Medical management of Alagille syndrome

Alagille Syndrome: Unraveling the Complexities of Genotype-Phenotype Relationships and Exploring Avenues for Improved Diagnosis and Treatment

Alagille syndrome (ALGS) is a rare genetic disorder caused by mutations in the JAG1 and NOTCH2 genes, leading to a wide range of clinical manifestations. This review explores the complex genetic and clinical landscape of ALGS, emphasizing the challenges in understanding genotype-phenotype relationships due to its rarity and the lack of suitable research models. The review projects a clinical overview of the disease, emphasizing the influence of potential gene modifiers on its clinical presentation and the lack of mechanistic studies for over 100 mutations identified in the last 24 years from various populations, representing a significant gap in our current knowledge and advocating for further exploration. The review addresses the diagnostic challenges posed by the variable expressivity and overlapping symptoms of ALGS. It summarizes current treatment options and discusses emerging approaches such as antisense oligonucleotides (ASOs) and gene therapies. Further, the need for improved diagnostic tools, a deeper understanding of the underlying mechanisms, and the development of targeted therapies are emphasized using zebrafish and mice models, as well as genome editing for variant analysis and stem cell organoid models for disease modeling and drug discovery. The importance of cohort-based studies in understanding the natural history and outcomes of ALGS in diverse populations is highlighted. The review concludes by emphasizing the need for multi-disciplinary collaborative research to address the challenges in ALGS diagnosis, prognosis, and treatment, particularly for underrepresented populations.

The burden of Alagille syndrome: uncovering the potential of emerging therapeutics - a comprehensive systematic literature review

Aim: Alagille syndrome (ALGS) is a rare, cholestatic multiorgan disease associated with bile duct paucity, leading to cholestasis. Clinical symptoms of cholestasis include debilitating pruritus, xanthomas, fat-soluble vitamin deficiencies, growth failure, renal disease and impaired health-related quality of life (HRQoL). The main objective was to review the current literature on the epidemiological, clinical, psychosocial and economic burden of ALGS in view of the development of ileal bile acid transporter (IBAT) inhibitors. Methods: Electronic literature databases were searched in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. Results: 330 publications were screened, 119 were relevant: 11 randomized controlled trials (RCTs), 21 non-RCTs, 10 HRQoL studies, two studies assessing cost/resource use and 77 epidemiological studies across several databases through 31 July 2024. Studies confirm that patients with ALGS experience cardiac anomalies, impaired growth, renal disease, poor HRQoL, fat-soluble vitamin deficiencies and debilitating pruritus; until the approval of IBAT inhibitors for the treatment of cholestatic pruritus in patients with ALGS, supportive management was the standard of care. Conclusion: This review confirms the substantial clinical, economic and HRQoL burden associated with ALGS and consolidates current treatment evidence. Data from recent trials in ALGS demonstrate the potential impact of IBAT inhibitors to transform lives by improving cholestatic pruritus symptoms, HRQoL and native liver survival.

Nutrition in Pediatric Liver Disease

In liver disease, there is derangement of appetite, digestion, absorption, assimilation, storage and metabolism of both macro and micronutrients. These derangements have an impact on mortality and morbidity associated with liver diseases. In infants, breast feeds should not be stopped unless there are compelling reasons such as underlying metabolic problem. Parenteral nutrition should be considered only if, oral or nasogastric feeding is not possible. The effect of malnutrition on liver disease and impact of liver failure on nutrition is vicious and nutritional intervention has to be done at the earliest to break that vicious cycle. This chapter gives an overview of nutritional management in acute and chronic liver diseases in children and also its impact on specific clinical scenarios including liver transplantation.

Challenges in pediatric inherited/metabolic liver disease: Focus on the disease spectrum, diagnosis and management of relatively common disorders

The clinical scenario of pediatric liver disease is becoming more intricate due to changes in the disease spectrum, in which an increasing number of inherited/ metabolic liver diseases are reported, while infectious diseases show a decreasing trend. The similar clinical manifestations caused by inherited/metabolic diseases might be under-recognized or misdiagnosed due to nonspecific characteristics. A delayed visit to a doctor due to a lack of symptoms or mild symptoms at an early stage will result in late diagnosis and treatment. Moreover, limited diagnostic approaches, especially liver biopsy, are not easily accepted by pediatric patients, leading to challenges in etiological diagnosis. Liver dysfunction due to inherited/metabolic diseases is often caused by a variety of metabolites, so precision treatment is difficult; symptomatic treatment is a compelling option for inherited disorders.

