Outcome of Alagille Syndrome Patients Who Had Previously Received Kasai Operation during Infancy: A Single Center Study

Exome-wide assessment of isolated biliary atresia: A report from the National Birth Defects Prevention Study using child-parent trios and a case-control design to identify novel rare variants

The etiology of biliary atresia (BA) is unknown, but recent studies suggest a role for rare protein-altering variants (PAVs). Exome sequencing data from the National Birth Defects Prevention Study on 54 child-parent trios, one child-mother duo, and 1513 parents of children with other birth defects were analyzed. Most (91%) cases were isolated BA. We performed (1) a trio-based analysis to identify rare de novo, homozygous, and compound heterozygous PAVs and (2) a case-control analysis using a sequence kernel-based association test to identify genes enriched with rare PAVs. While we replicated previous findings on PKD1L1, our results do not suggest that recurrent de novo PAVs play important roles in BA susceptibility. In fact, our finding in NOTCH2, a disease gene associated with Alagille syndrome, highlights the difficulty in BA diagnosis. Notably, IFRD2 has been implicated in other gastrointestinal conditions and warrants additional study. Overall, our findings strengthen the hypothesis that the etiology of BA is complex.

Protocols of Investigation of Neonatal Cholestasis-A Critical Appraisal

Neonatal cholestasis (NC) starts during the first three months of life and comprises extrahepatic and intrahepatic groups of diseases, some of which have high morbimortality rates if not timely identified and treated. Prolonged jaundice, clay-colored or acholic stools, and choluria in an infant indicate the urgent need to investigate the presence of NC, and thenceforth the differential diagnosis of extra- and intrahepatic causes of NC. The differential diagnosis of NC is a laborious process demanding the accurate exclusion of a wide range of diseases, through the skillful use and interpretation of several diagnostic tests. A wise integration of clinical-laboratory, histopathological, molecular, and genetic evaluations is imperative, employing extensive knowledge about each evaluated disease as well as the pitfalls of each diagnostic test. Here, we review the difficulties involved in correctly diagnosing the cause of cholestasis in an affected infant.

Multidisciplinary Management of Alagille Syndrome

Alagille syndrome (ALGS) is an autosomal dominant disorder characterized by involvement of various organ systems. It predominantly affects the liver, skeleton, heart, kidneys, eyes and major blood vessels. With myriads of presentations across different age groups, ALGS is usually suspected in infants presenting with high gamma glutamyl transpeptidase cholestasis and/or congenital heart disease. In children it may present with decompensated cirrhosis, intellectual disability or short stature, and in adults vascular events like stroke or ruptured berry aneurysm are more commonly noted. Liver transplantation (LT) is indicated in children with cholestasis progressing to cirrhosis with decompensation. Other indications for LT include intractable pruritus, recurrent fractures, hepatocellular carcinoma and disfiguring xanthomas. Due to an increased risk of renal impairment noted in ALGS, these patients would require optimized renal sparing immunosuppression in the post-transplant period. As the systemic manifestations of ALGS are protean and a wider spectrum is being increasingly elucidated, a multidisciplinary team needs to be involved in managing these patients. Moreover, many basic-science and clinical questions especially with regard to its presentation and management remain unanswered. The aim of this review is to provide updated insights into the management of the multi-system involvement of ALGS.

Diagnostic approach to neonatal and infantile cholestasis: A position paper by the SIGENP liver disease working group

Neonatal and infantile cholestasis (NIC) can represent the onset of a surgically correctable disease and of a genetic or metabolic disorder worthy of medical treatment. Timely recognition of NIC and identification of the underlying etiology are paramount to improve outcomes. Upon invitation by the Italian National Institute of Health (ISS), an expert working grouped was formed to formulate evidence-based positions on current knowledge about the diagnosis of NIC. A systematic literature search was conducted to collect evidence about epidemiology, etiology, clinical aspects and accuracy of available diagnostic tests in NIC. Evidence was scored using the GRADE system. All recommendations were approved by a panel of experts upon agreement of at least 75% of the members. The final document was approved by all the panel components. This position document summarizes the collected statements and defines the best-evidence diagnostic approach to cholestasis in the first year of life.

