Spatially segregated defects and IGF1-responsiveness of hilar and peripheral biliary organoids from a model of Alagille syndrome.

BACKGROUND & AIMS: Alagille syndrome (ALGS) manifests with peripheral intrahepatic bile duct (IHBD) paucity, which can spontaneously resolve. In a model for ALGS, Jag1Ndr/Ndr mice, this occurs with distinct architectural mechanisms in hilar and peripheral IHBDs. Here, we investigated region-specific IHBD characteristics and addressed whether IGF1, a cholangiocyte mitogen that is downregulated in ALGS and in Jag1Ndr/Ndr mice, can improve biliary outcomes. METHODS: Intrahepatic cholangiocyte organoids (ICOs) were derived from hilar and peripheral adult Jag1+/+ and Jag1Ndr/Ndr livers (hICOs and pICOs, respectively). ICOs were grown in Matrigel or microwell arrays, and characterized using bulk RNA sequencing, immunofluorescence, and high throughput analyses of nuclear sizes. ICOs were treated with IGF1, followed by analyses of growth, proliferation, and death. CellProfiler and Python scripts were custom written for image analyses. Key results were validated in vivo by immunostaining. RESULTS: Cell growth assays and transcriptomics demonstrated that Jag1Ndr/Ndr ICOs were less proliferative than Jag1+/+ ICOs. IGF1 specifically rescued survival and growth of Jag1Ndr/Ndr pICOs. Jag1Ndr/Ndr hICOs were the least proliferative, with lower Notch signalling and an enrichment of hepatocyte signatures and IGF uptake/transport pathways. In vitro (Jag1Ndr/Ndr hICOs) and in vivo (Jag1Ndr/Ndr hilar portal tracts) analyses revealed ectopic HNF4a+ hepatocytes. CONCLUSIONS: Hilar and peripheral Jag1Ndr/Ndr ICOs exhibit differences in Notch signalling status, proliferation, and cholangiocyte commitment which may result in cholangiocyte-to-hepatocyte transdifferentiation. While Jag1Ndr/Ndr pICOs can be rescued by IGF1, hICOs are unresponsive, perhaps due to their hepatocyte-like state and/or expression of IGF transport components. IGF1 represents a potential therapeutic for peripheral bile ducts.

Management of adults with Alagille syndrome.

Alagille syndrome (ALGS) is a complex rare genetic disorder that involves multiple organ systems and is historically regarded as a disease of childhood. Since it is inherited in an autosomal dominant manner in 40% of patients, it carries many implications for genetic counselling of patients and screening of family members. In addition, the considerable variable expression and absence of a clear genotype-phenotype correlation, results in a diverse range of clinical manifestations, even in affected individuals within the same family. With recent therapeutic advancements in cholestasis treatment and the improved survival rates with liver transplantation (LT), many patients with ALGS survive into adulthood. Although LT is curative for liver disease secondary to ALGS, complications secondary to extrahepatic involvement remain problematic lifelong. This review is aimed at providing a comprehensive review of ALGS to adult clinicians who will take over the medical care of these patients following transition, with particular focus on certain aspects of the condition that require lifelong surveillance. We also provide a diagnostic framework for adult patients with suspected ALGS and highlight key aspects to consider when determining eligibility for LT in patients with this syndrome.

Non-syndromic bile duct paucity and non-IgE cow's milk allergy: a case report of challenging nutritional management and maltodextrin intolerance.

BACKGROUND: Cholestasis in extremely premature infants (EPI) constitutes a nutritional challenge and maltodextrins have been reported as a possible strategy for hypoglycaemia. We aim to describe the nutritional management of an EPI with non-syndromic bile duct paucity (NSBDP) and feeding intolerance. CASE PRESENTATION: A patient, born at 27 weeks of gestational age, presented cholestatic jaundice at 20 days of life with a clinical picture of NSBDP. Patient's growth was insufficient with formula rich in medium-chain triglyceride (MCT) and branched-chain amino acids (BCAA). Due to frequent fasting hypoglicemic episodes, maltodextrins supplements were provided. He subsequently presented severe abdominal distension and painful crises, which required hospital admission and withdrawal of maltodextrins. Hypercaloric extensively hydrolysed formula provided weight gain, glycemic control, and parallel improvement in cholestasis. CONCLUSIONS: Our case suggests caution with the use of maltodextrins in infants, especially if premature. Commercial preparations for hepatopatic patients contain higher concentrations of MCTs and BCAAs, but personalized strategies must be tailored to each patient.