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.

Alagille Syndrome: A Focused Review on Clinical Features, Genetics, and Treatment

Alagille syndrome (ALGS) is an autosomal dominant disorder caused by pathogenic variants in JAG1 or NOTCH2, which encode fundamental components of the Notch signaling pathway. Clinical features span multiple organ systems including hepatic, cardiac, vascular, renal, skeletal, craniofacial, and ocular, and occur with variable phenotypic penetrance. Genotype-phenotype correlation studies have not yet shown associations between mutation type and clinical manifestations or severity, and it has been hypothesized that modifier genes may modulate the effects of JAG1 and NOTCH2 pathogenic variants. Medical management is supportive, focusing on clinical manifestations of disease, with liver transplant indicated for severe pruritus, liver synthetic dysfunction, portal hypertension, bone fractures, and/or growth failure. New therapeutic approaches are under investigation, including ileal bile acid transporter (IBAT) inhibitors and other approaches that may involve targeted interventions to augment the Notch signaling pathway in involved tissues.

Efficacy and safety of maralixibat treatment in patients with Alagille syndrome and cholestatic pruritus (ICONIC): a randomised phase 2 study

BACKGROUND

Alagille syndrome is a rare genetic disease that often presents with severe cholestasis and pruritus. There are no approved drugs for management. Maralixibat, an apical, sodium-dependent, bile acid transport inhibitor, prevents enterohepatic bile acid recirculation. We evaluated the safety and efficacy of maralixibat for children with cholestasis in Alagille syndrome.

METHODS

ICONIC was a placebo-controlled, randomised withdrawal period (RWD), phase 2b study with open-label extension in children (aged 1-18 years) with Alagille syndrome (NCT02160782). Eligible participants had more than three times the normal serum bile acid (sBA) levels and intractable pruritus. After 18 weeks of maralixibat 380 μg/kg once per day, participants were randomly assigned (1:1) to continue maralixibat or receive placebo for 4 weeks. Subsequently, all participants received open-label maralixibat until week 48. During the long-term extension (204 weeks reported), doses were increased up to 380 μg/kg twice per day. The primary endpoint was the mean sBA change during the RWD in participants with at least 50% sBA reduction by week 18. Cholestastic pruritus was assessed using observer-rated, patient-rated, and clinician-rated 0-4 scales. The safety population was defined as all participants who had received at least one dose of maralixibat. This trial was registered with ClinicalTrials.gov, NCT02160782, and is closed to recruitment.

FINDINGS

Between Oct 28, 2014, and Aug 14, 2015, 31 participants (mean age 5·4 years [SD 4·25]) were enrolled and 28 analysed at week 48. Of the 29 participants who entered the randomised drug withdrawal period, ten (34%) were female and 19 (66%) were male. In the RWD, participants switched to placebo had significant increases in sBA (94 μmol/L, 95% CI 23 to 164) and pruritus (1·7 points, 95% CI 1·2 to 2·2), whereas participants who continued maralixibat maintained treatment effect. This study met the primary endpoint (least square mean difference -117 μmol/L, 95% CI -232 to -2). From baseline to week 48, sBA (-96 μmol/L, -162 to -31) and pruritus (-1·6 pts, -2·1 to -1·1) improved. In participants who continued to week 204 (n=15) all improvements were maintained. Maralixibat was generally safe and well tolerated throughout. The most frequent adverse events were gastrointestinal related. Most adverse events were self-limiting in nature and mild-to-moderate in severity.

INTERPRETATION

In children with Alagille syndrome, maralixibat is, to our knowledge, the first agent to show durable and clinically meaningful improvements in cholestasis. Maralixibat might represent a new treatment paradigm for chronic cholestasis in Alagille syndrome.

FUNDING

Mirum Pharmaceuticals.

