The viral association of neonatal cholestasis in Sweden: a possible link between cytomegalovirus infection and extrahepatic biliary atresia

Diseases of bile duct in children

Several diseases originate from bile duct pathology. Despite studies on these diseases, certain etiologies of some of them still cannot be concluded. The most common disease of the bile duct in newborns is biliary atresia, whose prognosis varies according to the age of surgical correction. Other diseases such as Alagille syndrome, inspissated bile duct syndrome, and choledochal cysts are also time-sensitive because they can cause severe liver damage due to obstruction. The majority of these diseases present with cholestatic jaundice in the newborn or infant period, which is quite difficult to differentiate regarding clinical acumen and initial investigations. Intraoperative cholangiography is potentially necessary to make an accurate diagnosis, and further treatment will be performed synchronously or planned as findings suggest. This article provides a concise review of bile duct diseases, with interesting cases.

Pediatric Cholestatic Diseases: Common and Unique Pathogenic Mechanisms

Cholestasis is the predominate feature of many pediatric hepatobiliary diseases. The physiologic flow of bile requires multiple complex processes working in concert. Bile acid (BA) synthesis and excretion, the formation and flow of bile, and the enterohepatic reuptake of BAs all function to maintain the circulation of BAs, a key molecule in lipid digestion, metabolic and cellular signaling, and, as discussed in the review, a crucial mediator in the pathogenesis of cholestasis. Disruption of one or several of these steps can result in the accumulation of toxic BAs in bile ducts and hepatocytes leading to inflammation, fibrosis, and, over time, biliary and hepatic cirrhosis. Biliary atresia, progressive familial intrahepatic cholestasis, primary sclerosing cholangitis, and Alagille syndrome are four of the most common pediatric cholestatic conditions. Through understanding the commonalities and differences in these diseases, the important cellular mechanistic underpinnings of cholestasis can be greater appreciated.

Cytomegalovirus in biliary atresia is associated with increased pretransplant death, but not decreased native liver survival

BACKGROUND

Biliary atresia (BA) is likely caused by a common phenotypic response to various triggers; one proposed trigger, cytomegalovirus (CMV), may lead to worse outcomes. The aim of this study was to determine the severity of disease and pretransplant outcomes of infants with BA, who have evidence of CMV (CMV+) at diagnosis compared with CMV-negative (CMV-) infants.

METHODS

The study used data and biospecimens from the Childhood Liver Disease Research Network PROBE study of cholestatic infants. Plasma obtained at the time of hepatic portoenterostomy (HPE) of 249 infants with BA was tested for CMV by DNA-PCR and CMV-IgM. Comparisons between CMV+ and CMV- infants were made using Wilcoxon rank sum, Student t test, chi-square, or Fisher exact test. Native liver survival (NLS) outcomes were analyzed using Kaplan-Meier and Cox regression adjusting for age at HPE; pretransplant patient survival outcomes were analyzed using a competing risk model and adjusting for age at HPE.

RESULTS

CMV+ infants (n = 29, 12%) underwent HPE later (67.8±13.6 d vs. 55.1±18.5 d, p = 0.0005) and had higher baseline alkaline phosphatase and aminotransferases. There was no difference between groups in jaundice clearance or NLS. The subdistribution HR of pretransplant death for CMV+ infants adjusted for age at HPE was 3.8 (p = 0.034).

CONCLUSIONS

CMV infection at the time of HPE in infants with BA is not associated with worse NLS despite the association with worse liver injury, older age at HPE, and increased risk of pretransplant death adjusted for age at HPE. Continued evaluation of the consequences of CMV infection and the effects of antiviral treatment should be explored.

Advances in understanding of biliary atresia pathogenesis and progression - a riddle wrapped in a mystery inside an enigma

INTRODUCTION

Biliary atresia is a potentially fatal condition of the bile ducts - both intra- and extrahepatic, for which we have no cure. Though principally a cholestatic condition, much of its pathology stems from its tendency to aggressively induce liver fibrosis and ultimately cirrhosis, only partially restrained by the portoenterostomy.

AREAS COVERED

This review is based on the current literature exploring the heterogeneous nature of biliary atresia. Thus, there are various phenotypes or variants of biliary atresia, each potentially with different etiological backgrounds caused by a number of hypothetical pathological mechanisms thought to be important in the genesis of the condition. Search methodology: the review (Oct. - Nov. 2022) is based on a search of PubMed (NLM) using main keyword 'biliary atresia' with supplementary searches using 'fibrosis'; 'inflammation'; 'BASM'; 'genetics'; 'surgery'; 'experimental'; 'etiology'; 'virology'; 'cases'; and 'syndromes.'

EXPERT OPINION

Future developments will be made on matching clinical variants with a more distinct pathophysiological discrimination and those pathways linking the initial cholestatic phase of biliary atresia to the early stages of fibrosis.

Incidence and antiviral treatment of cytomegalovirus infection in infants with biliary atresia

PURPOSE

Patients with biliary atresia (BA) and cytomegalovirus (CMV) infection may have poorer outcomes after Kasai portoenterostomy (KPE) than uninfected patients, suggesting a rationale for antiviral treatment (AVT). We aimed to describe the incidence of CMV infection and of AVT in BA patients, and to detect any differences between infected and uninfected patients to conclude if AVT is of use.

METHODS

Data on BA patients who underwent KPE 2004-2020 were retrospectively collected, and the outcome was analyzed with regard to CMV status.

RESULTS

Fifteen out of forty-six (33%) BA patients had signs of ongoing CMV infection. They did not differ significantly from the CMV-negative patients regarding rate of prematurity, birth weight, or biochemical markers but were slightly older at KPE. All patients received steroids postoperatively and all patients with ongoing CMV infection received AVT with very good effect on viremia and without major side effects. The AVT consisted of oral valganciclovir (10-40 (- 58) mg/kg/d) or intravenous ganciclovir (5.3-11 mg/kg/d).

CONCLUSION

Ongoing CMV infection is common in this group of patients. The viremia can effectively be treated with AVT without any major side effects. Larger, randomized studies are needed to clarify the possible effect on clinical outcome.

The Impact of a CMV Infection on the Expression of Selected Immunological Parameters in Liver Tissue in Children with Biliary Atresia

The pathogenesis of biliary atresia (BA) is still not clear. The aim of this study was to evaluate the expression of selected immunological parameters in liver tissue in BA children based on CMV/EBV infection status. Eight of thirty-one children with newly diagnosed BA were included in this prospective study and assigned to two groups (I with active infection, II without active or past infection). All studies were performed on surgical liver biopsies. To visualize CD8+ T cells and CD56 expression, immunohistochemical staining was performed. The viral genetic material in the studied groups was not found, but CMV infection significantly affected the number of CD8+ lymphocytes in both the portal area and the bile ducts. The average number of CD8+ cells per mm² of portal area in Groups I and II was 335 and 200 (p = 0.002). The average number of these cellsthat infiltrated the epithelium of the bile duct per mm² in Group I and II was 0.73 and 0.37 (p = 0.0003), respectively. Expression of CD56 in the bile ducts corresponded to the intensity of the inflammatory infiltrate of CD8+ cells. Our results suggest that active CMV infection induces an increased infiltration of CD8+ lymphocytes, which could play a role in BA immunopathogenesis. Increased CD56 expression can be a sign of a newly formed bile structure often without lumen, suggesting inhibition of the maturation process in BA.