Alagille syndrome and non-syndromic paucity of the intrahepatic bile ducts.

The observation of bile duct paucity is an important diagnostic finding in children, occurring in roughly 11% of pediatric liver biopsies. Alagille syndrome (ALGS) is a well-defined syndromic form of intrahepatic bile duct paucity that is accompanied by a number of other key features, including cardiac, facial, ocular, and vertebral abnormalities. In the absence of these additional clinical characteristics, intrahepatic bile duct paucity results in a broad differential diagnosis that requires supplementary testing and characterization. Nearly 30 years after ALGS was first described, genetic studies identified a causative gene, JAGGED1, which spearheaded over two decades of research aimed to meticulously delineate the molecular underpinnings of ALGS. These advancements have characterized ALGS as a genetic disease and led to testing strategies that offer the ability to detect a pathogenic genetic variant in almost 97% of individuals with ALGS. Having a molecular understanding of ALGS has allowed for the development of numerous in vitro and in vivo disease models, which have provided hope and promise for the future generation of gene-based and protein-based therapies. Generation of these disease models has offered scientists a mechanism to study the dynamics of bile duct development and regeneration, and in doing so, produced tools that are applicable to the understanding of other congenital and acquired liver diseases.

Deleterious Variants in ABCC12 are Detected in Idiopathic Chronic Cholestasis and Cause Intrahepatic Bile Duct Loss in Model Organisms.

BACKGROUND & AIMS: The etiology of cholestasis remains unknown in many children. We surveyed the genome of children with chronic cholestasis for variants in genes not previously associated with liver disease and validated their biological relevance in zebrafish and murine models. METHOD: Whole-exome (n = 4) and candidate gene sequencing (n = 89) was completed on 93 children with cholestasis and normal serum γ-glutamyl transferase (GGT) levels without pathogenic variants in genes known to cause low GGT cholestasis such as ABCB11 or ATP8B1. CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 genome editing was used to induce frameshift pathogenic variants in the candidate gene in zebrafish and mice. RESULTS: In a 1-year-old female patient with normal GGT cholestasis and bile duct paucity, we identified a homozygous truncating pathogenic variant (c.198delA, p.Gly67Alafs∗6) in the ABCC12 gene (NM_033226). Five additional rare ABCC12 variants, including a pathogenic one, were detected in our cohort. ABCC12 encodes multidrug resistance-associated protein 9 (MRP9) that belongs to the adenosine 5'-triphosphate-binding cassette transporter C family with unknown function and no previous implication in liver disease. Immunohistochemistry and Western blotting revealed conserved MRP9 protein expression in the bile ducts in human, mouse, and zebrafish. Zebrafish abcc12-null mutants were prone to cholangiocyte apoptosis, which caused progressive bile duct loss during the juvenile stage. MRP9-deficient mice had fewer well-formed interlobular bile ducts and higher serum alkaline phosphatase levels compared with wild-type mice. They exhibited aggravated cholangiocyte apoptosis, hyperbilirubinemia, and liver fibrosis upon cholic acid challenge. CONCLUSIONS: Our work connects MRP9 with bile duct homeostasis and cholestatic liver disease for the first time. It identifies a potential therapeutic target to attenuate bile acid-induced cholangiocyte injury.

Neonatal cholestasis can be the first symptom of McCune-Albright syndrome: A case report.

BACKGROUND: McCune-Albright syndrome (MAS) is caused by postzygotic somatic mutations of the GNAS gene. It is characterized by the clinical triad of fibrous dysplasia, café-au-lait skin spots, and endocrinological dysfunction. Myriad complications in MAS, including hepatobiliary manifestations, are also reported. CASE SUMMARY: This is a case of a 4-year-old boy who presented with MAS with neonatal cholestasis. He was suspected to have Alagille syndrome due to neonatal cholestasis with intrahepatic bile duct paucity in liver biopsy, peripheral pulmonary artery stenosis, and renal tubular dysfunction. By the age of 2 years, his cholestatic liver injury gradually improved, but he had repeated left femoral fractures. He did not exhibit endocrinological abnormality or café-au-lait skin spots. However, MAS was suspected due to fibrous dysplasia at the age of 4 years. No mutation was identified in the GNAS gene in the DNA isolated from the peripheral blood, but an activating point mutation (c.601C>T, p.Arg201Cys) was observed in the DNA extracted from the affected bone tissue and that extracted from the formalin-fixed paraffin-embedded liver tissue, which was obtained at the age of 1 mo. CONCLUSION: MAS should be considered as a differential diagnosis for transient cholestasis in infancy.