Pseudotumor cerebri syndrome in a child with Alagille syndrome: intracranial pressure dynamics and treatment outcome after ventriculoperitoneal shunting

Alagille syndrome (AS) is a rare multisystem disease of the liver, heart, eyes, face, skeleton, kidneys, and vascular system. The occurrence of pseudotumor cerebri syndrome (PTCS) in patients with AS has been reported only exceptionally. Owning to its rarity and a mostly atypical presentation, the diagnosis and natural history of affected patients remain uncertain. We report an atypical case of PTCS in a 4-year-old boy with a known history of AS who presented with bilateral papilledema (PE) on a routine ophthalmological examination. Visual findings deteriorated after treatment with acetazolamide. Continuous intracranial pressure (ICP) monitoring was then utilized to investigate ICP dynamics. Successful treatment with resolution of PE was achieved after ventriculoperitoneal shunting but relapsed due to growth-related dislocation of the ventricular catheter. This report brings new insights into the ICP dynamics and the resulting treatment in this possibly underdiagnosed subgroup of PTCS patients. It also demonstrates that ventriculoperitoneal shunting can provide long-term improvement of symptoms for more than 10 years.

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.

Intracranial Hypertension and Papilledema in a Large Cohort of Pediatric Patients With Alagille Syndrome

AIMS AND BACKGROUND

Ophthalmic abnormalities are amongst the 5 major criteria required for a diagnosis of Alagille syndrome (ALGS), of which embryotoxon, pseudopapilledema, and hypopigmented retinopathy are the most common. Papilledema with or without intracranial hypertension (ICHT) is rarely described. We report 9 pediatric cases of ALGS with bilateral papilledema, 5 of which were diagnosed with ICHT.

METHODS

The ophthalmic data from 85 patients with clinically and/or genetically (n = 37) proven ALGS were reviewed. The study inclusion criteria were a positive diagnosis of ALGS and availability of ophthalmic follow-up data. Ophthalmic data from 40 patients after liver transplantation (LT) for other indications were also analyzed.

RESULTS

Nine (13.0%) of the 69 patients meeting the inclusion criteria had papilledema. The neurological and neuroimaging results in all 9 patients were normal. These 9 patients were categorized into 4 groups: a nontransplant group (n = 1), a group with pretransplant papilledema persistent after LT (n = 2), a group with papilledema occurring after LT with spontaneous resolution (n = 1), and a group with papilledema and signs of ICHT after LT (n = 5). The patients with ICHT were treated with steroids alone (n = 1) or with acetazolamide (n = 4). A ventriculoperitoneal shunt was placed in 2 of the 5 cases because of progressive visual loss. Pseudopapilledema was present in 10 additional patients (14.5%, 10/69). One (2.5%) of the 40 patients without ALGS developed papilledema after LT.

CONCLUSIONS

True ICHT may be underdiagnosed in patients with ALGS. Our findings underscore the need for close ophthalmic follow-up before and after LT in these patients.

Paediatric cholestatic liver disorders for the adult gastroenterologist: a practical guide

With improvements in the outcomes for cholestatic liver diseases that present in childhood, increasing numbers of patients will require ongoing care as adults. The recent advances in management options coupled with the fact that each adult physician will have a limited number of patients with these conditions means there is a need for those in adult services to develop expertise in these conditions that were historically the domain of paediatrics. This review provides an overview of the most common paediatric cholestatic liver diseases and outlines the clinical manifestations and potential complications, and identifies key management issues unique to each condition for effective ongoing care of these patients.

Orthopaedic Manifestations of Alagille Syndrome: A Report of Two Cases and an Updated Literature Review

CASE

Case 1 is a 6-month-old female who presented for evaluation of asymptomatic vertebral anomalies in the setting of jaundice and cardiac murmur; she was diagnosed with Alagille syndrome (AGS). Her spine has been monitored clinically. Case 2 is a 10-year-old female who sustained a pathologic femur fracture in the setting of known AGS, requiring operative stabilization and optimization of her bone mineral density.

CONCLUSIONS

Pediatric orthopaedists care for children with AGS both in management of congenital musculoskeletal anomalies and in treatment of pathologic fractures. Familiarity with the current AGS literature is necessary for provision of optimal multidisciplinary care.

