-eight patients with biliary obstruction of various causes were enrolled. Thirteen had new-onset pigment CBD stone. Of the remaining 15, four had benign biliary stricture, four had gallbladder cancer, three had pancreatic cancer, 3 had distal CBD cancer, and one had hepatocellular carcinoma. Endoscopic retrograde cholangiopancreatography was used to collect bile samples for DNA extraction, 16S ribosomal RNA gene sequencing, and bile microbiota composition analysis.

RESULTS

Proteobacteria (61.7%), Firmicutes (25.1%), Bacteroidetes (5%), Fusobacteria (4.6%), and Actinobacteria (2.6%) were the most dominant phyla in the bile of the 28 study subjects. A comparison between new-onset choledocholithiasis and other causes of biliary obstruction (controls) showed Enterococcus was found to be significantly abundant in the CBD stone group at the genus level (linear discriminant analysis score = 4.38; P = 0.03). However, no other significant compositional difference was observed.

CONCLUSION

This study demonstrates an abundance of microbiota in bile juice and presents a biliary microbiome composition similar to that of duodenum. The study also shows Enterococcus was significantly abundant in the bile juice of patients with a brown pigment stone than in controls, which suggests Enterococcus may play an important role in the development of pigment stones.

Human gut bacterial β-glucuronidase inhibition: An emerging approach to manage medication therapy

Bacterial β-glucuronidase enzymes (BGUSs) are at the interface of host-microbial metabolic symbiosis, playing an important role in health and disease as well as medication outcomes (efficacy or toxicity) by deconjugating a large number of endogenous and exogenous glucuronides. In recent years, BGUSs inhibition has emerged as a new approach to manage diseases and medication therapy and attracted an increasing research interest. However, a growing body of evidence underlines great genetic diversity, functional promiscuity and varied inhibition propensity of BGUSs, which have posed big challenges to identifying BGUSs involved in a specific pathophysiological or pharmacological process and developing effective inhibition. In this article, we offered a general introduction of the function, in particular the physiological, pathological and pharmacological roles, of BGUSs and their taxonomic distribution in human gut microbiota, highlighting the structural features (active sites and adjacent loop structures) that affecting the protein-substrate (inhibitor) interactions. Recent advances in BGUSs-mediated deconjugation of drugs and carcinogens and the discovery and applications of BGUS inhibitors in management of medication therapy, typically, irinotecan-induced diarrhea and non-steroidal anti-inflammatory drugs (NSAIDs)-induced enteropathy, were also reviewed. At the end, we discussed the perspectives and the challenges of tailoring BGUS inhibition towards precision medicine.

Advances in Risk Factors for Recurrence of Common Bile Duct Stones

Choledocholithiasis is a chronic common disease. The incidence of cholelithiasis is 5%-15%, of which 5%-30% are combined with Choledocholithiasis. Although endoscopic cholangiopancreatography (ERCP) + endoscopic sphincterotomy (EST) is the most common treatment procedure, which clearance rate is up to 95%, the incidence of recurrent choledocholithiasis was 4%-25%. The risk factors of recurrence after choledocholithiasis clearance are the focuses of current researches, which are caused by multiple factors. We first systematically summarize the risk factors of common bile duct stones (CBDS) recurrence into five aspects: first-episode stone related factors, congenital factors, biological factors, behavioral intervention factors, and the numbers of stone recurrence.

Gallstone Disease, Obesity and the Firmicutes/Bacteroidetes Ratio as a Possible Biomarker of Gut Dysbiosis