Re-evaluation of Laparoscopic Hepatic Subcapsular Spider-Like Telangiectasis Sign: A Highly Accurate Method to Diagnose Biliary Atresia in Infants

OBJECTIVE

Operative cholangiography, the gold standard for the diagnosis of biliary atresia (BA), is being challenged due to an increase in the studies of misdiagnosis. A previous study has shown that the laparoscopic hepatic subcapsular spider-like telangiectasis (HSST) sign was accurate for diagnosing BA. This study aims to compare the performance of the HSST sign with cholangiography in the identification of BA.

METHODS

We prospectively screened consecutive infants with cholestasis who underwent laparoscopic exploration in this multicenter study. Demographics, intraoperative findings (videos and images), and outcomes were retrospectively analyzed. The data of the HSST sign and cholangiography were compared according to the final diagnosis. Then, the diagnostic accuracy of the BA using the HSST sign and cholangiography was validated in other independent cohorts.

RESULTS

A total of 2,216 patients were enrolled in this study. The sensitivity and negative predictive values were both 100% for diagnosing BA based on the HSST sign and cholangiography. The specificity, negative predictive value, and accuracy of the HSST sign (97.2, 99.2, 99.3%) in discriminating BA were significantly higher than operative cholangiography (81.6, 94.9, 95.8; p < 0.001). Moreover, to realize the early diagnosis of BA, the accuracy of the HSST sign in identifying BA was better than cholangiography in the subgroup of neonates (98.7% vs. 95.0%; p = 0.032). Interestingly, 92 non-BA patients without the HSST sign had positive cholangiography. Among them, 28 infants had negative cholangiography when the common bile duct was compressed and 39 patients displayed visible bile ducts due to repeated postoperative biliary irrigation. The other 25 patients (18 with the Alagille syndrome, 5 with progressive familial intrahepatic cholestasis, and 2 with the neonatal hepatitis syndrome) had consistently positive cholangiography. In the independent validation cohort, the diagnostic accuracy of the HSST sign (99.2%) was higher than cholangiography (95.0%, p = 0.012).

CONCLUSION

The laparoscopic HSST sign is superior to cholangiography in the diagnosis of BA in the infants with cholestasis and has advantages in early diagnosis. This method is expected to become a novel shift for diagnosing BA during ongoing laparoscopy.

Value of the International Classification of Diseases code for identifying children with biliary atresia

BACKGROUND

Although identifying cases in large administrative databases may aid future research studies, previous reports demonstrated that the use of the International Classification of Diseases, Tenth Revision (ICD-10) code alone for diagnosis leads to disease misclassification.

PURPOSE

We aimed to assess the value of the ICD-10 diagnostic code for identifying potential children with biliary atresia.

METHODS

Patients aged <18 years assigned the ICD-10 code of biliary atresia (Q44.2) between January 1996 and December 2016 at a quaternary care teaching hospital were identified. We also reviewed patients with other diagnoses of code-defined cirrhosis to identify more potential cases of biliary atresia. A proposed diagnostic algorithm was used to define ICD-10 code accuracy, sensitivity, and specificity.

RESULTS

We reviewed the medical records of 155 patients with ICD-10 code Q44.2 and 69 patients with other codes for biliary cirrhosis (K74.4, K74.5, K74.6). The accuracy for identifying definite/probable/possible biliary atresia cases was 80%, while the sensitivity was 88% (95% confidence interval [CI], 82%-93%). Three independent predictors were associated with algorithm-defined definite/probable/possible cases of biliary atresia: ICD-10 code Q44.2 (odds ratio [OR], 2.90; 95% CI, 1.09-7.71), history of pale stool (OR, 2.78; 95% CI, 1.18-6.60), and a presumed diagnosis of biliary atresia prior to referral to our hospital (OR, 17.49; 95% CI, 7.01-43.64). A significant interaction was noted between ICD-10 code Q44.2 and a history of pale stool (P<0.05). The area under the curve was 0.87 (95% CI, 0.84-0.89).

CONCLUSION

ICD-10 code Q44.2 has an acceptable value for diagnosing biliary atresia. Incorporating clinical data improves the case identification. The use of this proposed diagnostic algorithm to examine data from administrative databases may facilitate appropriate health care allocation and aid future research investigations.