The Roles of Notch Signaling in Liver Development and Disease

The Notch signaling pathway plays major roles in organ development across animal species. In the mammalian liver, Notch has been found critical in development, regeneration and disease. In this review, we highlight the major advances in our understanding of the role of Notch activity in proper liver development and function. Specifically, we discuss the latest discoveries on how Notch, in conjunction with other signaling pathways, aids in proper liver development, regeneration and repair. In addition, we review the latest in the role of Notch signaling in the pathogenesis of liver fibrosis and chronic liver disease. Finally, recent evidence has shed light on the emerging connection between Notch signaling and glucose and lipid metabolism. We hope that highlighting the major advances in the roles of Notch signaling in the liver will stimulate further research in this exciting field and generate additional ideas for therapeutic manipulation of the Notch pathway in liver diseases.

Patient-specific modeling of right coronary circulation vulnerability post-liver transplant in Alagille's syndrome

OBJECTIVES

Cardiac output (CO) response to dobutamine can identify Alagille's syndrome (ALGS) patients at higher risk of cardiovascular complications during liver transplantation. We propose a novel patient-specific computational methodology to estimate the coronary autoregulatory responses during different hemodynamic conditions, including those experienced in a post-reperfusion syndrome (PRS), to aid cardiac risk-assessment.

MATERIAL AND METHODS

Data (pressure, flow, strain and ventricular volumes) from a 6-year-old ALGS patient undergoing catheter/dobutamine stress MRI (DSMRI) were used to parameterize a closed-loop coupled-multidomain (3D-0D) approach consisting of image-derived vascular models of pulmonary and systemic circulations and a series of 0D-lumped parameter networks (LPN) of the heart chambers and the distal arterial and venous circulations. A coronary microcirculation control model (CMCM) was designed to adjust the coronary resistance to match coronary blood flow (and thus oxygen delivery) with MVO2 requirements during Rest, Stress and a virtual PRS condition.

RESULTS

In all three simulated conditions, diastolic dominated right coronary artery (RCA) flow was observed, due to high right ventricle (RV) afterload. Despite a measured 45% increase in CO, impaired coronary flow reserve (CFR) (~1.4) at Stress was estimated by the CMCM. During modeled PRS, a marked vasodilatory response was insufficient to match RV myocardial oxygen requirements. Such exhaustion of the RCA autoregulatory response was not anticipated by the DSMRI study.

CONCLUSION

Impaired CFR undetected by DSMRI resulted in predicted myocardial ischemia in a computational model of PRS. This computational framework may identify ALGS patients at higher risk of complications during liver transplantation due to impaired coronary microvascular responses.

[Biliary atresia and congenital cholestatic syndromes : Characteristics before, after and during transition]

BACKGROUND

A growing number of patients with biliary atresia and congenital cholestatic syndromes are reaching adulthood. These patients often have a number of typical medical features, including specific characteristics of liver transplantation medicine.

OBJECTIVE

What are the special features in the care of adults suffering from liver diseases with manifestation in childhood and adolescence, both before and after liver transplantation (LTX). How does the progression of individual diseases differ depending on age at manifestation? What are specific aspects following pediatric LTX?

PATIENTS AND METHODS

Evaluation and discussion of existing guidelines and recommendations of the individual disciplines and professional societies as well as the current literature. Joint discussion of the recommendations between disciplines (gastroenterology, pediatric gastroenterology, surgery). Inclusion of center-specific experiences with transition from existing transition outpatient departments and training.

RESULTS

The recommendations are presented specifically for each disease. Special features in individual diseases after LTX are also discussed. Diagnosis-independent general treatment concepts for cholestasis and chronic liver disease are presented.

CONCLUSION

Patients with biliary atresia and congenital cholestatic syndromes have a life-long chronic liver disease with and without LTX and require specific medical care. The patients benefit from the pooling of expertise in the individual disciplines.

Alagille Syndrome: An Overview

Alagille syndrome (AGS) is a highly complex, multisystem, autosomal dominant disorder that is caused by a defect in the Notch signaling pathway. This syndrome mainly affects the liver, causing significant cholestasis, which is caused by a paucity of intrahepatic bile ducts. There can be cardiac involvement, including, but not limited to, pulmonary stenosis and tetralogy of Fallot. Patients can also present with butterfly vertebra, ocular issues, and vascular events. Because this syndrome follows an autosomal dominant inheritance, it can have variable expression even in the same family line. For infants in the NICU who have a cardiac defect and persistent hyperbilirubinemia after two weeks of age, genetic testing for AGS should be considered. Early detection and diagnosis can lead to improved outcomes. In this discussion of AGS, the clinical features as well as management are discussed.