Obesity is a major risk factor for developing gallstone disease (GSD). Previous studies have shown that obesity is associated with an elevated Firmicutes/Bacteroidetes ratio in the gut microbiota. These findings suggest that the development of GSD may be related to gut dysbiosis. This review presents and summarizes the recent findings of studies on the gut microbiota in patients with GSD. Most of the studies on the gut microbiota in patients with GSD have shown a significant increase in the phyla Firmicutes (Lactobacillaceae family, genera Clostridium, Ruminococcus, Veillonella, Blautia, Dorea, Anaerostipes, and Oscillospira), Actinobacteria (Bifidobacterium genus), Proteobacteria, Bacteroidetes (genera Bacteroides, Prevotella, and Fusobacterium) and a significant decrease in the phyla Bacteroidetes (family Muribaculaceae, and genera Bacteroides, Prevotella, Alistipes, Paludibacter, Barnesiella), Firmicutes (genera Faecalibacterium, Eubacterium, Lachnospira, and Roseburia), Actinobacteria (Bifidobacterium genus), and Proteobacteria (Desulfovibrio genus). The influence of GSD on microbial diversity is not clear. Some studies report that GSD reduces microbial diversity in the bile, whereas others suggest the increase in microbial diversity in the bile of patients with GSD. The phyla Proteobacteria (especially family Enterobacteriaceae) and Firmicutes (Enterococcus genus) are most commonly detected in the bile of patients with GSD. On the other hand, the composition of bile microbiota in patients with GSD shows considerable inter-individual variability. The impact of GSD on the Firmicutes/Bacteroidetes ratio is unclear and reports are contradictory. For this reason, it should be stated that the results of reviewed studies do not allow for drawing unequivocal conclusions regarding the relationship between GSD and the Firmicutes/Bacteroidetes ratio in the microbiota.

In vitro analysis of gallstone formation in the presence of bacteria

AIM

In our previous study, we have isolated different genera of bacteria from gallstones and this intrigued us to study their role in gallstone formation. The isolates exhibited certain biliary activities like urease activity, slime production, and β-glucuronidase production. We aimed to investigate the role of these factors in the formation of gallstone in in vitro conditions at a supersaturated concentration of cholesterol.

METHODOLOGY

To mimic bile in in vitro state, Brilliant Green Bile Broth (BGBB) media having a composition similar to human bile was used. Four different experimental sets were prepared, each having nine flasks with varying concentrations of cholesterol and CaCO3 (calcium carbonate). Test sets I, II, III, and IV were inoculated with Salmonella, Enterococcus, Helicobacter, and Neisseria respectively, which were isolated from gallstone itself. Out of these four bacteria, only Helicobacter did not possess slime activity. A control set was also established which was devoid of bacteria. The control also had nine flasks with different concentrations of cholesterol and CaCO3. All the sets were incubated in the incubator shaker at 37 °C and 80 revolution per minutes (RPM) for 20 days.

RESULT

It was observed that the sets having bacteria had a less nucleation time as compared to the control (F = 5.274; p < 0.001). Solidification of gallstone was observed only in the set with bacteria having slime activity (sets I, II, and IV).

CONCLUSION

The slime activity of bacteria leads to solidification of gallstones, whereas the other activities accelerate the nucleation of gallstone formation enhancing the severity of the disease.

Gallstone Disease and Microbiome

Gallstone disease (GSD) has, for many years, remained a high-cost, socially significant public health problem. Over the past decade, a number of studies have been carried out—both in humans and in animal models—confirming the role of the microbiota in various sections of the gastrointestinal tract as a new link in the etiopathogenesis of GSD. The microbiome of bile correlates with the bacterial composition of saliva, and the microbiome of the biliary tract has a high similarity with the microbiota of the duodenum. Pathogenic microflora of the oral cavity, through mechanisms of immunomodulation, can affect the motility of the gallbladder and the expression of mucin genes (MUC1,Muc3, MUC4), and represent one of the promoters of stone formation in the gallbladder. The presence of H. pylori infection contributes to the formation of gallstones and affects the occurrence of complications of GSD, including acute and chronic cholecystitis, cholangitis, pancreatitis. Intestinal bacteria (Clostridium, Bifidobacterium, Peptostreptococcus, Bacteroides, Eubacterium, and Escherichia coli) participating in the oxidation and epimerization of bile acids can disrupt enterohepatic circulation and lead to the formation of gallstones. At the same time, cholecystectomy due to GSD leads to the further transformation of the composition of the microbiota in various parts of the gastrointestinal tract, increasing the risk of developing stomach cancer and colorectal cancer. Further research is required to determine the possibility of using the evaluation of the composition of the microbiota of the gastrointestinal and biliary tracts as an early diagnostic marker of various gastroenterological diseases.

