Chronic cholestasis due to heritable causes is usually diagnosed in childhood. However, many cases can present and survive into adulthood. The time course varies considerably depending on the underlying etiology. Laboratory data usually reveal elevated conjugated hyperbilirubinemia, alkaline phosphatase, and gamma-glutamyl transpeptidase. Patients may be asymptomatic; however, when present, the typical symptoms are pruritus, jaundice, fatigue, and alcoholic stools. The diagnostic methods and management required depend on the underlying etiology. The development of genome-wide associated studies has allowed the identification of specific genetic mutations related to the pathophysiology of cholestatic liver diseases. The aim of this review was to highlight the genetics, clinical pathophysiology, presentation, diagnosis, and treatment of heritable etiologies of chronic cholestatic liver disease.

Alagille syndrome is an autosomal dominant and multisystemic disease that generally manifests itself with intrahepatic bile ducts paucity, chronic cholestasis, xanthomas and with other less frequent clinical manifestations such as congenital heart disease, skeletal abnomalies, ophthalmic, vascular, renal and growth failure. Symptoms can be subclinical or very severe. Is caused by various genetic mutations and the majority of patients have a detectable mutation in JAG1 (90%), the remainder have mutations in NOTCH2. The diagnosis is molecular and the incidence is approximately 1 in 30,000 - 50.000. Patient management can be very complex and treatment depends on the district affected and on the symptoms. In more serious cases, with terminal liver disease, liver transplantation is used. We describe a case with main bile duct hypoplasia, intrahepatic bile ducts paucity, cholestasis and gallbladder dimorphism associated with renal malrotation and butterfly vertebrae.

UNASSIGNED: Alagille syndrome (ALGS) is a multisystem disorder involving at least three systems among the liver, heart, skeleton, face, and eyes. Common cardiac associations include pulmonary artery stenosis/atresia, atrial septal defect (ASD), ventricular septal defect (VSD) and tetralogy of fallot (ToF). Coarctation of aorta (CoA), renal and intracranial arteries are commonly involved vessels in Alagille syndrome. We present two cases with rare cardiovascular manifestations of Alagille syndrome. Case description.
UNASSIGNED: A 25-year-old female with a history of Alagille syndrome presented to the cardiologist office for progressive exertional dyspnoea, orthopnoea, and palpitations. She was tachycardiac on examination and had an apical diastolic rumble. A transthoracic echocardiogram (TTE) showed a left ventricular ejection fraction (LVEF) of 60% and parachute mitral valve (PMV) with severe mitral stenosis. A transoesophageal echocardiogram (TOE) showed insertion of chordae into the anterolateral papillary muscle, severe mitral stenosis with a valve area of 0.7 cm. She was referred to a congenital heart disease specialist and underwent robotic mitral valve replacement with improvement in her symptoms.
UNASSIGNED: A 27-year-old female with known Alagille syndrome and resistant hypertension presented to the cardiologist office due to progressive exertional dyspnoea for a year. She was hypertensive and had a new 2/6 systolic ejection murmur along the left upper sternal border. TTE revealed an LVEF of 60% and pulmonary artery pressure of 19 mmHg. A CoA was suspected distal to the left subclavian artery due to a peak gradient of 38 mmHg. Cardiac magnetic resonance (CMR) imaging ruled out CoA, and diffuse narrowing of the descending thoracic aorta measuring 13-14 mm in diameter was noted. The patient was referred to a congenital heart disease specialist for further management.
UNASSIGNED: PMV presenting as mitral stenosis and mid-aortic syndrome are not commonly described anomalies in association with Alagille syndrome. TTE, TOE and CMR played a key role in diagnosis and management of these patients.
CONCLUSIONS: Alagille syndrome (ALGS) is a complex multisystem disorder involving the liver, heart, skeleton, face, and eyes. Cardiovascular involvement occurs in up to 95% of the patients.Common cardiac associations include pulmonary artery stenosis/atresia, atrial septal defect (ASD), ventricular septal defect (VSD) and tetralogy of fallot (ToF).A parachute mitral valve (PMV) presenting as mitral stenosis and mid-aortic syndrome is not commonly described anomalies in association with ALGS. Here, we present such rare cases.