A Comparative Study Between Cytomegalovirus Immunoglobulin M-Positive and CMV Immunoglobulin M-Negative Biliary Atresia in Infants Attending a Tertiary Care Hospital in Bangladesh

PURPOSE

Perinatal cytomegalovirus (CMV) infection can lead to biliary atresia (BA) in different entities. This study aimed to compare the clinical, hematological, biochemical, and histological features of infants with BA based on their CMV immunoglobulin M (IgM) status at presentation.

METHODS

This cross-sectional descriptive study was carried out between January 2019 and June 2020 at the Department of Pediatric Gastroenterology and Nutrition at the Bangabandhu Sheikh Mujib Medical University (BSMMU) in Dhaka. Forty-three patients with BA were selected purposively and categorized into either the CMV IgM-positive or CMV IgM-negative BA group. Categorical variables were compared using Fisher's exact test and chi-square tests, while the Student's t-test and Mann-Whitney U-test were used to compare continuous variables. For all statistical tests, a p-value <0.05 was considered statistically significant.

RESULTS

Thirty-three (76.7%) of the cases were between 2 and 3 months of age on admission. The clinical, hematological, and biochemical parameters did not differ significantly between the CMV IgM-positive and CMV IgM-negative BA groups. Most (50.0%) of the CMV IgM-positive cases had fibrosis stage F2, while 43.5% of the CMV IgM-negative cases had fibrosis stage F3, with no significant difference between the groups (p=0.391).

CONCLUSION

Our data shows no significant distinction between CMV IgM-positive and CMV IgM-negative BA, suggesting that CMV does not contribute to BA pathogenesis.

[Overview of Biliary Atresia]

Biliary atresia is a progressive, idiopathic, obliterative disease of the extrahepatic biliary tree that presents with biliary obstruction in the neonatal period. It is the most common indication for liver transplantation in children. If untreated, progressive liver cirrhosis leads to death by two years of age. Nowadays, more than 90% of biliary atresia patients survive into adulthood with the development of Kasai portoenterostomy and liver transplantation technology. Early diagnosis is critical since the success rate of the Kasai portoenterostomy decreases with time. This study comprehensively reviews the recent advances in the etiology, classification, prevalence, clinical manifestations, treatment, and prognosis of biliary atresia.

Biliary atresia and congenital disorders of the extrahepatic bile ducts

Biliary atresia (BA) and choledochal cysts are diseases of the intrahepatic and extrahepatic biliary tree. While their exact etiopathogeneses are not known, they should be treated promptly due to the potential for irreversible parenchymal liver disease. A diagnosis of BA may be easy or complicated, but should not be delayed. BA is always treated surgically, and performing the surgery before the age of 2 mo greatly increases its effectiveness and extends the time until the need for liver transplantation arises. While the more common types of choledochal cysts require surgical treatment, some can be treated with endoscopic retrograde cholangiopancreatography. Choledochal cysts may cause recurrent cholangitis and the potential for malignancy should not be ignored.

Incidence, Impact and Treatment of Ongoing CMV Infection in Patients with Biliary Atresia in Four European Centres

Cytomegalovirus (CMV) infection has been suggested to be of importance for the development and outcome of biliary atresia (BA). However, most data are only available from single centre studies. We retrospectively collected data on rates, outcomes, and treatments for ongoing CMV infection at the time of Kasai portoenterostomy (KPE) from four different tertiary centres in Europe. The rate of ongoing CMV infection varied between 10–32% in the four centres. CMV positive patients were significantly older and had higher levels of several liver biochemistries at the time of KPE (p < 0.05 for all comparisons). In the largest centre, CMV infection was more common in non-Caucasians, and CMV infected patients had poorer long-term survival with native liver than CMV negative patients (p = 0.0001). In contrast, survival with native liver in the subgroup of CMV infected patients who had received antiviral treatment was similar to the CMV negative group. We conclude that ongoing CMV infection at the time of KPE occurs in a significant proportion of BA patients and that these patients seem to differ from CMV negative patients regarding age and biochemistry at the time of KPE as well as long-term survival with native liver. The latter difference may be reduced by antiviral treatment, but randomized, controlled trials are needed before such treatment can be recommended routinely.

Biliary atresia in a neonate with a history of COVID-19: A case report

Introduction and importance

Biliary Atresia is the progressive destruction of the neonatal intra- and extra- hepatic bile ducts. The novel coronavirus has shown dramatic hepatic tropism, and patients experiencing liver injury appear to have worse outcomes. We present the first documented case of a neonate diagnosed with Biliary Atresia and a prior history of COVID-19.

Case presentation

A two-month-old female presented with increasing scleral icterus. Her laboratory testing demonstrated direct hyperbilirubinemia, with elevated alkaline phosphatase and increased ALT. She tested positive for COVID-19 at that time, requiring a two-week quarantine during which time she did not develop respiratory symptoms. Two weeks later, she presented to the hospital with emesis and an evaluation concerning for biliary atresia. She ultimately underwent a Kasai repair and recovered well with no significant post-operative complications.

Clinical discussion

Biliary Atresia is a heterogenous disease of unknown etiology, though viral triggers are suggested to contribute. COVID-19 disease is frequently associated with liver damage, though its relationship to Biliary Atresia is unexplored. We present a case of a neonate who contracted COVID-19 infection, and subsequently developed biliary atresia.

Conclusion

Considering this child's concurrent COVID-19 infection, viral mediated hepatic and biliary inflammation may have contributed to the development of Biliary Atresia in this case. The proposed relationship requires additional investigation but may suggest value in COVID-19 testing for patients presenting with Biliary Atresia.

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Biliary atresia results in a fibrosclerosing, obliterative cholangiopathy

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Several viruses may play a role in the development of biliary atresia

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The novel coronavirus SARS-CoV-2 has shown dramatic hepatic tropism

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It is unknown if COVID-19 disease is related to the development of biliary atresia

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We present the first case of biliary atresia after diagnosis of COVID-19 disease

A joint transcriptional regulatory network and protein activity inference analysis identifies clinically associated master regulators for biliary atresia

Biliary atresia (BA) is a devastating cholangiopathy in neonate. Transcription factors (TFs), a type of master regulators in biological processes and diseases, have been implicated in pathogenesis of BA. However, a global view of TFs and how they link to clinical presentations remain explored. Here, we perform a joint transcriptional regulatory network and protein activity inference analysis in order to investigate transcription factor activity in BA. By integration of three independent human BA liver transcriptome datasets, we identify 22 common master regulators, with 14 activated- and 8 repressed TFs. Gene targets of activated TFs are enriched in biological processes of SMAD, NF-kappaB and TGF-beta, while those of repressed TFs are related to lipid metabolism. Mining the clinical association of TFs, we identify inflammation-, fibrosis- and survival associated TFs. In particular, ZNF14 is predictive of poor survival and advanced live fibrosis. Supporting this observation, ZNF14 is positively correlated with T helper cells, cholangiocytes and hepatic stellate cells. In sum, our analysis reveals key clinically associated master regulators for BA.