Analysis of stones formed in the human gall bladder and kidney using advanced spectroscopic techniques

Stone diseases (gallstones and kidney stones) are extremely painful and often cause death. The prime aim of biomedical research in this area has been determination of factors resulting in stone formation inside the gallbladder and urinary tract. Many theories have been put forward to explain the mechanism of stone formation and their growth; however, their complete cycle of pathogenesis is still under debate. Several factors are responsible for stone formation; however, much emphasis is placed on the determination of elemental and molecular composition of the stones. In the present review article, we describe different kinds of spectroscopic techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF) spectroscopy, time-of-flight secondary ion mass spectrometry (TOF-SIMS), and laser-induced breakdown spectroscopy (LIBS) and highlight their use in the analysis of stone diseases. We have summarized work done on gallstones and kidney stones using these advanced techniques particularly over the last 10 years. We have also briefly elaborated the basics of stone formations inside the human body and their complications for a better understanding of the subject.

Needle-knife fistulotomy vs. standard biliary sphincterotomy for choledocholithiasis: common bile duct stone recurrence and complication rate

Background and study aims  With common bile duct (CBD) stones, access to the CBD can be achieved through the papilla orifice followed by standard biliary sphincterotomy (SBS), or through precut fistulotomy (PF) in case of difficult cannulation. The two methods alter papilla anatomy differently, potentially leading to a different rate of stone recurrence. No data have been published on stone recurrence after PF in patients with CBD stones. The aim of this study was to evaluate CBD stone recurrence, reintervention rate after PF versus SBS, and complications. Patients and methods  This was a retrospective single-center cohort study including patients undergoing for the first time endoscopic retrograde cholangiopancreatography (ERCP) for CBD stones with PF in case of failed repeated cannulation attempts, matched for sex/age to patients with SBS randomly extracted from our database. T -test and Fisher's tests were used for continuous and categorical variable comparison. Recurrence probability was calculated with Kaplan-Meier curve. Factors associated with ERCP repetition were evaluated with logistic regression through a Cox's proportional hazards model. Results  Eighty-five patients with PF were included, with 85 matched controls (mean age 68.7 years, 45.9 % males). Overall, patients with PF had the same reintervention rate as those with SBS (14.1 % vs. 12.9 %) with a hazard ratio (HR) of 1.11 (95 % CI 0.49 - 2.50; P  = 0.81), but mean time to reintervention was significantly lower (74.9 ± 74.6 vs. 765.6 ± 961.3 days; P  < 0.0001), with 100 % of stones recurring within the first year in the PF group vs. 54.5 % in the SBS group ( P  = 0.01). The only factor associated with ERCP repetition risk was incomplete CBD clearing. Complications, including pancreatitis, did not differ significantly. Conclusions  The reintervention rate was significantly higher in the short term after PF. Therefore, closer follow-up in the first 6 to 12 months after ERCP might be appropriate for patients underoing PF.

Proteobacteria Acts as a Pathogenic Risk-Factor for Chronic Abdominal Pain and Diarrhea in Post-Cholecystectomy Syndrome Patients: A Gut Microbiome Metabolomics Study

Background

Laparoscopic cholecystectomy (LC) is regarded as the criterion standard for gallstone therapy, but post-cholecystectomy syndrome (PCS) is a common complication. This study aimed to analyze and identify differences in gut microbiome in PCS patients.

Material/Methods

This study involved 8 PCS patients (RS1), 8 asymptomatic PCS patients (RS2), and 8 healthy individuals (RS3). Genomic DNA of gut microbiome was extracted and amplified with CTAB method. PCR products were sequenced with Illumina High-Through Sequencing. Sequencing data were analyzed with QIIME software. Effective sequence of bacterial 16S-rRNA gene was clustered into OTUs using UPARSE software. Species annotations were evaluated using Mothur software. QIIME software was used to conduct complexity analysis and calculate UniFrac distances. R software was used to generate PCoA plots.