Alagille syndrome (ALGS) is an autosomal dominant, multisystemic disorder due to haploinsufficiency in JAG1 or less frequently, mutations in NOTCH2. The disease has been difficult to diagnose and treat due to variable expression. The generation of this iPSC line (TRNDi036-A) carrying a heterozygous mutation (p.Cys693*) in the JAG1 gene provides a means of studying the disease and developing novel therapeutics towards patient treatment.

Alagille syndrome (AGS) is a genetic disorder due to mutations in the JAGGED 1 or NOTCH 2 genes leading to multisystemic manifestations. Though these patients are at risk of developing various liver tumours, no cases of hepatoblastoma among young children with cirrhosis in AGS have been reported. We report a male toddler, with cirrhosis due to AGS who developed a hepatoblastoma. He underwent a liver transplant for decompensated chronic liver disease with marked pruritus, very high alpha-fetoprotein levels and malignant liver lesions on positron emission tomography CT. His explant histology revealed a paucity of bile ducts and liver lesions turned out to be hepatoblastoma for which he received postoperative chemotherapy. The genetic testing sent before transplantation confirmed the clinical diagnosis of AGS. Hepatoblastoma should be suspected in any child with AGS presenting with a right upper quadrant mass even in the setting of chronic liver disease.

Coronary bifurcation lesions and treatment with two-stent techniques have been developed, including the double kissing (DK) crush technique. The use of this technique in children or noncoronary vessels, including pulmonary arteries, has not been described. We present a 12-year-old girl with Alagille syndrome, a ventricular septal defect (VSD), and complex bilateral pulmonary artery (PA) stenoses who is status post six catheterizations for PA angioplasty and stenting to improve her marked right ventricular hypertension. With collaboration between the congenital and structural teams, she successfully underwent the DK crush technique for a complex lesion in her PA. This improved pulmonary flow and allowed for successful surgical VSD closure.

Alagille Syndrome (ALGS) is a complex genetic disorder characterized by cholestasis, congenital cardiac anomalies, and butterfly vertebrae. The variable phenotypic expression of ALGS can lead to challenges in accurately diagnosing affected infants, potentially resulting in misdiagnoses or underdiagnoses. This study highlights novel JAG1 gene mutations in two cases of ALGS. The first case with a novel p.Pro325Leufs*87 variant was diagnosed at 2 months of age and exhibited a favorable prognosis and an unexpected manifestation of congenital hypothyroidism. Before the age of 2, the second patient was incorrectly diagnosed with liver structural abnormalities, necessitating extensive treatment. In addition, he exhibited delays in language acquisition that may have been a result of SNAP25 haploinsufficiency. The identification of ALGS remains challenging, highlighting the importance of early detection and genetic testing for effective patient management. The variant p.Pro325Leufs*87 is distinct from reported variants linked to congenital hypothyroidism in ALGS patients, thereby further confirming the clinical and genetic complexity of ALGS. This emphasizes the critical need for individualized and innovative approaches to diagnosis and medical interventions, uniquely intended to address the complexity of this syndrome.