Detection of Cytomegalovirus Infection in Infants with Biliary Atresia: A Meta-analysis

Objectives  Biliary atresia (BA) is the most common indication of liver transplantation in children. Several reports attributed BA to both prenatal and perinatal etiologies, including a viral infection-induced autoimmune response that targets the bile ducts. Cytomegalovirus (CMV) remains the most common virus being linked to BA. This meta-analysis aimed to estimate to what extent CMV infection is detected in patients with BA.

Methods  This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The databases of MEDLINE, Embase, Scopus, WHO-Virtual Health Library (VHL), ScienceDirect, and Google Scholar were used for the systematic search. The risk of bias was assessed using the Newcastle–Ottawa scale. Random effects model was used to estimate the pooled prevalence estimate with the corresponding 95% confidence interval (CI) using Comprehensive Meta-Analysis Software version 3.3.

Results  A total of 19 studies that fulfilled the eligibility criteria were included in the meta-analysis. The total number of infants with BA was 630 patients, and the pooled overall prevalence of CMV infection among them was 25.4% (95% CI: 15.9%–38.0%). There was high heterogeneity among studies (I ²  = 85.1%, p  < .001), and subgroup analyses showed significant regional differences (X ²  = 48.9, p <.001). Data on the prognosis of CMV-associated BA were scarce and obtainable from few studies that suggested an association between detection of CMV infection and poor prognosis of BA.

Conclusions  The limited available data demonstrates that the rate of detection of CMV infection is high in infants with BA. There is still a need for large studies with appropriate controls for obtaining more reliable results about the various aspects of the association between CMV infection and BA.

Biliary Atresia: Clinical Phenotypes and Aetiological Heterogeneity

Biliary atresia (BA) is an obliterative condition of the biliary tract that presents with persistent jaundice and pale stools typically in the first few weeks of life. While this phenotypic signature may be broadly similar by the time of presentation, it is likely that this is only the final common pathway with a number of possible preceding causative factors and disparate pathogenic mechanisms-i.e., aetiological heterogeneity. Certainly, there are distinguishable variants which suggest a higher degree of aetiological homogeneity such as the syndromic variants of biliary atresia splenic malformation or cat-eye syndrome, which implicate an early developmental mechanism. In others, the presence of synchronous viral infection also make this plausible as an aetiological agent though it is likely that disease onset is from the perinatal period. In the majority of cases, currently termed isolated BA, there are still too few clues as to aetiology or indeed pathogenesis.

Rodent models of cholestatic liver disease: A practical guide for translational research

Cholestatic liver disease denotes any situation associated with impaired bile flow concomitant with a noxious bile acid accumulation in the liver and/or systemic circulation. Cholestatic liver disease can be subdivided into different types according to its clinical phenotype, such as biliary atresia, drug-induced cholestasis, gallstone liver disease, intrahepatic cholestasis of pregnancy, primary biliary cholangitis and primary sclerosing cholangitis. Considerable effort has been devoted to elucidating underlying mechanisms of cholestatic liver injuries and explore novel therapeutic and diagnostic strategies using animal models. Animal models employed according to their appropriate applicability domain herein play a crucial role. This review provides an overview of currently available in vivo animal models, fit-for-purpose in modelling different types of cholestatic liver diseases. Moreover, a practical guide and workflow is provided which can be used for translational research purposes, including all advantages and disadvantages of currently available in vivo animal models.

High Rate of Cytomegalovirus Detection in Cholestatic Preterm Infants

Objectives: To evaluate the prevalence of cytomegalovirus (CMV) infection in preterm infants with cholestasis. Study design: Preterm infants (<37 weeks gestational age) with cholestasis were tested for CMV DNA using Taqman PCR in blood cells from sedimented whole blood, plasma, and urine. Infants were regarded as positive for CMV if any sample was tested positive. Their mothers were tested for CMV serostatus simultaneously. A control group of non-cholestatic preterm infants, and their mothers, were tested at a similar age. Results: A total of 69 preterm infants with a median gestational age of 26 weeks and 5 days were included, 45 cholestatic and 24 non-cholestatic. Of the cholestatic infants, 31/45 (69%) were CMV positive vs. 3/24 (13%) of the non-cholestatic infants (p < 0.001). Cholestatic infants were equally preterm as the non-cholestatic ones, but were more severely ill. After adjusting for the risk factors necrotizing enterocolitis, prolonged parenteral nutrition, and gestational age, being CMV positive remained significantly associated with cholestasis in a multivariable logistic regression model. Characteristics of CMV-positive and -negative cholestatic infants showed differences only for necrotizing enterocolitis, occurring in 55% (17/31) of CMV positive vs. 21% (3/14) of CMV negative (p = 0.054), and mortality. Eight cholestatic CMV-positive infants died (26%) vs. none of the CMV-negative infants (p = 0.044). Conclusions: CMV DNA was detected in two out of three cholestatic preterm infants, by far more often than in the non-cholestatic control group. Cholestasis with simultaneous detection of CMV DNA may be associated with increased mortality.

Prognosis of Biliary Atresia Associated With Cytomegalovirus: A Meta-Analysis

Objective: The etiology of biliary atresia is unclear, but viral infection has been implicated. The aim of the current meta-analysis was to investigate relationships between cytomegalovirus (CMV) and the prognosis of biliary atresia. Methods: PubMed, Embase, the Cochrane Library, the China National Knowledge Infrastructure database, and Wanfang Data electronic databases were searched for eligible studies. Each relevant text was thoroughly reviewed and examined, including related papers in their reference lists. Results: A total of nine studies including 784 patients were included in the analysis. Biliary atresia patients with CMV exhibited significantly lower jaundice clearance (odds ratio: 0.46, p < 0.0001; I ² = 15%, p = 0.31). There were no significant differences in the rates of cholangitis or native liver survival. CMV-pp65-positive biliary atresia patients had a significantly lower rate of jaundice clearance (odds ratio: 5.87, p = 0.003; I ² = 0%, p = 0.71) and a significantly higher rate of cholangitis (odds ratio: 0.21, p = 0.01; I ² = 0%, p = 0.43) than CMV antibody-positive biliary atresia patients. Conclusion: Biliary atresia patients who were also infected with CMV had a poorer prognosis, particularly with respect to jaundice clearance. CMV status may influence the prognosis of biliary atresia. Clinicians should be able to routinely identify the subset of biliary atresia patients who are also CMV-positive, in order to improve native liver survival.

Insight into the distinctive paradigm of Human Cytomegalovirus associated intrahepatic and extrahepatic cholestasis in neonates

Human Cytomegalovirus has been implicated as a probable cause for the development of hepatic cholestasis among neonates. Our study tried to ascertain the exact demographic, biochemical and immunological markers to differentially diagnose patients with HCMV associated intrahepatic and extrahepatic cholestasis and also decipher the phylogenetic variability among the viral strains infecting the two groups. A total of 110 neonates collected over a span of 2 years were selected for the study classified into four different groups based on the presence of hepatic cholestasis and active HCMV infection. Our analysis predicted that total Cholesterol, GGT, ALP and TNFα were the only significant biological markers with exact cut-off scores, capable of distinguishing between HCMV associated intrahepatic and extrahepatic cholestasis. We confirmed that in patients belonging to both of these groups, the inflammasome is activated and the extent of this activation is more or less same except for the initial activators NLRP3 and AIM2 respectively. When we performed two separate phylogenetic analyses with HCMV gM and gN gene sequences, we found that in both cases the sequences from the IHC and EHC groups formed almost separate phylogenetic clusters. Our study has shown that the HCMV clinical strains infecting at intrahepatic and extrahepatic sites are phylogenetically segregated as distinct clusters. These two separate groups show different physiological as well as immunological modulations while infecting a similar host.