Results

Bacterial 16S-rDNA gene sequences showed that the effective species annotative data were more than 97%. According to Ternary plot, Firmicutes and Bacteroidetes had similar abundance and contents among the 3 groups. Contents of Proteobacteria in RS1 were higher compared to RS2 and RS3. Bacterial genomic DNAs samples were clustered together in the same group; however, distances were relative far between different groups. RS1 illustrated significantly higher abundance of Proteobacteria colonies compared to healthy people (p<0.05), and illustrated higher abundance of Verrucomicrobia and lower abundance of Bacteroidetes and Firmicutes, but without significant differences (p>0.05).

Conclusions

Gut microbiome of PCS patients was dominated by Proteobacteria in feces and contained little Firmicutes and Bacteroidetes. The enhanced abundance of Proteobacteria might be the highly pathogenic risk factor for chronic abdominal pain and diarrhea in PCS patients.

Role of the biliary microbiome in gallstone disease

Gallstone disease is caused by multiple pathogenic factors and is common worldwide. Most studies have focused on the significance of the biliary microbiome in gallstone pathogenesis. Areas covered: In this study, the epidemiology of gallstone diseases and the existence, composition, origin, and mechanisms of the biliary microbiota were reviewed. Mechanisms involved in promoting the formation of different types of gallstones were also emphasized. The antibiotic susceptibility of the biliary microbiota is briefly discussed because it may guide clinical strategies. Expert commentary: The biliary microbiome facilitates the formation of brown pigment stones. Although glycoprotein (mucin) may be pivotal for many promoting substances to coagulate and integrate relevant components, new mechanisms involving prostaglandins, oxysterols, oxygen free radicals, and lipopolysaccharides have been discovered. Furthermore, specific bacterial species such as Helicobacter and Salmonella are involved in the pathogenesis of cholesterol gallstones. Recently, metabolomics of the biliary microbiome has been used to determine the detailed mechanisms that promote gallstone formation. Previously, the bacterial effects involved in the pathogenesis of brown pigment stones have not been analyzed in detail. Whether the administration of antibiotics is related to prophylaxis for gallstone formation and gallstone-associated infections remains unclear.

Gut Microbial β-Glucuronidase Inhibition via Catalytic Cycle Interception

Microbial β-glucuronidases (GUSs) cause severe gut toxicities that limit the efficacy of cancer drugs and other therapeutics. Selective inhibitors of bacterial GUS have been shown to alleviate these side effects. Using structural and chemical biology, mass spectrometry, and cell-based assays, we establish that piperazine-containing GUS inhibitors intercept the glycosyl-enzyme catalytic intermediate of these retaining glycosyl hydrolases. We demonstrate that piperazine-based compounds are substrate-dependent GUS inhibitors that bind to the GUS-GlcA catalytic intermediate as a piperazine-linked glucuronide (GlcA, glucuronic acid). We confirm the GUS-dependent formation of inhibitor-glucuronide conjugates by LC-MS and show that methylated piperazine analogs display significantly reduced potencies. We further demonstrate that a range of approved piperazine- and piperidine-containing drugs from many classes, including those for the treatment of depression, infection, and cancer, function by the same mechanism, and we confirm through gene editing that these compounds selectively inhibit GUS in living bacterial cells. Together, these data reveal a unique mechanism of GUS inhibition and show that a range of therapeutics may impact GUS activities in the human gut.

Metagenomics of pigmented and cholesterol gallstones: the putative role of bacteria

There is growing evidence for bacteria playing a role in the pathogenesis and formation of pigmented gallstones from humans. These studies mainly involved cultivation of gallstone-associated bacteria and 16S rRNA profiling, providing an indirect link between processes involved in gallstone formation by the bacteria in-situ. Here, we provide functional metagenomic evidence of a range of genes involved in bile stress response, biofilm formation, and anaerobic energy metabolism by Gram-negative Klebsiella in pigmented gallstones from a 76-year-old male patient. Klebsiella was also present in one cholesterol-type stone in a 30-year-old female patient who had additional cholesterol gallstones characterised by Gram-positive bacteria. Pigmented stones further revealed a predominance of genes involved in carbohydrate metabolism, whilst cholesterol stones indicated a profile dominanted by protein metabolism possibly reflecting known chemical differences between Gram-negative and Gram-positive biofilm matrices. Archaeal genes were not detected. Complementary carbon and hydrogen isotopic analyses of cholesterol within the patients’ stones revealed homogeneity, suggesting a common diet or cholesterol biosynthesis pathway that has little influence on microbial composition. This pilot study provides a framework to study microbial processes that play a potential role in gallstone formation across markedly different types of stones and patient backgrounds.