Management of cholestatic pruritus in children with Alagille syndrome: Case report and literature review

Alagille syndrome causes intractable pruritus and disfiguring xanthomas because of retained bile acids and cholesterol. Drug therapy in addition to surgical intervention may be effective in many patients in reducing serum bile acids, cholesterol levels, pruritus, and skin xanthomas. In this report, we describe a child with Alagille syndrome who presented with severe pruritus and xanthomas as a consequence of severe hypercholesterolemia and discuss the treatment modalities.

Individualized Medicine in Gastroenterology and Hepatology

After the completion of the Human Genome Project, there has been an acceleration in methodologies on sequencing nucleic acids (DNA and RNA) at a high precision and with ever-decreasing turnaround time and cost. Collectively, these approaches are termed next-generation sequencing and are already affecting the transformation of medical practice. In this symposium article, we highlight the current knowledge of the genetics of selected gastrointestinal tract and liver diseases, namely, inflammatory bowel disease, hereditary cholestatic liver disease, and familial colon cancer syndromes. In addition, we provide a stepwise approach to use next-generation sequencing methodologies for clinical practice with the goal to improve the diagnosis as well as management of and/or therapy of the chosen digestive diseases. This early experience of applying next-generation sequencing in the practice of gastroenterology and hepatology will delineate future best practices in the field, ultimately for the benefit of our patients.

Pediatric Liver Transplantation: Unique Concerns for the Critical Care Team

Liver transplantation originated in children more than 50 years ago, and these youngest patients, while comprising the minority of liver transplant recipients nationwide, can have some of the best and most rewarding outcomes. The indications for liver transplantation in children are generally more diverse than those seen in adult patients. This diversity in underlying cause of disease brings with it increased complexity for all who care for these patients. Children, still being completely dependent on others for survival, also require a care team that is able and ready to work with parents and family in addition to the patient at the center of the process. In this review, we aim to discuss diagnoses of particular uniqueness or importance to pediatric liver transplantation. We also discuss the evaluation of a pediatric patient for liver transplant, the system for allocating them a new liver, and also touch on postoperative concerns that are unique to the pediatric population.

Novel Heterozygous Mutations in JAG1 and NOTCH2 Genes in a Neonatal Patient with Alagille Syndrome

Alagille Syndrome (ALGS) is a rare autosomal dominant disorder that affects multiple organ systems. Cholestasis as a result of a paucity of intrahepatic bile ducts and congenital heart defects are the two most common features of ALGS. We describe a case of ALGS with novel mutations of JAG1 and NOTCH2 genes in a newborn girl with complex congenital heart disease, bilateral dysplastic kidneys, and malrotation with volvulus.

Biliary atresia and other cholestatic childhood diseases: Advances and future challenges

Biliary Atresia and other cholestatic childhood diseases are rare conditions affecting the function and/or anatomy along the canalicular-bile duct continuum, characterised by onset of persistent cholestatic jaundice during the neonatal period. Biliary atresia (BA) is the most common among these, but still has an incidence of only 1 in 10-19,000 in Europe and North America. Other diseases such as the genetic conditions, Alagille syndrome (ALGS) and Progressive Familial Intrahepatic Cholestasis (PFIC), are less common. Choledochal malformations are amenable to surgical correction and require a high index of suspicion. The low incidence of such diseases hinder patient-based studies that include large cohorts, while the limited numbers of animal models of disease that recapitulate the spectrum of disease phenotypes hinders both basic research and the development of new treatments. Despite their individual rarity, collectively BA and other cholestatic childhood diseases are the commonest indications for liver transplantation during childhood. Here, we review the recent advances in basic research and clinical progress in these diseases, as well as the research needs. For the various diseases, we formulate current key questions and controversies and identify top priorities to guide future research.

Alagille syndrome: clinical perspectives

Alagille syndrome is an autosomal dominant, complex multisystem disorder characterized by the presence of three out of five major clinical criteria: cholestasis with bile duct paucity on liver biopsy, congenital cardiac defects (with particular involvement of the pulmonary arteries), posterior embryotoxon in the eye, characteristic facial features, and butterfly vertebrae. Renal and vascular abnormalities can also occur. Inter- and intrafamilial variabilities in the clinical manifestations are common. We reviewed the clinical features and management as well as the molecular basis of Alagille syndrome.