Alagille Syndrome: Diagnostic Challenges and Advances in Management.

Alagille syndrome (ALGS) is a multisystem disease characterized by cholestasis and bile duct paucity on liver biopsy in addition to variable involvement of the heart, eyes, skeleton, face, kidneys, and vasculature. The identification of JAG1 and NOTCH2 as disease-causing genes has deepened our understanding of the molecular mechanisms underlying ALGS. However, the variable expressivity of the clinical phenotype and the lack of genotype-phenotype relationships creates significant diagnostic and therapeutic challenges. In this review, we provide a comprehensive overview of the clinical characteristics and management of ALGS, and the molecular basis of ALGS pathobiology. We further describe unique diagnostic considerations that pose challenges to clinicians and outline therapeutic concepts and treatment targets that may be available in the near future.

Living donor liver transplantation in Alagille syndrome-Single center experience from south Asia.

To analyze the clinical characteristics and the outcomes of living donor liver transplantation in children with Alagille syndrome (AGS). Clinical data of children with AGS who underwent liver transplantation between July 2009 and May 2019 in our unit were retrospectively analyzed. Primary end-points were patient and graft survival. Ten children with AGS underwent living donor liver transplantation at a median age of 28 months (range, 12-84 months). Jaundice was the most common initial symptom and was noted after a median duration of 20 days after birth (range, 7-60 days). Two patients had undergone Kasai porto-enterostomy for misdiagnosis of biliary atresia. The most common indication for transplantation was severe pruritus with poor quality of life. Explant livers in three children showed cirrhosis with early well-differentiated hepatocellular carcinoma. We have 100% patient and graft survival at a mean follow-up of 32 months (range 3-72 months). The median z-score for weight and height at liver transplantation was -2.66 (range: -6.44 to -0.9) and -3.6 (range: -7.96 to -0.93) while at follow-up was -1.7 (range: -3.4 to -0.35) and -2.1 (range: -3.9 to -1.4), respectively. The estimated glomerular filtration rate was normal pretransplant and follow-up. This is the first series of LDLT for Alagille syndrome in the Indian sub-continent. We report excellent post-transplant outcomes in contrast to outcomes reported from Western literature.

Alagille Syndrome and the Liver: Current Insights.

Alagille syndrome (ALGS) is an autosomal dominant disorder, with multisystem involvement, which usually occurs due to Notch signaling pathway defects, mostly due to JAG1 mutation (ALGS type 1), but rarely due to neurogenic locus notch homolog protein (NOTCH2) mutation (ALGS type 2). It was suspected in cases having at least three out of five major clinical criteria: cholestasis with a paucity of the bile duct, congenital cardiac defects, ocular posterior embryotoxon, typical facial features, and skeletal malformation. Till date, no early predictive marker for hepatic outcome in ALGS has found. No genotypic or, phenotype features or correlation could predict the development of endstage liver disease, which poses a unique management challenge. Cases with progressive liver damage, unremitting cholestasis and intractable pruritus often depend on liver transplantation as last resort. The cardiac, and renal status should be well accessed before liver transplant for the better post-transplantation outcome. Most of the clinical manifestations usually improve the following transplant, except any change in stature. The post liver transplantation outcome was usually comparable with other conditions which require liver transplantation as a last resort, but in this disease the effect of long term immunosuppression on other affected systems not evaluated well till date. Therefore long term post transplant prospective study is required to address these issues. How to cite this article: Singh SP, Pati GK. Alagille Syndrome and the Liver: Current Insights. Euroasian J Hepatogastroenterol, 2018;8(2):140-147.

A case of Alagille syndrome presenting with chronic cholestasis in an adult.