The efficacy of resection of intrahepatic bile duct stenosis-causing membrane or septum for preventing hepatolithiasis after choledochal cyst excision

BACKGROUND/PURPOSE

We previously found that many patients who developed hepatolithiasis after choledochal cyst excisions had intrahepatic bile duct stenosis (IHBDS). In 1992, we started resection of the membrane or septum which was found at the site of IHBDS during choledochal cyst excisions. Since intrahepatic stones usually take years to form, the efficacy of this procedure has not been proved.

METHODS

The records of patients who had IHBDS-causing membrane or septum and underwent choledochal cyst excision with Roux-Y hepaticojejunostomy between January 1979 and December 2006 were retrospectively analyzed. The patients who underwent surgical treatment for IHBDS-causing membrane or septum were compared with those who did not undergo the procedure.

RESULTS

Sixty-nine patients met the criteria, and seven patients who were followed up for less than 5years were excluded from the study. Thirty-three patients underwent surgical treatment for IHBDS, and three of them developed intrahepatic stones. Meanwhile, 10 of 29 patients who did not undergo the procedure developed intrahepatic stones. A statistically significant difference in intrahepatic stone formation was observed between the two groups in a log-rank test (P=0.016).

CONCLUSIONS

Meticulous probing and excision of the IHBDS-causing membrane or septum are effective for preventing hepatolithiasis after choledochal cyst excisions.

TYPE OF STUDY

Retrospective Comparative Study.

LEVEL OF EVIDENCE

Level III.

Lipopolysaccharide stimulates endogenous β-glucuronidase via PKC/NF-κB/c-myc signaling cascade: a possible factor in hepatolithiasis formation

Hepatolithiasis is commonly encountered in Southeastern and Eastern Asian countries, but the pathogenesis mechanism of stone formation is still not well understood. Now, the role of endogenous β-glucuronidase in pigment stones formation is being gradually recognized. In this study, the mechanism of increased expression and secretion of endogenous β-glucuronidase during hepatolithiasis formation was investigated. We assessed the endogenous β-glucuronidase, c-myc, p-p65, and p-PKC expression in liver specimens with hepatolithiasis by immunohistochemical staining, and found that compared with that in normal liver samples, the expression of endogenous β-glucuronidase, c-myc, p-p65, and p-PKC in liver specimens with hepatolithiasis significantly increased, and their expressions were positively correlated with each other. Lipopolysaccharide (LPS) induced increased expression of endogenous β-glucuronidase and c-myc in hepatocytes and intrahepatic biliary epithelial cells in a dose- and time-dependent manner, and endogenous β-glucuronidase secretion increased, correspondingly. C-myc siRNA transfection effectively inhibited the LPS-induced expression of endogenous β-glucuronidase. Furthermore, NF-κB inhibitor pyrrolidine dithiocarbamate or PKC inhibitor chelerythrine could effectively inhibit the LPS-induced expression of c-myc and endogenous β-glucuronidase, and the expression of p-p65 was also partly inhibited by chelerythrine. Our clinical observations and experimental data indicate that LPS could induce the increased expression and secretion of endogenous β-glucuronidase via a signaling cascade of PKC/NF-κB/c-myc in hepatocytes and intrahepatic biliary epithelial cells, and endogenous β-glucuronidase might play a possible role in the formation of hepatolithiasis.

Association between diet and gallstones of cholesterol and pigment among patients with cholecystectomy: a case-control study in Korea

BACKGROUND

The prevalence of cholesterol gallstones is high in Western populations, while pigment gallstones are common in Asian populations. Dietary factors are suggested to be associated with gallstone risk, but their relationship with gallstone type has not been evaluated. This study investigated the association between diet and risk of cholesterol gallstone or pigment gallstone in a Korean population whose dietary pattern and type of gallstone were changed during the last 30 years.