Ultrasonography evaluation of infants with Alagille syndrome: In comparison with biliary atresia and neonatal hepatitis

OBJECTIVE

To evaluate the ultrasonography (US) features of Alagille syndrome (ALGS), as compared with biliary atresia (BA) or neonatal hepatitis (NH).

METHODS

Our study included 23 ALGS, 75 BA and 70 NH patients. The initial US images were retrospectively reviewed for gallbladder (GB) morphology with systemic classification, GB length and luminal area, presence of triangular-cord (TC) sign and hypertrophied hepatic-artery. The presence of anomalies associated with ALGS was evaluated. The diagnostic values of each finding and their combinations were evaluated.

RESULTS

Both ALGS (57%) and BA (79%) were more frequently associated with abnormal GB shapes than NH (19%, all P<0.001). The short and small GBs were more frequently observed in ALGS and BA than in NH (all P<0.001). None in the ALGS and NH showed TC sign, while 41% in the BA did (all P<0.001). Hypertrophied hepatic-artery was noted less frequently in both ALGS (13%) and NH (14%) than in BA (83%, all P<0.001). The combination of US criteria with associated anomalies increased the positive-predictive-value for ALGS.

CONCLUSION

Abnormal shaped GB with absence of the TC sign and hypertrophied hepatic-artery and presence of associated anomalies can be a differential point of ALGS.

Adnexal Incarceration in a Posterior Pelvic Peritoneal Defect Mimics Ovarian Torsion

Surgery for suspected ovarian torsion sometimes reveals unexpected sources of pelvic pain, such as internal hernias, adhesions, or anatomic defects. A 23-year-old nulligravida with Alagille syndrome was taken to the operating room with suspected ovarian torsion. Intraoperatively, the right adnexa bulged out of a right-sided, posterior peritoneal cleft that incarcerated most of the enlarged ovary. No ovarian torsion was identified. The left adnexa appeared to be normal; however, it dwelled within a left-sided posterior peritoneal cleft. The bilateral posterior peritoneal defects that housed the adnexa were likely of congenital etiology. Although adnexal incarceration is a rare finding at surgery for suspected ovarian torsion, it should be part of the differential diagnosis when evaluating acute pelvic pain.

Radiological findings in an ancient Iranian salt mummy (Chehrābād ca. 410-350 BC)

OBJECTIVE

To study pathologies, peri- and postmortal alterations as well as the general preservation state of an ancient Iranian salt mummy.

MATERIALS AND METHODS

Several mummified remains from two different time periods (1500-2500 BP) were found in the Chehrābād salt mine in Iran. Computed tomography was performed on Salt Man #4 (410-350 BC), the best preserved out of the six salt mummies (Siemens, Sensation 16; 512 × 512 matrix; 0.75-5 mm slice thickness, 240-mA tube current, 120-kV tube voltage, and 0.976-mm pixel size).

RESULTS

Radiological analyses showed an excellent state of preservation of an adolescent body. Several normal variants such as aplasia of the frontal sinus as well as a rare congenital deformation of the 5th vertebral body (butterfly vertebra) have been observed. The individual shows multiple fractures, which is consistent with the theory that he died due to a collapse in the ancient salt mine.

CONCLUSIONS

The salt preserved the soft tissue as well as parts of the inner organs remarkably well. However, further investigations including histology are needed to reveal additional details of the health status of this unique salt mummy.

Characteristics and outcome of liver transplantation in children with Alagille syndrome: a single-center experience

BACKGROUND

This study was carried out in Chang Gung Memorial Hospital-Kaohsiung Medical Center, Taiwan, with the aim of reviewing the characteristics and the outcome of liver transplantation (LT) in children with Alagille syndrome (AGS).

METHODS

We performed a retrospective analysis of transplant records of children diagnosed with AGS and undergoing LT between 1987 and 2010.

RESULTS

Nine patients underwent living donor LT. Cholestasis and characteristic facies were seen in all patients. Posterior embryotoxon was seen in 4/9 (44.4%), butterfly vertebrae in 3/9 (33.3%), heart defect (pulmonary stenosis in 2) in 3/9 (33.3%), and renal disease in 2/9 (22.2%) patients. Five cases had cholestasis prior to the age of 60 days, whereas four cases had cholestasis after 60 days of age. Iminodiacetic acid scans showed no excretion of isotope into the bowel in four cases and suggested a false diagnosis of biliary atresia. All patients underwent diagnostic laparotomy and liver biopsy. Results of liver biopsy showed characteristic features of paucity of interlobular bile ducts in all patients. Kasai portoenterostomy was not performed in any patient prior to being referred for LT. The mean age at the time of LT was 4.6 years. The 5-year overall survival rate after living donor LT was 88.9%.