Risk Prediction Scoring System to Predict the Postsurgical Outcomes of Biliary Atresia

Aim

To find out association between liver function, liver histopathology and outcomes of biliary atresia (BA) following Kasai Portoenterostomy (KPE).

Materials and Methods

This is a retrospective study of children who underwent KPE at a single institute by single surgeon. The patient records analyzed and data of complete blood counts, liver function tests, coagulation profile and histopathology reports collected. The outcomes recorded as alive and jaundice free, alive but jaundiced, and deceased. Statistical analysis done using SPSS 23.

Observations

Total of 148 children operated during January 2000 to December 2018. Of these, 26 matched inclusion criteria. The parameters assessed were percentage of direct bilirubin, ratios of Aspartate transaminase (AST) to Alanine transaminase (ALT); Gamma glutamyl transferase (GGT) to AST; GGT to ALT and Aspartate transaminase to platelet ratio index (APRi). Among histopathology reports, fibrosis grade and bile ductular size noted. Among 26, 16 alive and ten are deceased. Among 16 alive, all are jaundice free. Of the parameters, ratio of AST to ALT, APRi and grade of fibrosis found statistically significant and further analysis showed if AST to ALT ratio < 2.1, APRi < 1.8 and grade of fibrosis < four, irrespective of age at surgery, had 96.2 % probability of successful KPE. Based on these observations, a scoring system and risk prediction model constructed based on Receiver operating characteristic (ROC) curves which are first in BA management.

Results and Conclusion

Although numbers are sufficient for statistical analysis, we further intend to validate the scoring system in a prospective trial. BA children can be subjected to risk prediction model and KPE performed in those who have a score less than seven and offered to those with score between eight and 16 out of 20.

Key Message

The scoring system and risk prediction model can guide in the management and post-operative follow up of children with biliary atresia.

Rotavirus Infection and Cytopathogenesis in Human Biliary Organoids Potentially Recapitulate Biliary Atresia Development

There is substantial evidence indicating the possible involvement of rotavirus in biliary atresia (BA) development, at least in a subset of patients, but concrete proof remains lacking. In a mouse model, it has been well demonstrated that rotavirus can infect the biliary epithelium to cause biliary inflammation and obstruction, representing the pathogenesis of BA in humans. By using recently developed organoids technology, we now have demonstrated that human biliary organoids are susceptible to rotavirus infection, and this provokes active virus-host interactions and causes severe cytopathogenesis. Thus, our model recapitulates some essential aspects of BA development. Furthermore, we have demonstrated that antiviral drugs and neutralizing antibodies are capable of counteracting the infection and BA-like morphological changes, suggesting their potential for mitigating BA in patients.

Biliary atresia (BA) is a neonatal liver disease characterized by progressive fibroinflammatory obliteration of both intrahepatic and extrahepatic bile ducts. The etiologies of BA remain largely unknown, but rotavirus infection has been implicated at least for a subset of patients, and this causal relation has been well demonstrated in mouse models. In this study, we aim to further consolidate this evidence in human biliary organoids. We obtained seven batches of human biliary organoids cultured from fetal liver, adult liver, and bile duct tissues. We found that these organoids are highly susceptible and support the full life cycle of rotavirus infection in three-dimensional culture. The robust infection triggers active virus-host interactions, including interferon-based host defense mechanisms and injury responses. We have observed direct cytopathogenesis in organoids upon rotavirus infection, which may partially recapitulate the development of BA. Importantly, we have demonstrated the efficacy of mycophenolic acid and interferon alpha but not ribavirin in inhibiting rotavirus in biliary organoids. Furthermore, neutralizing antibody targeting rotavirus VP7 protein effectively inhibits infection in organoids. Thus, we have substantiated the causal evidence of rotavirus inducing BA in humans and provided potential strategies to combat the disease.

Evaluation of Perioperative Complications in the Management of Biliary Atresia

Purpose: To analyze the influence of perioperative complications in the management of biliary atresia (BA). Methods: A retrospective study was performed using a total of 422 BA patients who underwent Kasai portoenterostomy (KPE) in a single institution between February 2016 and May 2017. Data on patients' clinical characteristics, laboratory examinations, perioperative complications, and outcomes were collected. Unpaired two-tailed t-test and χ² test were employed for the comparison between BA patients with and without perioperative complications. Cox regression analysis was used to screen the risk factors for 2-years NLS in BA, and their influence on the 2-years NLS was analyzed using Kaplan-Meier survival analysis as well as the log-rank test. Results: The incidence of perioperative complications, 6-months jaundice clearance (JC) and 2-years native liver survival (NLS) rate were 60.4, 59.5, and 56.6%, respectively. Patients with perioperative complications had lower serum albumin (ALB) level, but higher aspartate aminotransferase-to-platelet ratio index (APRI) and international normalized ratio (INR) levels when compared with those without perioperative complications (ALB, P < 0.05; APRI, P < 0.01; INR, P < 0.05). Moreover, perioperative complications were correlated with glucocorticoid administration (P = 0.002). Univariate Cox regression analysis showed no relationship between perioperative complications and 2-years NLS (P > 0.05). However, multivariate Cox regression analysis indicated 6-months JC was an independent protective factor for 2-years NLS [P < 0.0001, hazard ratio (HR) = 0.074, 95% confidence interval = 0.05-0.11], and concordance index of this prediction model including age, weight, APRI, glucocorticoid, and 6-months JC was 0.811. Conclusion: Although perioperative complication is common during and after KPE, it had no influence on the prognosis of BA. However, assessment of the serum level of total bilirubin after KPE may serve as an important predictor for the outcome in BA.

Adjuvant therapy of cytomegalovirus IgM + ve associated biliary atresia: Prima facie evidence of effect

AIM OF STUDY

CMV-IgM + ve associated biliary atresia (CMV-BA) is a distinct etiological subgroup characterized by older age at presentation and a greater degree of inflammation and hepatic fibrosis, leading to a worse outcome. We report our experience with adjuvant antiviral therapy after Kasai portoenterostomy (KPE).

METHODS

Single-center prospective database identification of CMV-IgM + ve associated BA managed between 2003 and 2017. Since 2011, IV ganciclovir (5 mg/kg b.d.) and/or oral valganciclovir (520 mg/m² b.d.) were started in the early postoperative period in selected cases and continued until negativity of CMV DNA load [Anti-Viral Therapy (AVT) Group 1]. Clearance of jaundice was defined as achieving a total bilirubin ≤20 μmol/L in post-KPE period and tested with a Fisher test; native liver survival (NLS) and overall actuarial survival (OS) were compared with untreated BA CMV IgM + ve patients (Group 2) using a Log-Rank test. A P value of <0.05 was regarded as significant. Data are quoted as median (IQ range).