METHODS

Patients with cholesterol (n = 40) and pigment (n = 59) gallstones were recruited after laparoscopic cholecystectomy and were compared with those of age- and sex-matched controls without gallstones (n = 99). Dietary intakes were assessed by trained dietitians using a semi-quantitative food frequency questionnaire. Multinomial logistic regression analysis was performed to calculate odds ratios and 95% confidence intervals to examine the associations between diet and risk for type of gallstones adjusted by potential confounders.

RESULTS

Patients with cholesterol gallstone consumed more lipid, animal lipid, beef, pork, and fried food than those with pigment gallstones and control, while patients with pigment gallstone consumed more carbohydrate and noodles than patients with cholesterol gallstone and control. In multinomial logistic regression analysis using control as reference group, dietary pattern with high consumption of beef, pork, and fried food was associated with risk of cholesterol gallstones, while there was no association between the risk of pigment gallstone and dietary pattern. In addition, control consumed more alcohol than patients with cholesterol and pigment gallstones.

CONCLUSIONS

The present study suggested consumption of fat from meat and fried foods increased the risk of cholesterol gallstone, and intake of carbohydrate from noodles increased the risk of pigment gallstone.

The Impact of Cholecystectomy After Endoscopic Sphincterotomy for Complicated Gallstone Disease

OBJECTIVES

Cholecystectomy after endoscopic sphincterotomy (ES) is associated with improved outcomes compared to ES alone, however randomized trials have included mainly fit surgical candidates. Our objective was to assess the impact of cholecystectomy after ES among elderly patients, in whom the perceived risks of surgery may be increased and the prevailing bias may be to defer cholecystectomy.

METHODS

We performed adjusted analyses comparing clinical outcomes in patients ≥65 years of age who did and did not undergo follow-up cholecystectomy after endoscopic sphincterotomy for choledocholithiasis, ascending cholangitis, or gallstone pancreatitis. We also compared adverse events between the two groups.

RESULTS

In the ES alone group, 39.3% of patients experienced a recurrent complication compared with 18.0% in the ES and cholecystectomy group. After adjusting for comorbidities using multivariable regression, cholecystectomy in addition to ES was associated with a reduced risk of recurrent choledocholithiasis (OR 0.38, 95%CI 0.34-0.42, P<0.001), ascending cholangitis (OR 0.28, 95%CI 0.23-0.34, P<0.001), and gallstone pancreatitis (OR 0.35, 95%CI 0.24-0.49, P<0.001) compared to ES alone. This benefit was preserved after propensity score adjustment, in patients ≥75 years of age, and in those with major comorbidities including cancer, heart failure, and liver disease. Serious post-operative complications such as myocardial infarction, pulmonary embolism, and pneumonia were not more common in the cholecystectomy group.

CONCLUSIONS

Among older patients, including those with serious comorbidities, cholecystectomy after endoscopic sphincterotomy was associated with a significant and clinically important reduction in recurrent complications compared to sphincterotomy alone. This benefit did not appear to be outweighed by surgical complications, highlighting the importance of cholecystectomy, even in elderly patients whose lifespans may be limited by unrelated conditions.

Glucuronides in the gut: Sugar-driven symbioses between microbe and host

The intestinal milieu is astonishingly complex and home to a constantly changing mixture of small and large molecules, along with an abundance of bacteria, viral particles, and eukaryotic cells. Such complexity makes it difficult to develop testable molecular hypotheses regarding host-microbe interactions. Fortunately, mammals and their associated gastrointestinal (GI) microbes contain complementary systems that are ideally suited for mechanistic studies. Mammalian systems inactivate endobiotic and xenobiotic compounds by linking them to a glucuronic acid sugar for GI excretion. In the GI tract, the microbiota express β-glucuronidase enzymes that remove the glucuronic acid as a carbon source, effectively reversing the actions of mammalian inactivation. Thus, by probing the actions of microbial β-glucuronidases, and by understanding which substrate glucuronides they process, molecular insights into mammalian-microbial symbioses may be revealed amid the complexity of the intestinal tract. Here, we focus on glucuronides in the gut and the microbial proteins that process them.

