Gut Microbiota Composition of Biliary Atresia Patients Before Kasai Portoenterostomy Associates With Long-term Outcome

Biliary atresia: the role of gut microbiome, and microbial metabolites

Biliary atresia (BA) is a progressive fibroinflammatory disease affecting both the extrahepatic and intrahepatic bile ducts, potentially leading to chronic cholestasis and biliary cirrhosis. Despite its prevalence, the exact mechanisms behind BA development remain incompletely understood. Recent research suggests that the gut microbiota and its metabolites may play significant roles in BA development. This paper offers a comprehensive review of the changing characteristics of gut microbiota and their metabolites at different stages of BA in children. It discusses their influence on the host's inflammatory response, immune system, and bile acid metabolism. The review also explores the potential of gut microbiota and metabolites as a therapeutic target for BA, with interventions like butyrate and gut microbiota preparations showing promise in alleviating BA symptoms. While progress has been made, further research is necessary to untangle the complex interactions between gut microbiota and BA, paving the way for more effective prevention and treatment strategies for this challenging condition.

Gut Bifidobacterium longum is associated with better native liver survival in patients with biliary atresia

Background & Aims

The gut microbiome plays an important role in liver diseases, but its specific impact on biliary atresia (BA) remains to be explored. We aimed to investigate the microbial signature in the early life of patients with BA and to analyze its influence on long-term outcomes.

Methods

Fecal samples (n = 42) were collected from infants with BA before and after Kasai portoenterostomy (KPE). The stool microbiota was analyzed using 16S rRNA next-generation sequencing and compared with that of age-matched healthy controls (HCs). Shotgun metagenomic sequencing analysis was employed to confirm the bacterial composition in 10 fecal samples before KPE. The correlation of the microbiome signature with liver function and long-term outcomes was assessed.

Results

In the 16S rRNA next-generation sequencing analysis of fecal microbiota, the alpha and beta diversity analyses revealed significant differences between HCs and patients with BA before and after KPE. The difference in microbial composition analyzed by linear discriminant analysis and random forest classification revealed that the abundance of Bifidobacterium longum (B. longum) was significantly lower in patients before and after KPE than in HCs. The abundance of B. longum was negatively correlated with the gamma-glutamyltransferase level after KPE (p <0.05). Patients with early detectable B. longum had significantly lower total and direct bilirubin 3 months after KPE (p <0.005) and had a significantly lower liver transplantation rate (hazard ratio: 0.16, 95% CI 0.03-0.83, p = 0.029). Shotgun metagenomic sequencing also revealed that patients with BA and detectable B. longum had reduced total and direct bilirubin after KPE.

Conclusion

The gut microbiome of patients with BA differed from that of HCs, with a notable abundance of B. longum in early infancy correlating with better long-term outcomes.

Impact and implications

Bifidobacterium longum (B. longum) is a beneficial bacterium commonly found in the human gut. It has been studied for its potential impacts on various health conditions. In patients with biliary atresia, we found that a greater abundance of B. longum in the fecal microbiome is associated with improved clinical outcomes. This suggests that early colonization and increasing B. longum levels in the gut could be a therapeutic strategy to improve the prognosis of patients with biliary atresia.

Alterations of gut microbiota in infants with biliary atresia identified by 16S rRNA-sequencing

BACKGROUND

Biliary atresia (BA) is a severe neonatal disease with progressive intra- and extra-hepatic bile ducts inflammation and hepatic fibrosis. Characterization of gut microbiome profiles in infants with biliary atresia can provide valuable information and potential disease biomarkers. Our study aims to explore the relationship between gut microbiota and biliary atresia.

METHODS

16 S ribosomal RNA (rRNA) gene sequencing was carried out to identify the differences in composition and diversity of gut microbiota between infants with BA and healthy subjects. A total of 31 infants with biliary atresia and 20 healthy subjects were recruited.