RESULTS

During the 14-year period, 376 infants with histologically confirmed BA were treated; of those 38(10%) were CMV IgM + ve at presentation. One child was considered too late at presentation for KPE and underwent primary liver transplantation while another only started AVT one month after KPE. Both were excluded from survival analysis. Therefore 36 underwent KPE [AVT Group 1 (n = 8) and Control Group 2 (n = 28)]. Overall age at surgery was 67(53-77) days. There was no difference in age at surgery (P = 0.26); bilirubin (P = 0.12); or AST (P = 0.15) between Group 1 and Group 2. Viral load data were available in 16 with a trend towards higher counts in the AVT group 1 [4935 (2668-18,817) vs. 1296 (253-10,471) c/ml; P = 0.06]. Clearance of jaundice was higher in AVT Group 1 (75% vs 21%, P = 0.009). There was no difference in OS (P = 0.24) but NLS was improved in the AVT Group 1 (75% vs. 25% at 2 years; P = 0.04).

CONCLUSIONS

Although this finding may be regarded as preliminary, adjuvant antiviral therapy appeared to improve outcome in infants with CMV IgM + ve BA.

LEVEL OF EVIDENCE

III.

Hepatoportoenterostomy surgery technique

Biliary atresia (BA) is a pathology that causes jaundice in children because of an obstruction of the obliterated biliary tract. Despite being considered a rare disease, the incidence can reach 1/2400 live births in the Pacific region. The etiology is unknown. If untreated, it will lead to cirrhosis and death. Early operation (within 60 days after birth) is the most important prognostic factor. The objective of this article is to present the technical description step by step of a hepatoportoenterostomy operation in a female 61 days of age with BA.

A Rotavirus-Induced Mouse Model to Study Biliary Atresia and Neonatal Cholestasis

Biliary atresia is a devastating neonatal cholangiopathy that affects both extra- and intrahepatic bile ducts progressing to fibrosis and end-stage liver disease by 2 years of age. Despite re-establishment of biliary drainage following a Kasai portoenterostomy (surgical procedure), many infants develop fibrosis requiring liver transplant. In the murine model of biliary atresia, rhesus rotavirus infection of newborn pups results in a cholangiopathy paralleling human biliary atresia and is used to study mechanistic aspects of the disease. The infected mice displayed histopathological signs similar to human biliary atresia, with bile duct obstruction, bile duct proliferation, and liver inflammation with fibrosis.

Genetic investigation into an increased susceptibility to biliary atresia in an extended New Zealand Māori family

Background

Biliary atresia (BA), a fibrosing disorder of the developing biliary tract leading to liver failure in infancy, has an elevated incidence in indigenous New Zealand (NZ) Māori. We investigated a high rate of BA in a group of children (n = 12) belonging to a single Māori iwi (or ‘tribe’, related through a remote ancestor).

Methods

Population and geographical data was used to estimate the rate of BA in Māori sub-groups, and a pedigree linking most of the affected children was constructed from oral and documented history. Array genotyping was used to examine hypotheses about the inheritance of a possible genetic risk factor, and the history of the affected population, and Exome Sequencing to search for candidate genes.

Results

Most of these affected children (n = 7) link to a self-reported pedigree and carry a 50-fold increase in BA risk over unrelated Māori (χ² = 296P < 0.001, 95% CI 23–111). Genetic analysis using FEstim and SNP array genotypes revealed no evidence for elevated consanguinity between parents of affected children (FEstim: F (2,21) = 0.469, P > 0.63). Genome-wide quantitation of intervals of contiguous, homozygous-by-state markers reached a similar conclusion (F (2,399) = 1.99, P = 0.138). Principal component analysis and investigation with STRUCTURE found no evidence of increased allele frequency of either a recessive variant, or additive, low-risk variants due to reproductive isolation. To identify candidate causal factors, Exome Sequencing datasets were scrutinised for shared rare coding variants across 8 affected individuals. No rare, non-synonymous, phylogenetically conserved variants were common to 6 or more affected children.

Conclusion

The substantially elevated risk for development of BA in this subgroup could be mediated by genetic factors, but the iwi exhibits no properties indicative of recent or remote reproductive isolation. Resolution of any risk loci may rely on extensive genomic sequencing studies in this iwi or investigation of other mechnaisms such as copy number variation.

Electronic supplementary material

The online version of this article (10.1186/s12920-018-0440-0) contains supplementary material, which is available to authorized users.

Detection of Cytomegalovirus in Liver Tissue by Polymerase Chain Reaction in Infants With Neonatal Cholestasis

AIM

Cytomegalovirus (CMV) is associated with neonatal cholestasis (NC). Diagnosis of CMV infection is most often based on either positive blood CMV IgM or CMV blood polymerase chain reaction (PCR). Isolation of CMV in liver tissues in patients with NC has rarely been reported. This study was undertaken to see if CMV is present in liver tissues of patients with NC and evaluate the correlation between positive CMV PCR in liver tissue with the serology and blood PCR.

METHODS

This study was conducted in 31 infants with NC from June 2015 to December 2016. All patients underwent blood CMV IgM, blood CMV PCR and liver CMV PCR. Prevalence of CMV in NC based on positive liver CMV PCR was calculated. Sensitivity and specificity of the serologic markers and blood CMV PCR to identify CMV infection in the liver was determined.

RESULTS

CMV IgM was positive in 13 (42%) patients, CMV IgG was positive in 26 (84%) patients and blood CMV PCR was positive in 23 (74%) patients. Liver CMV PCR was positive in 16 (52%) patients. Fifteen (48%) patients had biliary atresia (BA), 10 (32%) patients had neonatal hepatitis, 5 (16%) had paucity of bile ducts and 1 (3%) had ascending cholangitis. Of the 16 patients with positive liver CMV PCR, 8 (50%) had BA, 4 (25%) had neonatal hepatitis, 3 (19%) had paucity of bile ducts and 1 (6%) had ascending cholangitis. Sensitivity of blood CMV IgM in relation to liver CMV PCR was 69% and specificity was 61%. Sensitivity of blood CMV PCR was 61% and specificity was 71% when compared with liver CMV PCR.

CONCLUSION

CMV is present in the liver tissues of more than half the patients with NC. Serology or blood CMV PCR is apparently not an accurate marker of CMV in the liver tissue. Also, CMV infection in children seems to be associated equally with BA or non-BA neonatal hepatitis.

Role of viruses in biliary atresia: news from mice and men

Biliary atresia (BA) is still an enigmatic disease of unknown etiology and cryptic pathomechanism. Despite the fact that BA is rated among rare diseases, it represents the most frequent indication for pediatric liver transplantation. Although every effort is made to elucidate the origin of the ongoing deterioration of liver function, no breakthrough has so far been achieved, which switches the surgical but symptomatic therapy to a cause-oriented approach. The nowadays leading hypothesis focuses on hepatotropic virus as a triggering agent for an autoimmunological self-limiting inflammatory process along the entire biliary tree. The present review highlights the current state of research on the factor "viruses in biliary atresia" in both patients undergoing the Kasai procedure and the virus-induced BA mouse model.

Update on investigations pertaining to the pathogenesis of biliary atresia

Biliary atresia is a devastating biliary disease of neonates that results in liver transplantation for the vast majority. The etiology of biliary atresia is unknown and is likely multifactorial, with components of genetic predisposition, environmental trigger and autoimmunity contributing to disease pathogenesis. This review highlights recent work related to investigations of disease pathogenesis in biliary atresia.