Alagille syndrome (AGS) is a complex multisystem disorder that involves mainly the liver, heart, eyes, face, and skeleton. The main associated clinical features are chronic cholestasis due to a paucity of intrahepatic bile ducts, congenital heart disease primarily affecting pulmonary arteries, vertebral abnormalities, ocular embryotoxon, and peculiar facies. The manifestations generally become evident at a pediatric age. AGS is caused by defects in the Notch signaling pathway due to mutations in JAG1 or NOTCH2. It is inherited in an autosomal dominant pattern with a high degree of penetrance, but variable expressivity results in a wide range of clinical features. Here we report on a 31-year-old male patient who presented with elevated serum alkaline phosphatase and gamma-glutamyl transpeptidase, and was diagnosed with AGS associated with the JAG1 mutation after a comprehensive workup.

A case of Alagille syndrome presenting with chronic cholestasis in an adult

Alagille syndrome (AGS) is a complex multisystem disorder that involves mainly the liver, heart, eyes, face, and skeleton. The main associated clinical features are chronic cholestasis due to a paucity of intrahepatic bile ducts, congenital heart disease primarily affecting pulmonary arteries, vertebral abnormalities, ocular embryotoxon, and peculiar facies. The manifestations generally become evident at a pediatric age. AGS is caused by defects in the Notch signaling pathway due to mutations in JAG1 or NOTCH2. It is inherited in an autosomal dominant pattern with a high degree of penetrance, but variable expressivity results in a wide range of clinical features. Here we report on a 31-year-old male patient who presented with elevated serum alkaline phosphatase and gamma-glutamyl transpeptidase, and was diagnosed with AGS associated with the JAG1 mutation after a comprehensive workup.

A 10-year-old child presenting with syndromic paucity of bile ducts (Alagille syndrome): a case report.

BACKGROUND: Alagille syndrome, a rare genetic disorder with autosomal dominant transmission, manifests with five major features: paucity of interlobular bile ducts, characteristic facies, posterior embryotoxon, vertebral defects, and peripheral pulmonary stenosis. Globally, only 500 cases have so far been reported, with only five cases reported in the Indian subcontinent. Rarely, Alagille syndrome also presents with skin manifestations and early-onset chronic liver disease, which was found in our case. We believe that we report what could be the first case of Alagille syndrome presenting with café au lait spots, as no such published case report could be found in the literature. CASE PRESENTATION: We report an unusual case of childhood cholestatic jaundice with neonatal onset of jaundice. A 10-year-old boy from the Indian subcontinent presented with obstructive jaundice from early infancy. He also had recurrent fractures of his upper limb bones, intermittent bleeding from his nose, productive cough, decreased night vision, hyperpigmented spots over his skin, and progressive enlargement of his abdomen. Histological examination of a liver biopsy specimen revealed a paucity of bile ducts and changes suggestive of chronic liver disease. Our patient was diagnosed with Alagille syndrome and managed conservatively but died 1 year after the final diagnosis. CONCLUSIONS: This particular syndromic form of paucity of bile duct disorder has been rarely reported in the Indian literature so far. Our case is notable because the child had café au lait spots and very early onset of chronic liver disease, which is quite rare in Alagille syndrome. We believe this to be the first case report on Alagille syndrome manifesting with café au lait syndrome and such early onset of chronic liver disease.

An unusual presentation of Kabuki syndrome with orbital cysts, microphthalmia, and cholestasis with bile duct paucity.

Kabuki syndrome (KS) is a rare developmental disorder characterized by multiple congenital malformations, postnatal growth retardation, intellectual disability, and recognizable facial features. It is mainly caused by mutations in either KMT2D or KDM6A. We describe a 14-year-old boy with KS presenting with an unusual combination of bilateral microphthalmia with orbital cystic venous lymphatic malformation and neonatal cholestasis with bile duct paucity, in addition to the typical clinical features of KS. We identified the novel KMT2D mutation c.10588delC, p.(Glu3530Serfs*128) by Mendeliome (Illumina TruSight One®) sequencing, a next generation sequencing panel targeting 4,813 genes linked to human genetic disease. We analyzed the Mendeliome data for additional mutations which might explain the exceptional clinical presentation of our patient but did not find any, leading us to suspect that the above named symptoms might be part of the KMT2D-associated spectrum of anomalies. We thus extend the range of KS-associated malformations and propose a hypothetical connection between KMT2D and Notch signaling. © 2016 Wiley Periodicals, Inc.