RESULTS

The composition of gut microbiota in BA group was significantly different with the normal control group (P < 0.05) and the abundance ratio of Klebsiella/Bifidobacterium showed great potential for identification of BA (P < 0.01). In addition, the differential bacterial taxa were involved in lipid and vitamins metabolism.

CONCLUSION

Our results could provide potential non-invasive biomarker for identification of biliary atresia and contribute to the treatment in terms of ameliorating microbiota dysbiosis.

Diagnostic and prognostic value of the gut microbiota and its metabolite butyrate in children with biliary atresia

PURPOSE

To determine the prevalent microbiological profile of biliary atresia (BA) patients at the time of its occurrence by studying their intestinal flora.

METHODS

A total of 118 gut microbiota samples from three groups of 43 BA patients, 33 disease controls (DC) with other cholestatic diseases and 42 healthy controls (HC), were analyzed by deep mining of public data. Subsequently, a total of 23 fecal samples from three groups of clinically collected patients (11 BA, 6 DC and 6 HC) were sequenced for 16S rRNA gene amplification and analyzed for serum butyrate (BU) level by liquid chromatography.

RESULTS

Taxonomic analysis revealed significant differences in the composition of the intestinal microbiota between BA patients and controls, with a reduction in diversity and a higher abundance of Proteobacteria, Streptococcus and Lactobacillus in the BA group. Database and clinical data analyses concluded that Streptococcus/Bacteroides (AUC = 0.9035, 95% CI 0.8347-0.9722, P < 0.0001) or Streptococcus/Eggerthella (AUC = 0.8333, 95% CI 0.6340-1.000, P = 0.027) was the best microbiota to differentiate between BA and DC. Serum butyrate levels were low in the BA and DC groups and differed from the HC group (P = 0.01, P = 0.04). Butyrate levels in BA were negatively correlated with jaundice clearance and cholangitis, but not statistically significant.

CONCLUSIONS

Our study reveals changes in the composition of the gut microbiota in BA, especially the butyrate-producing microbiota, and suggests the potential for using gut microbiota as a noninvasive diagnostic benefit for BA. Low levels of serum butyrate in BA may indicate a poor prognosis.

Bacterial translocation markers and toll-like receptors in biliary atresia following successful portoenterostomy

AIM

The gut-liver axis may contribute to pathophysiology of cholestatic liver disorders like biliary atresia (BA) by bacterial translocation (BT). Toll-like receptors (TLR) are pattern recognition receptors known to activate innate immunity and secretion of inflammatory cytokines. Herein, we examined BT-associated biomarkers and TLRs in relation to liver injury after successful portoenterostomy (SPE) in BA.

METHODS

Serum levels of lipopolysaccharide-binding protein (LBP), CD14, LAL, TNF-α, IL-6 and FABP2 along with liver expression of TLRs (TLR1, TLR4, TLR7 and TLR9), LBP and CD14 were measured during median 4.9 (1.7-10.6) years follow-up after SPE in 45 BA patients.

RESULTS

Serum LBP, CD14, TNF-α and IL-6 all increased after SPE whereas LAL and FABP-2 remained unchanged. Serum LBP correlated positively with CD14 and markers of hepatocyte injury and cholestasis, but not with Metavir fibrosis stage, transcriptional markers for fibrosis (ACTA2) or ductular reaction. Serum CD14 concentration was significantly higher in patients with portal hypertension than without. While liver expression of TLR4 and LBP remained low, TLR7 and TLR1 showed marked BA-specific increases, and TLR7 correlated with Metavir fibrosis stage and ACTA2.

CONCLUSION

BT does not seem to play a significant role in liver injury after SPE in our series of BA patients.

Customized Postoperative Therapy Improves Bile Drainage in Biliary Atresia: A Single Center Preliminary Report

BACKGROUND

Controversies in management of biliary atresia (BA) after hepatoportoenterostomy (HPE) lead to variable treatment protocols. We implemented standardized medical management after HPE, customizing the use of antibiotics and corticosteroids based on patient-specific factors.