Outcomes of liver transplantation for Alagille syndrome after Kasai portoenterostomy: Alagille Syndrome with agenesis of extrahepatic bile ducts at porta hepatis

BACKGROUND

Alagille syndrome (ALGS) is an autosomal dominant disorder, characterized by a paucity of intrahepatic bile ducts, resulting in significant cholestasis, and peculiar extrahepatic features. Some ALGS patients show a considerable overlap with biliary atresia (BA), and they can undergo Kasai procedure. The purpose of this study is to show the manifestations of BA overlapped ALGS cases in our institution, and to compare the outcomes of ALGS patients following liver transplantation (LT) between those who previously underwent Kasai surgery (ALGS-Kasai group) and those who did not (ALGS-non-Kasai group).

METHODS

Medical records of ALGS patients who underwent LT in Kyoto University Hospital, Japan from January 1992 to March 2018 were analyzed. ALGS diagnosis was determined according to physical, radiologic, and histopathological findings.

RESULTS

Thirty-one patients were ascertained (ALGS-Kasai: 4 males and 5 females vs. ALGS-non-Kasai: 14 males and 8 females, p = 0.43). Of 31 ALGS patients, 96.8% of children had pulmonary artery stenosis, 54.8% showed facial features, 29% revealed skeletal anomalies and 9.7% demonstrated ocular anomalies. The age at LT was significantly younger in ALGS-Kasai than ALGS-non-Kasai group (1.47 [interquartile range (IQR), 0.75-1.92] vs. 5.1 [IQR, 1.4-9.29] years; p = 0.038). Overall patient survival did not significantly differ between ALGS-Kasai (88.9%) and ALGS-non-Kasai patients (86.4%) (p = 0.84). Furthermore, the 1-year, 5-year, and 10-year patient survival rates for ALGS-Kasai group were 100%, 88.9%, and 88.9%, respectively, whereas those for ALGS-non-Kasai group were 90.9%, 90.9%, and 86.4%, respectively, with p-values of 0.36, 0.90, and 0.84, respectively.

CONCLUSIONS

BA overlapped ALGS cases had neonatal progressive cholestasis which prompted Kasai procedure, and early liver dysfunction after Kasai led to performing LT. The ALGS-Kasai patients undergo LT at earlier ages than the ALGS-non-Kasai patients, however, overall patients' survival rates are similar between groups. Overall ALGS patients' survival rate after LT is considered high.

LEVELS OF EVIDENCE

Level III; Case-control study or Retrospective comparative study.

Alagille Syndrome: A Novel Mutation in JAG1 Gene

Alagille syndrome is an autosomal dominant multisystem disorder with variable phenotypic penetrance, caused by heterozygous mutations in JAG1 or NOTCH2, encoding for the components of the Notch signaling pathway. In this paper, we described a novel mutation not yet reported in literature. This 3-years old male child was referred to our Clinical Genetics Unit because of delayed psychomotor development, systolic murmur, dysmorphic facial features, and hypertransaminasemia. The novel JAG1 heterozygous c.2026delT variant in exon 16 was found. JAG1 mutations are classified as protein truncating and non-protein truncating, without any genotype-phenotype correlation. The detected mutation determines a stop codon (p.Cys676AlafsTer67) in the gene sequence, encoding a truncated protein. Our report broadens the spectrum of JAG1 gene mutations.

Outcomes of Alagille syndrome following the Kasai operation: a systematic review and meta-analysis

PURPOSE

Infants with Alagille syndrome (AGS) frequently develop neonatal cholestasis, and some AGS infants who suspected of biliary atresia subsequently undergo the Kasai operation with the diagnosis of biliary atresia. The aim of this study was to investigate the effect of the Kasai operation on liver and patient outcomes among AGS patients, using a meta-analysis.

METHODS

A systematic review and meta-analysis of studies describing the outcomes of AGS patients with/without the Kasai operation were conducted. The analyzed outcomes were liver transplantation, not living with the native liver, and mortality for any reason.

RESULTS

We identified 6 studies (394 AGS patients). All studies were retrospective cohort or case-control studies. The incidences of liver transplantation, not living with the native liver, and mortality were significantly higher in AGS patients who underwent the Kasai operation than in those who did not undergo the Kasai operation (odds ratio: 6.46, 95% CI 3.23-12.89, p < 0.00001; odds ratio: 25.88, 95% CI 2.83-236.84, p < 0.004; odds ratio: 15.05, 95% CI 2.70-83.93, p = 0.002, respectively).

CONCLUSION

The Kasai operation was associated with poor outcomes in AGS patients. It remains unclear if the Kasai operation directly deteriorates liver and patient outcomes in AGS patients.