Identification of Bile Duct Paucity in Alagille Syndrome: Using CK7 and EMA Immunohistochemistry as a Reliable Panel for Accurate Diagnosis.

Bile duct paucity is the absence or marked reduction in the number of interlobular bile ducts (ILBD) within portal tracts. Its syndromic variant, Alagille syndrome (ALGS), is a multisystem disorder with effects on the liver, cardiovascular system, skeleton, face, and eyes. It is inherited as an autosomal dominant trait due to defects in NOTCH signaling pathway. ALGS is characterized by vanishing ILBD with subsequent chronic obstructive cholestasis in approximately 89% of cases. Cholestasis stimulates formation of new bile ductules through a process of neoductular reaction, making it difficult to evaluate the presence or absence of ILBD. Therefore, finding a method to differentiate clearly between ILBD and the ductular proliferation is essential for accurate diagnosis. A database search identified 28 patients with confirmed diagnosis of ALGS between 1992 and 2014. Additionally, 7 controls were used. A panel of two immunostains, cytokeratin 7 (CK7) and epithelial membrane antigen (EMA), was performed. CK7 highlighted the bile duct epithelium of ILBD and ductular proliferation, while EMA stained only the brush border of ILBD. In our ALGS group, the ratio of EMA-positive ILBD to identified portal tracts was 12.6% (range, 0%-41%). However, this same ratio was 95.0% (range, 90%-100%) among control cases (P < 0.001). We propose a panel of two immunostains, CK7 and EMA, to differentiate ILBD from ductular proliferation in patients with cholestasis. With this panel, identification of bile duct paucity can be achieved. Additional studies, including molecular confirmation and clinical correlation, would provide a definitive diagnosis of ALGS.

JAGGED1 gene variations in Chinese twin sisters with Alagille syndrome.

Variations in the JAGGED1 gene have been found to cause Alagille syndrome. Nevertheless, no particular hotspots in the gene have been found; any part of the entire coding regions for JAGGED1 may be involved. Twin sisters with jaundice visited our hospital and were diagnosed with Alagille syndrome. The gene variations in their JAGGED1 coding sequences were evaluated by complementary DNA sequencing. The 12-month-old twin sisters have broad foreheads, deep-set eyes, pointed chins, and triangular faces with jaundice. Clinical testing showed the presence of posterior embryotoxon, butterfly vertebrae, and atrial septal defect. Biochemical indexes showed cholestasis and liver damage. Three conserved variations were identified within exons 22 (c.2612C>G), 24 (c.2957T>A), and 26 (c.3417T>C) in the JAGGED1 coding sequence. The predicted consequences for c.2612C>G, c.2957T>A, and c.3417T>C were p.Pro871Arg, p.Leu986*, and p.Tyr1139=, respectively. The T to A change in the JAGGED1 coding sequence at 2957 will generate a stop codon and might lead to deletion of amino acid 233 at the C terminal of the JAGGED1 protein. Our data suggest that gene variations of c.2612C>G, c.2957T>A, and c.3417T>C, especially c.2957T>A, might have contributed to the pathogenesis of Alagille syndrome in these Chinese twin sisters and provided new gene evidences for Alagille syndrome.

Clinical features and JAGI gene analysis of 2 cases with Alagille syndrome / 中华实用儿科临床杂志

Objective To carry out the detection of JAGI gene in children with chronic cholestasis and to im-prove the diagnostic level and understanding of Alagille syndrome. Methods Two cases of chronic cholestasis with multiple organ involvement were selected as the research subjects and their clinical data,laboratory test results were col-lected. Two milliliter peripheral intravenous heparin anticoagulan blood was drawn from each patient. All fragments of 26 exons of the JAGI gene were amplified by polymerase chain reaction - sequence based on typing method. Results One patient with chronic cholestasis,heart murmur and dysmorphic face showed bile duct paucity in liver biopsy and a novel heterozygous mutation c. 809 809delG(p. G270Dfs*142)in 6 exon. Abnormal amino acid replaced JAG1 protein and resulted in truncation of the JAG1 protein. The part of epidermal growth factor(EGF)like repeats region loss and the cysteine rich region completely lost. One case with typical chronic cholestasis and dysmorphic face showed a known IVS20 - 2 5delTAAG heterozygous mutation which resulted in splice site changes. Conclusion A novel JAGI gene mutation c. 809 809delG(p. G270Dfs*142)is helpful to screen JAGI gene of Notch signal transduction pathway for chronic cholestasis with multiple organs involvement in children.