METHODS

In this retrospective analysis, 20 consecutive infants underwent HPE for BA and were compared to a historical cohort. Analysis of successful biliary drainage 3 months after HPE (defined as serum total bilirubin <2 mg/dL) was the primary endpoint; survival with native liver at 2 years was the secondary endpoint.

RESULTS

Sixteen of 20 (80%) infants had successful bile drainage, compared to 8 of 20 (40%) infants in the historical cohort (P = 0.0225). Sixteen of 20 patients in the new protocol have reached 2 years of age or required liver transplantation. Among the sixteen, 11 (68.8%) are alive with native livers versus 10 of 20 (50%) in the historical cohort (P = 0.0970).

CONCLUSION

This preliminary report suggests the potential benefit of tailored use of postoperative antibiotics and corticosteroids in improving biliary drainage after HPE.

LEVEL OF EVIDENCE

III.

The influence of liver transplantation on the interplay between gut microbiome and bile acid homeostasis in children with biliary atresia

BACKGROUND

Biliary atresia (BA) causes neonatal cholestasis and rapidly progresses into cirrhosis if left untreated. Kasai portoenterostomy may delay cirrhosis. BA remains among the most common indications for liver transplantation (LT) during childhood. Liver function and gut microbiome are interconnected. Disturbed liver function and enterohepatic signaling influence microbial diversity. We, herein, investigate the impact of LT and reestablishment of bile flow on gut microbiome-bile acid homeostasis in children with BA before (pre, n = 10), 3 months (post3m, n = 12), 12 months (post12m, n = 9), and more than 24 months (post24 + m, n = 12) after LT.

METHODS

We analyzed the intestinal microbiome of BA patients before and after LT by 16S-rRNA-sequencing and bioinformatics analyses, and serum primary and secondary bile acid levels.

RESULTS

The gut microbiome in BA patients exhibits a markedly reduced alpha diversity in pre (p = 0.015) and post3m group (p = 0.044), and approximated healthy control groups at later timepoints post12m (p = 1.0) and post24 + m (p = 0.74). Beta diversity analysis showed overall community structure similarities of pre and post3m (p = 0.675), but both differed from the post24 + m (p < 0.001). Longitudinal analysis of the composition of the gut microbiome revealed the Klebsiella genus to show increased abundance in the post24 + m group compared with an age-matched control (p = 0.029). Secondary bile acid production increased 2+ years after LT (p = 0.03). Multivariable associations of microbial communities and clinical metadata reveal several significant associations of microbial genera with tacrolimus and mycophenolate mofetil-based immunosuppressive regimens.

CONCLUSIONS

In children with BA, the gut microbiome shows strongly reduced diversity before and shortly after LT, and approximates healthy controls at later timepoints. Changes in diversity correlate with altered secondary bile acid synthesis at 2+ years and with the selection of different immunosuppressants.

Biliatresone: progress in biliary atresia study

BACKGROUND

Biliary atresia (BA) is one of the main causes of neonatal end-stage liver disease. Without timely diagnosis and treatment, most children with BA will develop irreversible liver fibrosis within the first two months. While current theorized causes of BA include viral infection, immune disorders, and genetic defects, the comprehensive etiology is still largely unknown. Recently, biliatresone attracted much interest for its ability to induce BA in both zebrafish and mice, so we summarized the latest progress of biliatresone research in BA and tried to answer the question of whether it could provide further clues to the etiology of human BA.

DATA SOURCES

We conducted a PubMed search for any published articles related to the topic using search terms including "biliary atresia", "biliatresone", "GSH", and "HSP90". Relevant data were extracted from the original text or supplementary materials of the corresponding articles.

RESULTS

Biliatresone had shown its unique toxicity in multiple species such as zebrafish and mice, and pathogenic factors involved included glutathione (GSH), heat shock protein 90 (HSP90) and the related pathways. In combination with epidemiological evidence and recent studies on the intestinal flora in biliary atresia, a new pathogenic hypothesis that the occurrence of biliary atresia is partly due to biliatresone or its structure-like compounds depositing in human body via vegetables or/and the altered intestinal flora structure can be tentatively established.