Cholangiopathies - Towards a molecular understanding

Liver diseases constitute an important medical problem, and a number of these diseases, termed cholangiopathies, affect the biliary system of the liver. In this review, we describe the current understanding of the causes of cholangiopathies, which can be genetic, viral or environmental, and the few treatment options that are currently available beyond liver transplantation. We then discuss recent rapid progress in a number of areas relevant for decoding the disease mechanisms for cholangiopathies. This includes novel data from analysis of transgenic mouse models and organoid systems, and we outline how this information can be used for disease modeling and potential development of novel therapy concepts. We also describe recent advances in genomic and transcriptomic analyses and the importance of such studies for improving diagnosis and determining whether certain cholangiopathies should be viewed as distinct or overlapping disease entities.

A Novel c.91dupG JAG1 Gene Mutation Is Associated with Early Onset and Severe Alagille Syndrome

Alagille syndrome (MIM 118450) is an autosomal dominant disorder characterized by paucity of intrahepatic bile ducts, chronic cholestasis, pulmonary stenosis, butterfly-like vertebrae, posterior embryotoxon, and dysmorphic facial features. Most cases are caused by JAG1 gene mutations. We report the case of a 2-year-old Mexican mestizo patient with Alagille syndrome, having exhibited jaundice and cholestatic syndrome as of three weeks of age. Sequencing analysis of the JAG1 gene revealed the novel heterozygous mutation c.91dupG that originates a truncated protein and therefore a possibly diminished activation of the Notch signaling pathway. The latter may explain the severe phenotype of the patient. Since the mutation was not identified in the parents, it was considered a de novo event, highlighting the importance of molecular diagnosis and genetic counseling. In conclusion, this report widens the spectrum of JAG1 gene mutations associated with Alagille syndrome.

Rapid whole-genome sequencing decreases infant morbidity and cost of hospitalization

Genetic disorders are a leading cause of morbidity and mortality in infants. Rapid whole-genome sequencing (rWGS) can diagnose genetic disorders in time to change acute medical or surgical management (clinical utility) and improve outcomes in acutely ill infants. We report a retrospective cohort study of acutely ill inpatient infants in a regional children's hospital from July 2016-March 2017. Forty-two families received rWGS for etiologic diagnosis of genetic disorders. Probands also received standard genetic testing as clinically indicated. Primary end-points were rate of diagnosis, clinical utility, and healthcare utilization. The latter was modelled in six infants by comparing actual utilization with matched historical controls and/or counterfactual utilization had rWGS been performed at different time points. The diagnostic sensitivity of rWGS was 43% (eighteen of 42 infants) and 10% (four of 42 infants) for standard genetic tests (P = .0005). The rate of clinical utility of rWGS (31%, thirteen of 42 infants) was significantly greater than for standard genetic tests (2%, one of 42; P = .0015). Eleven (26%) infants with diagnostic rWGS avoided morbidity, one had a 43% reduction in likelihood of mortality, and one started palliative care. In six of the eleven infants, the changes in management reduced inpatient cost by $800,000-$2,000,000. These findings replicate a prior study of the clinical utility of rWGS in acutely ill inpatient infants, and demonstrate improved outcomes and net healthcare savings. rWGS merits consideration as a first tier test in this setting.

Direct hyperbilirubinemia in infants with congenital heart disease

BACKGROUND

The association between congenital heart disease (CHD) and infantile cholestasis, a key finding for the diagnosis of biliary atresia (BA), has not been previously investigated. The aim of this study was therefore to investigate the characteristics of direct hyperbilirubinemia (D-HB) in infants with CHD.

METHODS

All neonates admitted to the present hospital and diagnosed with CHD in 2015 and 2016 were included. D-HB (direct bilirubin ≥ 2.0 mg/dL) at ≤60 days of age and other clinical parameters were retrospectively reviewed. Statistical analysis according to presence of D-HB was performed using chi-squared test or Wilcoxon rank sum test.

RESULTS

Seventy-six patients (M:F, 36:40) were included in this study. CHD consisted of ventricular septal defect in 17, patent ductus arteriosus in 10, and other in 49. Thirteen patients (17.1%) had D-HB at ≤60 days of age. Resolution of D-HB (DB < 2.0 mg/dL) occurred in 10 of the 13 patients during the hospital stay, and this occurred in ≤7 days in eight of the 10 patients. Sex, gestational age, birthweight, chromosomal anomalies, need for Fontan operation for CHD repair, and/or cardiac operation were not associated with D-HB at ≤60 days of age.