Proton pump inhibitor is a risk factor for recurrence of common bile duct stones after endoscopic sphincterotomy - propensity score matching analysis

Background and study aims Recurrence of common bile duct stones (CBDS) in patients treated with endoscopic sphincterotomy (ES) can lead to deterioration in their quality of life. Although the pathology and related factors are unclear, we speculated that proton pump inhibiter (PPI) administration increases the risk of CBDS recurrence by altering the bacterial mixture in the bile duct. Patients and methods The primary endpoint of this retrospective study was recurrence-free period. Several independent variables considered to have a relationship with CBDS recurrence including PPI use were analyzed using a COX proportional hazard model, with potential risk factors then evaluated by propensity score matching analysis. Results A total of 219 patients were analyzed, with CBDS recurrence found in 44. Analysis of variables using a COX proportional hazard model demonstrated that use of PPIs and ursodeoxycholic acid (UDCA), as well as the presence of periampullary diverticula (PD) each had a hazard ratio (HR) value greater than 1 (HR 2.2, P = 0.007; HR 2.0, P = 0.02; HR 1.9, P = 0.07; respectively). Furthermore, propensity score matching analysis revealed that the mean recurrence-free period in the oral PPI cohort was significantly shorter as compared with the non-PPI cohort (1613 vs. 2587 days, P = 0.014). In contrast, neither UDCA administration nor PD presence was found to be a significant factor in that analysis (1557 vs. 1654 days, P = 0.508; 1169 vs. 2011 days, P = 0.121; respectively). Conclusion Our results showed that oral PPI administration is a risk factor for CBDS recurrence in patients who undergo ES.

A comparative study of mud-like and coralliform calcium carbonate gallbladder stones

To gain insight to underlying mechanism of the formation of calcium carbonate (CaCO₃ ) gallbladder stones, we did comparative study of stones with mud appearance and those with coralliform appearance. A total of 93 gallbladder stones with mud appearance and 50 stones with coralliform appearance were analyzed. The appearance, color, texture, and the detection of Clonorchis sinensis eggs by microscopic examination were compared between the two groups. Then, the material compositions of stones were analyzed using Fourier Transform Infrared spectroscopy and the spectrogram characteristics were compared. Moreover, microstructure characteristics of the two kinds of stones were observed and compared with Scanning Electron Microscopy. Mud-like gallbladder stones were mainly earthy yellow or brown with brittle or soft texture, while coralliform stones were mainly black with extremely hard texture, the differences between the two groups was significant (p < .05). The analytic results of FTIR spectroscopy showed that 95.7% (89/93) of the mud-like gallbladder stones were CaCO₃ stones, and mainly aragonite; while all of the coralliform stones were CaCO₃ stones, and mainly calcite (p < .05). Meanwhile, microscopic examination indicated that the detection rate of Clonorchis sinensis eggs in mud-like CaCO₃ stones was lower than that in coralliform CaCO₃ stones (p < .05), and that in aragonite CaCO₃ stones was lower than that in calcite CaCO₃ stones(p < .05). Mud-like CaCO₃ stones mainly happened to patients with cystic duct obstruction. Clonorchis sinensis infection was mainly associated with coralliform (calcite) CaCO₃ stones. Cystic duct obstruction was mainly associated with mud-like (aragonite) CaCO₃ stones.

Is Routine Prophylactic Cholecystectomy Necessary During Gastrectomy for Gastric Cancer?

BACKGROUND

Performing routine prophylactic cholecystectomy during gastrectomy in gastric cancer patients has been controversial. The frequency of cholelithiasis, cholecystitis, and cholangitis after gastrectomy has not been reported for large patient populations, so we carried out this retrospective study to aid the assessment of the necessity for prophylactic cholecystectomy.

METHODS

This retrospective study reviewed 969 patients with gastric cancer who underwent distal gastrectomies with Billroth I reconstructions (DG) or total gastrectomies with Roux-en-Y reconstructions (TG), preserving the gallbladder, between January 2000 and May 2012. Risk factors for cholelithiasis, cholecystitis, and cholangitis after gastrectomy were evaluated using logistic regression analysis.