CONCLUSIONS

Based on the existing evidence, we emphasized that GSH and HSP90 are involved in the development of BA, and the maternal diet, especially higher vegetable intake of Asian women of childbearing age, accompanied by the altered intestinal flora structure, may contribute to the occurrence of biliary atresia and the higher incidence in the Asia group. However, the evidence from large sample epidemiological research is necessary.

Biliary Atresia in Adolescence and Adult Life: Medical, Surgical and Psychological Aspects

Prior to 1955, when Morio Kasai first performed the hepatic portoenterostomy procedure which now bears his name, Biliary atresia (BA) was a uniformly fatal disease. Both the Kasai procedure and liver transplantation have markedly improved the outlook for infants with this condition. Although long-term survival with native liver occurs in the minority, survival rates post liver transplantation are high. Most young people born with BA will now survive into adulthood but their ongoing requirements for health care will necessitate their transition from a family-centred paediatric service to a patient-centred adult service. Despite a rapid growth in transition services over recent years and progress in transitional care, transition from paediatric to adult services is still a risk for poor clinical and psychosocial outcomes and increased health care costs. Adult hepatologists should be aware of the clinical management and complications of biliary atresia and the long-term consequences of liver transplantation in childhood. Survivors of childhood illness require a different approach to that for young adults presenting after 18 years of age with careful consideration of their emotional, social, and sexual health. They need to understand the risks of non-adherence, both for clinic appointments and medication, as well as the implications for graft loss. Developing adequate transitional care for these young people is based on effective collaboration at the paediatric-adult interface and is a major challenge for paediatric and adult providers alike in the 21st century. This entails education for patients and adult physicians in order to familiarise them with the long-term complications, in particular for those surviving with their native liver and the timing of consideration of liver transplantation if required. This article focusses on the outcome for children with biliary atresia who survive into adolescence and adult life with considerations on their current management and prognosis.

What Makes A "Successful" Kasai Portoenterostomy "Unsuccessful"?

OBJECTIVES

Clearance of jaundice (CoJ) is the first key objective of Kasai portoenterostomy (KPE) for biliary atresia (BA) and its achievement is by far the best index of long-term prognosis. We sought to identify the reasons for failure [subsequent liver transplant (LT)] in this cohort.

METHODS

Review of single-center prospective BA database. Successful KPE was defined by achieving a postoperative bilirubin of ≤20 µmol/L. Pre-KPE and post-KPE variables were identified together with a multivariate logistic regression model to identify those observable at 3 months post-KPE. Data are quoted as median (range). A P value of ≤0.05 was significant.

RESULTS

One hundred thirty-five infants underwent KPE between January 2012 and December 2018, of which 90 (67%) achieved CoJ. From these 20 (22%) (Cohort A) underwent LT with the remainder continuing with native liver (Cohort B) (median follow-up of 4.15 years). There was no difference in age at KPE ( P = 0.41), APRi (aspartate aminotransferase-to-platelet ratio) ( P = 0.07), associated anomalies ( P = 0.7), and cytomegalovirus status ( P = 0.7) between the 2 groups. Postoperatively, both cholangitis [any episode, 18/20 (90%) vs 15/70 (21%); P < 0.0001] and portal hypertension (PHT) [gastrointestinal (GI) bleed, 10/20 (50%) vs 2/70 (2.8%); P < 0.0001] were significantly more common in cohort A. Univariate analysis showed that the most significant predictive values at 3 months for LT by 2 years were high APRi, bilirubin, international normalized ratio, and ultrasound (US)-detected ascites with multivariate logistic modeling confirming these variables with predictive values of r2 = 0.79, AUROC = 0.98.

CONCLUSIONS

Failure is not preordained at KPE but due to recurrent cholangitis and/or symptoms of PHT.