CONCLUSION

While D-HB was frequently observed in infants with CHD, the majority of D-HB cases resolved spontaneously in ≤1 week. Neonatal clinical parameters or CHD status was not predictive of D-HB. D-HB lasting >1 week in infants with CHD should be evaluated for the cause.

Imaging findings of Alagille syndrome in young infants: differentiation from biliary atresia

OBJECTIVE

To compare the imaging findings using ultrasonography, MR cholangiopancreatography (MRCP), and intraoperative cholangiography (IOC) between Alagille syndrome (AGS) and biliary atresia (BA) in young infants with cholestatic jaundice.

METHODS

The institutional review board approved this retrospective study. Ultrasonography (n = 55), MRCP (n = 33), and IOC (n = 22) studies were performed in 55 infants (all younger than 3 months) with AGS (n = 7) and BA (n = 48). The ultrasound images were reviewed focusing on gallbladder (GB) abnormalities, triangular cord sign, hepatic artery enlargement and signs of portal hypertension. Visualization of the extrahepatic biliary tree was assessed by MRCP and IOC.

RESULTS

Six (86%) AGS patients showed a small GB on ultrasound; this was comparable to that in BA patients (81%, 35/43). The images were negative for triangular cord sign and hepatic artery enlargement in all AGS patients, whereas they were positive in 48% (23/48) (p = 0.034) and 77% (33/43) (p < 0.001) of the BA patients, respectively. Signs of portal hypertension were less common in AGS patients than in BA patients (p = 0.010). Although non-visualization of the extrahepatic biliary tree by MRCP did not differ significantly between patients with AGS and BA, AGS patients showed a higher proportion of visible common bile ducts with IOC, compared to BA patients. The diagnosis of AGS was made in four infants (57%) before ultrasonography, based on extrahepatic manifestations.

CONCLUSION

The small GB visualized on ultrasonography and non-visualization of extrahepatic biliary tree by MRCP commonly occurred in patients with either AGS or BA. However, triangular cord sign, hepatic artery enlargement and signs of portal hypertension onultrasonography and non-visualized common bile duct with IOC were less frequent in AGS patients than in BA patients. Advances in knowledge: Atypical imaging findings for BA should prompt a meticulous evaluation for the extrahepatic manifestations of AGS to avoid possibly harmful surgery.

Initial assessment of the infant with neonatal cholestasis-Is this biliary atresia?

Introduction

Optimizing outcome in biliary atresia (BA) requires timely diagnosis. Cholestasis is a presenting feature of BA, as well as other diagnoses (Non-BA). Identification of clinical features of neonatal cholestasis that would expedite decisions to pursue subsequent invasive testing to correctly diagnose or exclude BA would enhance outcomes. The analytical goal was to develop a predictive model for BA using data available at initial presentation.

Methods

Infants at presentation with neonatal cholestasis (direct/conjugated bilirubin >2 mg/dl [34.2 μM]) were enrolled prior to surgical exploration in a prospective observational multi-centered study (PROBE–NCT00061828). Clinical features (physical findings, laboratory results, gallbladder sonography) at enrollment were analyzed. Initially, 19 features were selected as candidate predictors. Two approaches were used to build models for diagnosis prediction: a hierarchical classification and regression decision tree (CART) and a logistic regression model using a stepwise selection strategy.

Results

In PROBE April 2004-February 2014, 401 infants met criteria for BA and 259 for Non-BA. Univariate analysis identified 13 features that were significantly different between BA and Non-BA. Using a CART predictive model of BA versus Non-BA (significant factors: gamma-glutamyl transpeptidase, acholic stools, weight), the receiver operating characteristic area under the curve (ROC AUC) was 0.83. Twelve percent of BA infants were misclassified as Non-BA; 17% of Non-BA infants were misclassified as BA. Stepwise logistic regression identified seven factors in a predictive model (ROC AUC 0.89). Using this model, a predicted probability of >0.8 (n = 357) yielded an 81% true positive rate for BA; <0.2 (n = 120) yielded an 11% false negative rate.

Conclusion

Despite the relatively good accuracy of our optimized prediction models, the high precision required for differentiating BA from Non-BA was not achieved. Accurate identification of BA in infants with neonatal cholestasis requires further evaluation, and BA should not be excluded based only on presenting clinical features.