CONCLUSION

Our conclusion is that the clinical features of AGS are informative. In addition, histological confirmation is important in the diagnosis. AGS children with severe liver disease had good prognoses with LT.

Polymorphism analysis and new JAG1 gene mutations of Alagille syndrome in Mexican population

Alagille syndrome is a multisystem disorder with an autosomic dominant pattern of inheritance that affects the liver, heart, eyes, kidneys, skeletal system and presents characteristic facial features. Mutations of the JAG1 gene have been identified in 20–89% of the patients with Alagille syndrome, this gene encodes for a ligand that activates the Notch signaling pathway. In the present study we analyzed 9 Mexican patients with Alagille syndrome who presented the clinical criteria for the classical presentation of the disease. By using the denaturing high performance liquid chromatography mutation analysis we were able to identify different mutations in 7 of the patients (77.77%), importantly, we found 5 novel mutations in JAG1 gene. The allelic frequency distribution of 13 polymorphisms in Mexican population is also reported. The overall results demonstrated an expanding mutational spectrum of JAG1 gene in the Mexican population.

Management of cholestatic pruritus in paediatric patients with alagille syndrome: the King's College Hospital experience

OBJECTIVES

The aims of the study were to perform a retrospective observational review of the present management and outcome of cholestatic pruritus in children with Alagille syndrome (AGS) at King's College Hospital and to use results to inform appropriate guidelines.

METHODS

A retrospective review of 62 patients diagnosed as having AGS from January 1995 to November 2010 treated at King's College Hospital was performed. The departmental database of the Paediatric Liver Centre was searched to identify all patients and the clinical records were then analysed.

RESULTS

Fifty-one (82.3%) patients experienced pruritus and 50 (80.6%) received antipruritic medication. Ursodeoxycholic acid was the most prescribed drug (n = 40). Other drugs prescribed were rifampicin (n = 39), cholestyramine (n = 18), naltrexone (n = 14), alimemazine (n = 13), nonsedating antihistamine agents (n = 7), ondansetron (n = 5), and phenobarbitone (n = 1). Albumin dialysis using the molecular adsorbent recirculation system was used in 1 patient. Sixteen patients (25.8%) were listed for liver transplantation, and 11 had undergone transplantation by November 2010. Patient survival was high at 95.2%. Pruritus resolved permanently in 39.2% (n = 20) of patients. Fifty-five percent (n = 11) of such patients had undergone liver transplantation. Pruritus was controlled by medication in 41.2% (n = 21). Itching remained a significant problem, affecting quality of life in 19.6% of patients (n = 10).

CONCLUSIONS

The management of cholestatic pruritus in AGS is difficult and often suboptimal. Pruritus may remain intractable even with combination medical treatment, and at this stage, surgery or liver transplantation is indicated. At our centre, pruritus was successfully treated in 80.4% of patients with medical and surgical management.

Renal involvement and the role of Notch signalling in Alagille syndrome

Alagille syndrome is an autosomal dominant disorder with variable multisystem organ involvement that is caused by mutations in one of two genes in the Notch signalling pathway, JAG1 or NOTCH2. Alagille syndrome is characterized by bile duct paucity, along with at least three of the following features: cholestasis, cardiac defects, skeletal abnormalities, ocular abnormalities and characteristic facies. However, the clinical features of Alagille syndrome are highly variable, and children or adults may also present with predominantly renal findings and little or no hepatic involvement. Renal involvement occurs in 40% of JAG1-mutation-positive individuals. Renal insufficiency is common and has been specifically reported in children with Alagille syndrome who have end-stage liver disease. The role of NOTCH2 and JAG1 in formation of proximal nephron structures and podocytes might explain the observed phenotypes of renal dysplasia and proteinuria in patients with Alagille syndrome, and renal tubular acidosis may be the result of JAG1 expression in the collecting ducts. Renal vascular hypertension in patients with Alagille syndrome is explained by the widespread vasculopathy and the role of Notch signalling in vascular development. Increased awareness of Alagille syndrome amongst nephrologists may lead to more diagnoses of Alagille syndrome in patients with apparently isolated renal disease.