Omega-3 Polyunsaturated Fatty Acid for Cholestasis due to Bile Duct Paucity.

Omega (ω)-3 polyunsaturated fatty acids appear to be effective in preventing and treating parenteral nutrition-associated liver disease, and several mechanisms were proposed for this observation. An 8-week-old male infant with cholestasis and acholic stool was diagnosed non-syndromic intrahepatic interlobular bile duct paucity by open-wedge liver biopsy. Initially he was treated with usual supportive medical therapy, including ursodeoxycholic acid. However, the clinical status and laboratory tests did not improve. Omega (ω)-3 polyunsaturated fatty acids (initially intravenous administration and oral administration later), were started and his liver function, including aminotransferase level and bilirubin levels normalized, and the ivory stool color turned green. We report the possible effectiveness of ω-3 polyunsaturated fatty acids as a potent choleretic agent for non-syndromic intrahepatic interlobular bile duct paucity, a very rare structural pediatric hepatic disease.

Omega-3 Polyunsaturated Fatty Acid for Cholestasis due to Bile Duct Paucity / 대한소아소화기영양학회지

Omega (omega)-3 polyunsaturated fatty acids appear to be effective in preventing and treating parenteral nutrition-associated liver disease, and several mechanisms were proposed for this observation. An 8-week-old male infant with cholestasis and acholic stool was diagnosed non-syndromic intrahepatic interlobular bile duct paucity by open-wedge liver biopsy. Initially he was treated with usual supportive medical therapy, including ursodeoxycholic acid. However, the clinical status and laboratory tests did not improve. Omega (omega)-3 polyunsaturated fatty acids (initially intravenous administration and oral administration later), were started and his liver function, including aminotransferase level and bilirubin levels normalized, and the ivory stool color turned green. We report the possible effectiveness of omega-3 polyunsaturated fatty acids as a potent choleretic agent for non-syndromic intrahepatic interlobular bile duct paucity, a very rare structural pediatric hepatic disease.

A Case of Nonsyndromic Intrahepatic Bile Duct Paucity with Congenital Bilateral Vocal Cord Paralysis and 13q Deletion / 대한소아소화기영양학회지

Nonsyndromic intrahepatic bile duct paucity is known to be associated with several kinds of etiology such as infection, chromosomal anomaly, metabolic disease and idiopathic. We report a rare case of intrahepatic bile duct paucity with congenital bilateral vocal cord paralysis and 13q deletion.

Clinical Evaluation of Syndromic and Nonsyndromic Intrahepatic Bile Duct Paucity / 대한소아소화기영양학회지

PURPOSE: The aims of this study were to evaluate the clinical manifestations and prognosis of the syndromic and nonsyndromic intrahepatic bile duct paucity (IHBDP). METHODS: We studied histology of 42 infants with neonatal cholestasis. Fourteen patients were diagnosed as IHBDP. We evaluated the clinical manifestations, courses and prognosis retrospectively. RESULTS: Underlying disease of the 42 infants with neonatal cholestasis were biliary atresia in 23, intrahepatic bile duct paucity in 14 (Alagille syndrome in 4 and nonsyndromic IHBDP in 10), neonatal hepatitis in 5 infants. The mean ratio of the bile ducts per portal tract was 0.087 (range: 0~0.5). The manifestations in 4 patients with Alagille syndrome demonstrated as follows: characteristic face in 3, chronic cholestasis in 4, posterior embryotoxon in 2, vertebral anomalies in 2, peripheral pulmonary stenosis in 2. One of 4 patients of Alagille syndrome improved cholestasis and the other 3 patients were remained their cholestasis and growth retardation. All patients of the nonsyndromic IHBDP were idiopathic. Seven out of 8 patients of nonsyndromic IHBDP showed improvement of cholestasis, and one patient received liver transplantation due to cirrhosis. CONCLUSION: This study suggested that IHBDP should be considered in the differential diagnosis of neonatal cholestasis. The outcome of idiopathic IHBDP was better than predicted.