Disturbance in Plasma Metabolic Profile in Different Types of Human Cytomegalovirus-Induced Liver Injury in Infants

Human cytomegalovirus (HCMV) infection in infants is a global problem and the liver is a target organ of HCMV invasion. However, the mechanism by which HCMV causes different types of liver injury is unclear, and there are many difficulties in the differential diagnosis of HCMV infantile cholestatic hepatopathy (ICH) and extrahepatic biliary atresia (EHBA). We established a non-targeted gas chromatography-mass spectrometry metabolomics method in conjunction with orthogonal partial least squares-discriminate analysis based on 127 plasma samples from healthy controls, and patients with HCMV infantile hepatitis, HCMV ICH, and HCMV EHBA to explore the metabolite profile of different types of HCMV-induced liver injury. Twenty-nine metabolites related to multiple amino acid metabolism disorder, nitrogen metabolism and energy metabolism were identified. Carbamic acid, glutamate, L-aspartic acid, L-homoserine, and noradrenaline for HCMV ICH vs. HCMV EHBA were screened as potential biomarkers and showed excellent discriminant performance. These results not only revealed the potential pathogenesis of HCMV-induced liver injury, but also provided a feasible diagnostic tool for distinguishing EHBA from ICH.

Guideline for the Evaluation of Cholestatic Jaundice in Infants: Joint Recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition

Cholestatic jaundice in infancy affects approximately 1 in every 2500 term infants and is infrequently recognized by primary providers in the setting of physiologic jaundice. Cholestatic jaundice is always pathologic and indicates hepatobiliary dysfunction. Early detection by the primary care physician and timely referrals to the pediatric gastroenterologist/hepatologist are important contributors to optimal treatment and prognosis. The most common causes of cholestatic jaundice in the first months of life are biliary atresia (25%-40%) followed by an expanding list of monogenic disorders (25%), along with many unknown or multifactorial (eg, parenteral nutrition-related) causes, each of which may have time-sensitive and distinct treatment plans. Thus, these guidelines can have an essential role for the evaluation of neonatal cholestasis to optimize care. The recommendations from this clinical practice guideline are based upon review and analysis of published literature and the combined experience of the authors. The committee recommends that any infant noted to be jaundiced after 2 weeks of age be evaluated for cholestasis with measurement of total and direct serum bilirubin, and that an elevated serum direct bilirubin level (direct bilirubin levels >1.0 mg/dL or >17 μmol/L) warrants timely consideration for evaluation and referral to a pediatric gastroenterologist or hepatologist. Of note, current differential diagnostic plans now incorporate consideration of modern broad-based next-generation DNA sequencing technologies in the proper clinical context. These recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the care of all infants with cholestasis. Broad implementation of these recommendations is expected to reduce the time to the diagnosis of pediatric liver diseases, including biliary atresia, leading to improved outcomes.

CD13 Autoantibodies Are Elevated in Sera From Mothers of Infants With Neonatal Cholestasis of Different Causes

OBJECTIVES

Human cytomegalovirus (HCMV) infection induces production of CD13-specific autoantibodies, which may promote inflammation and tissue damage. HCMV infection has been suggested as a cause of biliary atresia (BA), but little is known of its role in other forms of neonatal cholestasis. We studied serum levels of CD13-specific autoantibodies in mothers of infants with neonatal cholestasis of different causes, including BA, and in mothers of healthy, term infants without cholestasis, as well as in healthy blood donors.

METHODS

Using fluorescence-activated cell sorting, we measured CD13-specific autoantibody levels in serum from the above-mentioned groups. In addition, the effect of serum from mothers of infants with neonatal cholestasis was tested on the differentiation of monocytes into macrophages.

RESULTS

CD13-specific autoantibodies were found in mothers of infants with neonatal cholestasis, but not in mothers of infants without cholestasis and healthy blood donors, and were associated with HCMV seropositivity. Sera from mothers of infants with all forms of neonatal cholestasis inhibited differentiation of monocytes into macrophages, but this was not dependent on CD13-specific autoantibodies.

CONCLUSIONS

The significantly higher frequency of CD13-specific autoantibodies in mothers of infants with neonatal cholestasis of all forms compared with mothers of healthy infants without cholestasis suggests an association, but does not prove that they are pathogenic. The presence of CD13-specific autoantibodies does not correlate with HCMV IgG serostatus, suggesting a more complicated mechanism that possibly reflects active HCMV infection in these individuals. Further studies are needed to elucidate whether these autoantibodies contribute to the development of cholestasis or represent an epiphenomenon.

Cytomegalovirus hepatitis in 49 pediatric patients with normal immunity

BACKGROUND/AIM

Cytomegalovirus (CMV) hepatitis is generally asymptomatic or rarely can lead to severe complications in immunocompetent hosts. This study aims to evaluate CMV hepatitis in immunocompetent young children, which is discussed relatively rarely in the literature.

MATERIALS AND METHODS

A retrospective review of 49 pediatric patients with CMV hepatitis from January 2005 to December 2010 was performed.

RESULTS

The median age of the patients was 5.81 ± 6.49 months and 57.1% were female. Complaints were prolonged jaundice, vomiting, diarrhea, and abdominal distension. Seventeen patients (34.6%) had congenital or probable congenital CMV infection, while 32/49 (65.3%) had perinatal CMV infection. CMV hepatitis was accompanied by other system findings in 22 patients (44.9%), and only liver involvement was present in 27/49 (55.1%). Alanine aminotransferase and aspartate aminotransferase were elevated together in all patients. Cholestatic hepatitis was present in 13 patients (26.5%). Four patients (8.16%) were treated with ganciclovir. Complete improvement of hepatitis occurred in 48/49 (97.95%). The recovery time of liver function tests was 7-180 days (mean: 53.92 ± 40.8).

CONCLUSION

CMV hepatitis is usually mild and has a good outcome in immunocompetent individuals. However, cases should be carefully evaluated due to the important role of CMV in the etiology of infantile and neonatal hepatitis.

Cytomegalovirus-associated biliary atresia: An aetiological and prognostic subgroup

BACKGROUND AND AIMS

Perinatal cytomegalovirus (CMV) infection is a possible cause or trigger of biliary atresia though clinical evidence is scant. We hypothesised that CMV IgM+ve biliary atresia is a separate clinical entity compared to CMV IgM-ve biliary atresia.

METHODS

Prospective single-centre study. 210 infants with histologically confirmed biliary atresia were treated in our institution (Jan. 2004 to Dec. 2011); of these 20 (9.5%) were CMV IgM+ve at presentation. We compared these with 111 infants who were CMV IgM-ve (controls) for clinical features, biochemistry at presentation and outcome following Kasai portoenterostomy (KPE). A blinded comparison of age-matched liver histology was also performed. Data are quoted as median (interquartile range). A P value ≤ 0.05 was regarded as significant.

RESULTS

Infants with CMV IgM+ve biliary atresia were older at Kasai portoenterostomy (or laparotomy) [70 (60-80) days vs. 56 (44-75)days; P = 0.003] and were more jaundiced [175 (147-224) vs. 140 (121-181) μmol/L; P = 0.002+ with higher AST*287 (157-403) vs. 180 (133-254) IU/L; P = 0.005] and aspartate aminotransferase-to-platelet ratio index [1.1 (0.79-3.0) vs. 0.63 (0.43-0.95)] levels. Liver histology: CMV IgM+ve biliary atresia was characterised by a greater degree of inflammation (P < 0.0001) and fibrosis (P = 0.02), whereas CMV IgM-ve isolated biliary atresia had a higher degree of lobular cholestasis (P = 0.001). This effect was independent of the effects of age at KPE.