Genetic determinants of cholestasis

Cholestasis is an overarching term applied for conditions whereby biliary constituents are found in the circulation because of impairment to bile flow. A variety of processes can lead to cholestasis, be they acute or chronic injuries to hepatocytes, cholangiocytes, or the broader biliary tree itself. Such injuries may be driven by rare but highly informative primary genetic abnormalities, or may be seen in individuals with a prior genetic predisposition when confronted by specific environmental challenges such as drug exposure. This review provides a broad outline of some fundamental primary genetic cholestatic syndromes and an update on varying genetic predisposition underlying several acquired cholestatic processes.

Outcomes of liver transplantation for patients with Alagille syndrome: the studies of pediatric liver transplantation experience

Alagille syndrome (ALGS) is a multisystem disorder that manifests as childhood cholestasis. Reports of liver transplantation (LT) for patients with ALGS have come largely from single centers, which have reported survival rates of 57% to 79%. The aim of this study was to determine LT outcomes for patients with ALGS. We performed a retrospective analysis of the Studies of Pediatric Liver Transplantation database, which contains information about 3153 pediatric LT recipients. Data were available for 91 patients with ALGS and for 236 age-matched patients with biliary atresia (BA). The frequency of complex cardiac anomalies was lower in the LT group with ALGS versus published ALGS series (5% versus 13%). The pretransplant glomerular filtration rate (GFR) was <90 mL/minute/1.73 m(2) in 18% of the LT patients with ALGS and in 5% of the LT patients with BA (P < 0.001). The height deficit at listing was worse for the ALGS patients (66%) versus the BA patients (22%). The 1-year patient survival rates were 87% for the ALGS patients and 96% for the BA patients (P = 0.002). The deaths in the ALGS group mostly occurred within the first 30 days. No pretransplant factors associated with death were identified in the ALGS group. A survival analysis revealed that biliary (P = 0.02), vascular (P < 0.001), central nervous system (CNS; P < 0.001), and renal complications (P < 0.001) after LT were associated with death in the ALGS group. Renal insufficiency in the ALGS patients worsened after LT, and at 1 year, GFR was <90 mL/minute/1.73 m(2) in 22% of the LT patients with ALGS but in only 8% of the patients with BA (P = 0.0014). More LT pediatric patients with ALGS either were currently receiving special education (50% versus 30% for BA patients, P = 0.02) or had received special education in the past (60% versus 36%, P = 0.01). Vascular, CNS, and renal complications were increased in the ALGS patients after LT, and this reflected multisystem involvement. Although the 1-year survival rate was modestly lower for the ALGS patients versus the BA patients, the clustering of deaths within the first 30 days is notable and warrants increased vigilance and further investigation.

Biliary disease in children

Biliary diseases in children are infrequent; however, they can be associated with high morbidity and mortality if an accurate diagnosis is not made and adequate treatment provided in a timely fashion. Biliary atresia, choledochal cysts, gallbladder disease, and Alagille syndrome can be associated with similar clinical symptoms, laboratory findings, and radiographic findings, which makes accurate diagnosis difficult. The correct treatment for each of these clinical entities is different and can significantly reduce morbidity and mortality from these diseases. In this article, we discuss the epidemiology, approach to diagnosis, prognosis, and treatment modalities for these four disease processes.

Pathogenesis of cholestatic liver disease and therapeutic approaches

Cholestatic liver disorders are caused by genetic defects, mechanical aberrations, toxins, or dysregulations in the immune system that damage the bile ducts and cause accumulation of bile and liver tissue damage. They have common clinical manifestations and pathogenic features that include the responses of cholangiocytes and hepatocytes to injury. We review the features of bile acid transport, tissue repair and regulation, apoptosis, vascular supply, immune regulation, and cholangiocytes that are associated with cholestatic liver disorders. We now have a greater understanding of the physiology of cholangiocytes at the cellular and molecular levels, as well as genetic factors, repair pathways, and autoimmunity mechanisms involved in the pathogenesis of disease. These discoveries will hopefully lead to new therapeutic approaches for patients with cholestatic liver disease.