RESULTS

The median follow-up period after gastrectomy was 48 months (range 12-159 months). After gastrectomy, cholelithiasis occurred in 6.1% (59/969) patients and cholecystitis and/or cholangitis occurred in 1.2% (12/969) patients. The method used for gastrectomy was an independent risk factor for both cholelithiasis (TG/DG: OR (95%CI): 1.900 (1.114-3.240), p = 0.018) and cholecystitis and/or cholangitis (TG/DG: OR (95%CI): 8.325 (1.814-38.197), p = 0.006). In patients who developed cholelithiasis, the incidence of cholecystitis and/or cholangitis was 31.3% (10/32) after TG, but only 7.4% after DG.

CONCLUSIONS

Prophylactic cholecystectomy may be unnecessary in distal gastrectomy with Billroth I reconstruction.

Extracorporeal abdominal massage may help prevent recurrent bile duct stones after endoscopic sphincterotomy

Endoscopic sphincterotomy (EST) is effective, but recurrent bile duct stones are a common late complication. Because there are still no effective therapies for preventing this complication, some patients have experienced bile duct stone recurrence many times. We describe herein a method of abdominal massage to treat patients with prior cholecystectomy who have experienced recurrence of bile duct stones.

Analytic Reviews : Nonsurgical Alternatives in the Management of Gallstones

Until recently, the only therapeutic option for patients with symptomatic gallstones was surgery. However, sev eral new and innovative nonsurgical approaches are cur rently available, including oral dissolution therapy with the bile salts, ursodeoxycholic and chenodeoxycholic acids, instillation of liquid solvents such as methyl tert- butyl ether directly into the gallbladder or the common bile duct, and extracorporeal shock-wave lithotripsy. We review the role of each of these methods in the management of patients with gallstones as well as the epidemiology, pathogenesis, natural history, and radi ological characteristics of gallstones, all important con siderations when choosing appropriate treatment for the individual patient.

Influence of the Biliary System on Biliary Bacteria Revealed by Bacterial Communities of the Human Biliary and Upper Digestive Tracts

Biliary bacteria have been implicated in gallstone pathogenesis, though a clear understanding of their composition and source is lacking. Moreover, the effects of the biliary environment, which is known to be generally hostile to most bacteria, on biliary bacteria are unclear. Here, we investigated the bacterial communities of the biliary tract, duodenum, stomach, and oral cavity from six gallstone patients by using 16S rRNA amplicon sequencing. We found that all observed biliary bacteria were detectable in the upper digestive tract. The biliary microbiota had a comparatively higher similarity with the duodenal microbiota, versus those of the other regions, but with a reduced diversity. Although the majority of identified bacteria were greatly diminished in bile samples, three Enterobacteriaceae genera (Escherichia, Klebsiella, and an unclassified genus) and Pyramidobacter were abundant in bile. Predictive functional analysis indicated enhanced abilities of environmental information processing and cell motility of biliary bacteria. Our study provides evidence for the potential source of biliary bacteria, and illustrates the influence of the biliary system on biliary bacterial communities.

Ursodeoxycholic acid after bile duct stone removal and risk factors for recurrence: a randomized trial

BACKGROUND

Currently, no established pharmacologic treatment exists for the prevention of recurrent common bile duct (CBD) stones.

METHODS

Here, we present a multi-center randomized trial that compared the CBD recurrence rate after bile duct stone removal between patients given ursodeoxycholic acid (UDCA) and the untreated group. A total of 36 patients were randomly assigned to either the UDCA (n = 15) or the untreated group (n = 21). The primary end-point was the recurrence rate of CBD stones.

RESULTS

The recurrence rate of CBD stones was 6.6% in the UDCA group and 18.6% in the untreated group (P = 0.171). A multivariate analysis found that not receiving UDCA was an independent risk factor for stone recurrence. The recurrence rates of CBD stones did not differ by sex, past history of cholecystectomy, or the presence of gallstones.

CONCLUSIONS

Our findings indicate that UDCA may be a novel treatment strategy to prevent the recurrence of CBD stones. However, further evaluation of UDCA in a larger number of subjects will be required to confirm the applicability of these results.