OUTCOME

CMV IgM+ve biliary atresia had a poorer outcome with a reduced clearance of jaundice (15% vs. 52.2%; P = 0.002), native liver survival (P < 0.0001) and increased mortality (P = 0.002).

CONCLUSIONS

CMV IgM+ve biliary atresia is a distinct clinical and pathological entity with a diminished response to Kasai portoenterostomy.

Th-17 cells infiltrate the liver in human biliary atresia and are related to surgical outcome

BACKGROUND

Biliary atresia (BA), a cholangiopathy of unknown etiology is associated with intrahepatic mononuclear cell infiltrate. An abnormal reaction to viral exposure has been hypothesized in some cases. We aimed to investigate the nature of the CD4+ hepatic infiltrate in defined clinical variants of BA by quantification of inflammatory cell components.

METHODS

Liver biopsies of infants obtained at Kasai portoenterostomy (KPE) were stained immunohistochemically using monoclonal antibodies to Tbet, GATA-3, FOXP3 and interleukin (IL) 17, identifying Th-1, Th-2, Tregs and Th-17 cells respectively. T cells were counted with the aid of a graticule. Data are reported as median (range) of cells per high-power-field (×400) and compared using nonparametric statistical tests with P≤0.05 regarded as significant.

RESULTS

Liver biopsies from BA (n=37) and age-matched cholestatic controls (e.g. alpha-1-anti trypsin deficiency, Alagilles syndrome, n=12) were investigated. BA infants were divided into three groups: cytomegalovirus IgM +ve (CMV; n=9); BA splenic malformation (BASM; n=9) and isolated BA (IBA; n=19). All T-cell subsets were present in the portal tracts, with an overrepresentation of Th-1 (P<0.001) and Th-17 (P<0.03), but not Th-2 (P=0.94) or Tregs (P=0.15), compared to controls. Th-1 cells predominated in the CMV group; (18 [7-37] vs. 3 [0-14] [BASM] and vs. 5 [3-23] [IBA]; P<0.01 both), while no subgroup differences were seen for Th-17 cells. The degree of Th-1 cell infiltrate inversely correlated with platelet count (rS=-0.49; P<0.01). Th-17 cells were fewer (6 [2-11] vs. 11 [8-20]; P=0.02) in infants who cleared their jaundice (n=15, <20μmol/L) although this did not translate to improved native liver survival (P=0.17).

CONCLUSIONS

Th-17 cells infiltrate the liver in BA and are associated with a worse surgical outcome; a Th-1 profile predominates in CMV-associated BA.

Biliary Atresia: Clinical Lessons Learned

Biliary atresia is a rare disease of unclear etiology, in which obstruction of the biliary tree causes severe cholestasis leading to cirrhosis and ultimately death if left untreated. Biliary atresia is the leading cause of neonatal cholestasis and the most frequent indication for pediatric liver transplantation. Any infant with persistent jaundice beyond 2 weeks of life needs to be evaluated for biliary atresia with fractionation of the bilirubin into conjugated and unconjugated portions. Early performance of a hepatoportoenterostomy in the first 45 days of life to restore bile flow and lessen further damage to the liver is thought to optimize outcome. Despite surgery, progressive liver scarring occurs, and 80% of patients with biliary atresia will require liver transplantation during childhood.

Evidence for viral infection as a causative factor of human biliary atresia

OBJECTIVES

To explore the evidence for viral infections triggering human biliary atresia (BA) by reviewing archival original articles that analyzed human samples via polymerase chain reaction (PCR) experiments, considering the recent experimental trend of extensive use of rotaviral BA animal models.

METHODS

A PubMed search retrieved original articles that reported the results of PCR experiments for detecting viral DNA or RNA in patient samples as proof of past infection. Search terms included the often-debated DNA or RNA viruses and BA. Special focus was directed toward PCR analyses that targeted reovirus and rotavirus, where PCR accuracy, specimen characteristics and their interpretations were compared.

RESULTS

Nineteen studies were conducted on 16 different kinds of viruses using PCR, with 5 studies on reovirus, 3 on rotavirus, 10 on cytomegalovirus, 5 on Epstein-Barr virus, 4 on parvovirus B19, and so on. Among the papers suggesting a possible viral link to only BA, there was no study on reovirus, 1 on rotavirus, 3 on cytomegalovirus, 1 on EB virus, and 1 on papillomavirus. Of the 6 PCR studies on Reoviridae, 3 on reovirus and 2 on rotavirus were evaluated rigorously for experimental accuracy, including their sensitivity. Two research groups analyzed preoperative stool samples in addition to generic hepatobiliary tissue obtained at surgery. Sample collection timing varied widely, with storage period prior to PCR experimentation not revealed in most reports on Reoviridae.

CONCLUSION

Although a considerable number of PCR studies have sought to clarify a viral role in the pathogenesis of BA using human samples, the findings have been contradictory and have not succeeded in achieving an obvious differentiation between causative and accidental infection of the focused virus. Reproducible and convincing evidence for a causative Reoviridae infection has been lacking based on objective data from highly sensitive PCR experiments. Even though the possibility remains of viral disappearance at the timing of collection, to avoid further ambiguous interpretations of PCR results, rigorous and meticulous collection of large numbers of specimens at carefully planned timing, along with a strictly adjusted and finely tuned PCR system, is strongly recommended for obtaining more reliable and consistent results.

The Sea Lamprey as an Etiological Model for Biliary Atresia

Biliary atresia (BA) is a progressive, inflammatory, and fibrosclerosing cholangiopathy in infants that results in obstruction of both extrahepatic and intrahepatic bile ducts. It is the most common cause for pediatric liver transplantation. In contrast, the sea lamprey undergoes developmental BA with transient cholestasis and fibrosis during metamorphosis, but emerges as a fecund adult with steatohepatitis and fibrosis in the liver. In this paper, we present new histological evidence and compare the sea lamprey to existing animal models to highlight the advantages and possible limitations of using the sea lamprey to study the etiology and compensatory mechanisms of BA and other liver diseases. Understanding the signaling factors and genetic networks underlying lamprey BA can provide insights into BA etiology and possible targets to prevent biliary degeneration and to clear fibrosis. In addition, information from lamprey BA can be used to develop adjunct treatments for patients awaiting or receiving surgical treatments. Furthermore, the cholestatic adult lamprey has unique adaptive mechanisms that can be used to explore potential treatments for cholestasis and nonalcoholic steatohepatitis (NASH).

Laparoscopic portoenterostomy versus open portoenterostomy for the treatment of biliary atresia: a systematic review and meta-analysis of comparative studies

BACKGROUND

Open portoenterostomy (OPE) remains the mainstay in treatment of biliary atresia, while during the past several years, the laparoscopic portoenterostomy (LPE) has been widely introduced. However, safety of LPE remains a major concern. Thus, we conducted a systematic review and meta-analysis to review the currently available data comparing LPE and OPE.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Ovid, Elsevier, Google Scholar Embase, Cohrane library.