BACKGROUND: Mitochondrial hepatopathies (MHs) are primary mitochondrial genetic disorders that can present as childhood liver disease. No recognized biomarkers discriminate MH from other childhood liver diseases. The protein biomarkers growth differentiation factor 15 (GDF15) and fibroblast growth factor 21 (FGF21) differentiate mitochondrial myopathies from other myopathies. We evaluated these biomarkers to determine if they discriminate MH from other liver diseases in children.
METHODS: Serum biomarkers were measured in 36 children with MH (17 had a genetic diagnosis); 38 each with biliary atresia, α1-antitrypsin deficiency, and Alagille syndrome; 20 with NASH; and 186 controls.
RESULTS: GDF15 levels compared to controls were mildly elevated in patients with α1-antitrypsin deficiency, Alagille syndrome, and biliary atresia-young subgroup, but markedly elevated in MH (p<0.001). FGF21 levels were mildly elevated in NASH and markedly elevated in MH (p<0.001). Both biomarkers were higher in patients with MH with a known genetic cause but were similar in acute and chronic presentations. Both markers had a strong performance to identify MH with a molecular diagnosis with the AUC for GDF15 0.93±0.04 and for FGF21 0.90±0.06. Simultaneous elevation of both markers >98th percentile of controls identified genetically confirmed MH with a sensitivity of 88% and specificity of 96%. In MH, independent predictors of survival without requiring liver transplantation were international normalized ratio and either GDF15 or FGF21 levels, with levels <2000 ng/L predicting survival without liver transplantation (p<0.01).
CONCLUSIONS: GDF15 and FGF21 are significantly higher in children with MH compared to other childhood liver diseases and controls and, when combined, were predictive of MH and had prognostic implications.

OBJECTIVE: Alagille syndrome (ALGS) is characterized by chronic cholestasis with associated pruritus and extrahepatic anomalies. Maralixibat, an ileal bile acid transporter inhibitor, is an approved pharmacologic therapy for cholestatic pruritus in ALGS. Since long-term placebo-controlled studies are not feasible or ethical in children with rare diseases, a novel approach was taken comparing 6-year outcomes from maralixibat trials with an aligned and harmonized natural history cohort from the G lobal AL agille A lliance (GALA) study.
RESULTS: Maralixibat trials comprise 84 patients with ALGS with up to 6 years of treatment. GALA contains retrospective data from 1438 participants. GALA was filtered to align with key maralixibat eligibility criteria, yielding 469 participants. Serum bile acids could not be included in the GALA filtering criteria as these are not routinely performed in clinical practice. Index time was determined through maximum likelihood estimation in an effort to align the disease severity between the two cohorts with the initiation of maralixibat. Event-free survival, defined as the time to first event of manifestations of portal hypertension (variceal bleeding, ascites requiring therapy), surgical biliary diversion, liver transplant, or death, was analyzed by Cox proportional hazards methods. Sensitivity analyses and adjustments for covariates were applied. Age, total bilirubin, gamma-glutamyl transferase, and alanine aminotransferase were balanced between groups with no statistical differences. Event-free survival in the maralixibat cohort was significantly better than the GALA cohort (HR, 0.305; 95% CI, 0.189-0.491; p <0.0001). Multiple sensitivity and subgroup analyses (including serum bile acid availability) showed similar findings.
CONCLUSIONS: This study demonstrates a novel application of a robust statistical method to evaluate outcomes in long-term intervention studies where placebo comparisons are not feasible, providing wide application for rare diseases. This comparison with real-world natural history data suggests that maralixibat improves event-free survival in patients with ALGS.

Alagille syndrome and progressive familial intrahepatic cholestasis are conditions that can affect multiple organs. Advancements in molecular testing have aided in the diagnosis of both. The impairment of normal bile flow and secretion leads to the various hepatic manifestations of these diseases. Medical management of Alagille syndrome and progressive familial intrahepatic cholestasis remains mostly targeted on supportive care focusing on quality of life, cholestasis, and fat-soluble vitamin deficiency. The most difficult therapeutic issue is typically related to pruritus, which can be managed by various medications such as ursodeoxycholic acid, rifampin, cholestyramine, and antihistamines. Surgical operations were previously used to disrupt enterohepatic recirculation, but recent medical advancements in the use of ileal bile acid transport inhibitors have shown great efficacy for the treatment of pruritus in both Alagille syndrome and progressive familial intrahepatic cholestasis.