STUDY SELECTION

Comparative cohort studies.

DATA EXTRACTION

Two investigators independently assessed selected studies and extracted the following information: study characteristics, quality, outcomes data, etc.

RESULTS

Eleven studies about the effectiveness of LPE compared with OPE were performed by meta-analysis. Meta-analysis found no significant difference between the two groups in operative time, hospital stay, intraoperative blood loss, early clearance of jaundice, cholangitis and variceal bleeding. In addition, the rate of 2-year survival with native liver was significantly high in OPE group than in LPE group.

CONCLUSION

Laparoscopic portoenterostomy could not replace open portoenterostomy and open Kasai portoenterostomy remains the gold standard in the treatment of biliary atresia.

Low doses of CMV induce autoimmune-mediated and inflammatory responses in bile duct epithelia of regulatory T cell-depleted neonatal mice

Recent studies have indicated that perinatal infection with cytomegalovirus (CMV) may promote bile duct damage in biliary atresia (BA) and that the decreased regulatory T cell (Treg) percentage associated with BA may further amplify the bile duct damage. Although a majority of BA patients have had previous CMV infections and lower percentages of Tregs, it is unknown whether an initial exposure to a low dose of CMV could induce exaggerated and progressive biliary injury. A Treg-depleted neonatal mouse was infected with low-dose CMV (LD-CMV) as a model to study BA patients. LD-CMV infection in Treg-depleted mice induced extensive inflammation in both the intrahepatic and extrahepatic bile ducts, accompanied with injury to and atresia of intrahepatic bile ducts and partial obstruction of the extrahepatic bile ducts. Serum total and direct bilirubin amounts were also elevated. Evidence for the involvement of cellular and humoral autoimmune responses in LD-CMV-infection of Treg-depleted mice was also obtained through detection of increased percentages of CD3 and CD8 mononuclear cells and serum autoantibodies reactive to bile duct epithelial proteins, one of which was identified as α-enolase. Depletion of Tregs that can lead to the decreased inhibition of aberrantly activated hepatic T-lymphocytes and generation of autoantibodies may lead to further injury. Increased hepatic expression of Th1-related genes (TNF-α), IFN-γ-activated genes (STAT-1) and Th1 cytokines (TNF-α, lymphotactin, IL-12p40 and MIP -1γ) were also identified. In conclusion, autoimmune-mediated and inflammatory responses induced by LD-CMV infection in Treg-depleted mice results in increased intrahepatic and extrahepatic bile duct injury and contributed to disease progression.

Association between single nucleotide polymorphisms in the ADD3 gene and susceptibility to biliary atresia

Background and Objectives

Based on the results of previous studies, the ADD3 gene, located in the 10q24.2 region, may be a susceptibility gene of biliary atresia (BA). In this study, two single nucleotide polymorphisms (SNPs) in the ADD3 gene, rs17095355 C/T and rs10509906 G/C, were selected to investigate whether there is an association between these SNPs and susceptibility to BA in a Chinese population.

Methods

A total of 752 Han Chinese (134 BA cases and 618 ethnically matched healthy controls) were included in the present study. The ADD3 gene polymorphisms were genotyped using a TaqMan genotyping assay.

Results

Positive associations were found for the SNP rs17095355 in the codominant model; specifically, the frequencies of the CT and TT genotypes and the T allele were higher in the cases than the controls, demonstrating a significant risk for BA (odds ratio [OR] = 1.62, 95% confidence interval [CI] = 1.02–2.58; OR = 2.89, 95% CI = 1.72–4.86; and OR = 1.75, 95% CI = 1.34–2.29, respectively). Regarding rs10509906, the per-C-allele conferred an OR of 0.70 (95% CI = 0.49–1.00) under the additive model. A greater risk of BA was associated with the T_a-G_b (a for rs17095355 and b for rs10509906) haplotype (OR = 1.82, 95% CI = 1.27–2.61) compared with the C_a-C_b haplotype.

Conclusion

This study suggests that the ADD3 gene plays an important role in BA pathogenesis and reveals a significant association between two SNPs, rs17095355 and rs10509906, and BA.

Aetiology of biliary atresia: what is actually known?

Biliary atresia (BA) is a rare disease of unknown etiology and unpredictable outcome, even when there has been timely diagnosis and exemplary surgery. It has been the commonest indication for liver transplantation during childhood for the past 20 years. Hence much clinical and basic research has been directed at elucidating the origin and pathology of BA. This review summarizes the current clinical variations of BA in humans, its occasional appearance in animals and its various manifestations in the laboratory as an experimental model.

Role of myeloid differentiation factor 88 in Rhesus rotavirus-induced biliary atresia

BACKGROUND

Biliary atresia (BA) is a unique neonatal disease resulting from inflammatory and fibrosing obstruction of the extrahepatic biliary tree. Previous studies have demonstrated the critical role of innate immunity and the Th1 response to activated inflammatory cells and overexpressed cytokines in the pathogenesis of BA. Myeloid differentiation factor 88 (MyD88) is a critical adaptor molecule that has been shown to play a crucial role in immunity. We investigated the role of MyD88 in the inflammatory response and development of cholangiopathy in murine BA.

METHODS

MyD88 knockout (MyD88(-/-)) and wild-type (WT) BALB/c pups were injected with Rhesus rotavirus or saline on day 1 of life. The mice were monitored for clinical symptoms of BA, including jaundice, acholic stools, bilirubinuria, and death. The liver and extrahepatic bile ducts were harvested for histologic evaluation and the quantification of viral content, determination of cytokine expression, and detection of inflammatory cells.

RESULTS

Rhesus rotavirus infection produced symptoms in 100% of both MyD88(-/-) and WT pups, with survival of 18% of WT and 0% of MyD88(-/-) mice. Histologic analysis demonstrated bile duct obstruction in both MyD88(-/-) and WT mice. Viral titers obtained 7 d after infection and expression of interferon-γ and tumor necrosis factor-α at day 3, 5, 8, and 12 after infection revealed no significant differences between the WT and MyD88(-/-) mice. Flow cytometry demonstrated similar levels of activated CD8+ T cells and natural killer cells.

CONCLUSIONS

The pathogenesis of murine BA is independent of the MyD88 signaling inflammatory pathway, suggesting alternative mechanisms are crucial in the induction of the model.

Biliary atresia: 50 years after the first kasai

Biliary atresia is a rare neonatal disease of unknown etiology, where obstruction of the biliary tree causes severe cholestasis, leading to biliary cirrhosis and death in the first years of life, if the condition is left untreated. Biliary atresia is the most frequent surgical cause of cholestatic jaundice in neonates and should be evoked whenever this clinical sign is associated with pale stools and hepatomegaly. The treatment of biliary atresia is surgical and currently recommended as a sequence of, eventually, two interventions. During the first months of life a hepatoportoenterostomy (a "Kasai," modifications of which are discussed in this paper) should be performed, in order to restore the biliary flow to the intestine and lessen further damage to the liver. If this fails and/or the disease progresses towards biliary cirrhosis and life-threatening complications, then liver transplantation is indicated, for which biliary atresia represents the most frequent pediatric indication. Of importance, the earlier the Kasai is performed, the later a liver transplantation is usually needed. This warrants a great degree of awareness of biliary atresia, and the implementation of systematic screening for this life-threatening pathology.