Biliary disease progression in childhood onset autoimmune liver disease: A 30-year follow-up into adulthood

Background & Aims

Long-term follow-up studies of paediatric onset autoimmune liver disease (AILD) are invaluable in helping better understand the clinical course of disease. In day-to-day practice clinicians struggle with disease definitions whilst patients and parents lack clear prognostic information.

Methods

The clinical progression of 159 patients with childhood onset AILD between June 1990 and December 2013 was reviewed, capturing data up to adulthood (ending May 2021).

Results

Presentation with autoimmune hepatitis (AIH) was dominant (n = 119); biliary presentations accounted for 25%. During follow up, biliary disease progression confirmed by cholangiography and/or liver histology was observed frequently: 19.8% (20/101) patients with childhood onset AIH type 1 (AIH-1) developed biliary features by adulthood and of these 50% phenotypically transitioned to primary sclerosing cholangitis (PSC); the remaining transitioned to an overlap disease phenotype. No patients with AIH type 2 developed biliary progression. Two-thirds of patients with overlap features (14/21) in childhood had phenotypically progressed to PSC by adulthood. Approximately 43% (6/14) of AIH-1 patients requiring a liver transplant in adulthood had explant evidence of biliary disease compared with 11% (1/9) in childhood, whereas 35.7% (5/14) of patients had histology diagnostic of PSC in their explant liver and 7.1% (1/14) had overlap features. All patients with biliary phenotypes (PSC, autoimmune sclerosing cholangitis, overlap) who required a transplant (n = 18) were found to have explant histology consistent with PSC. Twelve of 14 patients with biliary progression developed ulcerative colitis during follow-up with 92% progressing to PSC.

Conclusions

Three decades of follow-up demonstrated how children presenting with AILD had a significant risk of clinical transformation to PSC. Biliary progression was significantly associated with the development of inflammatory bowel disease.

Impact and implications

Childhood onset autoimmune liver disease remains very impactful for patients and families. Disease nomenclature can however be confusing. Long-term follow up studies as children become adults is important to help understand how and why disease behaves over time. Understanding more about the long-term course of childhood autoimmune liver disease will help patients, families and doctors striving to improve care and reduce poor clinical outcomes. We followed over 150 patients with childhood onset autoimmune liver diseases into adulthood. We found that amongst patients with classical autoimmune hepatitis, 1 in 5 developed biliary disease over time, mostly consisting of primary sclerosing cholangitis. This was associated with developing inflammatory bowel disease. Our study design was retrospective and has relevant limitations. Defining phenotypes of autoimmune liver diseases is difficult and there is insufficient consensus, especially between adult and childhood physicians. Our data confirms the critical importance of careful long-term follow-up of patients, including safe transition to adult care, as well as robustly demonstrates, using real-world data, how disease nature can change over time. Our study affirms the need for investment in prospective cohort studies.

Event-free survival of maralixibat-treated patients with Alagille syndrome compared to a real-world cohort from GALA

BACKGROUND AND AIMS

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.

APPROACH AND 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.

Long-term Outcome of Asymptomatic Patients With Graft Fibrosis in Protocol Biopsies After Pediatric Liver Transplantation

BACKGROUND

The histological prevalence of allograft fibrosis in asymptomatic children after liver transplantation (LT) is well documented. However, long-term graft and patient survival remain unclear. This retrospective multicenter study aims to determine the prevalence of allograft fibrosis and analyze the long-term outcome for patients transplanted in childhood.

METHODS

We reviewed clinical data of children who had undergone 10-y protocol liver biopsies. We excluded patients with autoimmune hepatitis, primary sclerosing cholangitis, hepatitis B or C, and retransplantation. In total, 494 patients transplanted in childhood across 12 international transplant centers were included. We evaluated the development of fibrosis by comparing the results with biopsies obtained 5 and 15 y post-LT. Histological findings were correlated with graft and patient survival up to 20 y post-LT.

RESULTS

In the 10-y biopsies, periportal or pericentral fibrosis was observed in 253 patients (51%), 87 (18%) had bridging fibrosis, 30 (6%) had cirrhosis, and 124 (25%) had no fibrosis. The prevalence and stage of graft fibrosis significantly progressed from 5 to 10 y. At 10 y, the severity of fibrosis correlated significantly with inflammation. Patients with graft cirrhosis in the 10-y biopsy were more likely to die or require retransplantation subsequently ( P = 0.027).

CONCLUSIONS

At 10 y post-LT, most patients transplanted in childhood developed fibrosis, based on the protocol liver biopsies. Although mild-to-moderate graft fibrosis did not largely affect patient or graft survival up to 20 y post-LT, this progressive fibrosis finding has substantial implications for developing cirrhosis and portal hypertension in adult care.

Paediatric acute hepatitis of unknown aetiology: a national investigation and adenoviraemia case-control study in the UK

BACKGROUND

An increase in acute severe hepatitis of unknown aetiology in previously healthy children in the UK in March, 2022, triggered global case-finding. We aimed to describe UK epidemiological investigations of cases and their possible causes.

METHODS

We actively surveilled unexplained paediatric acute hepatitis (transaminase >500 international units per litre) in children younger than 16 years presenting since Jan 1, 2022, through notifications from paediatricians, microbiologists, and paediatric liver units; we collected demographic, clinical, and exposure information. Then, we did a case-control study to investigate the association between adenoviraemia and other viruses and case-status using multivariable Firth penalised logistic regression. Cases aged 1-10 years and tested for adenovirus were included and compared with controls (ie, children admitted to hospital with an acute non-hepatitis illness who had residual blood samples collected between Jan 1 and May 28, 2022, and without known laboratory-confirmed diagnosis or previous adenovirus testing). Controls were frequency-matched on sex, age band, sample months, and nation or supra-region with randomised selection. We explored temporal associations between frequency of circulating viruses identified through routine laboratory pathogen surveillance and occurrence of cases by linear regression. SARS-CoV-2 seropositivity of cases was examined against residual serum from age-matched clinical comparison groups.

FINDINGS

Between Jan 1 and July 4, 2022, 274 cases were identified (median age 3 years [IQR 2-5]). 131 (48%) participants were male, 142 (52%) were female, and one (<1%) participant had sex data unknown. Jaundice (195 [83%] of 235) and gastrointestinal symptoms (202 [91%] of 222) were common. 15 (5%) children required liver transplantation and none died. Adenovirus was detected in 172 (68%) of 252 participants tested, regardless of sample type; 137 (63%) of 218 samples were positive for adenovirus in the blood. For cases that were successfully genotyped, 58 (81%) of 72 had Ad41F, and 57 were identified as positive via blood samples (six of these were among participants who had undergone a transplant). In the case-control analysis, adenoviraemia was associated with hepatitis case-status (adjusted OR 37·4 [95% CI 15·5-90·3]). Increases in the detection of adenovirus from faecal samples, but not other infectious agents, in routine laboratory pathogen surveillance correlated with hepatitis cases 4 weeks later, which independently suggested an association (β 0·06 [95% CI 0·02-0·11]). No association was identified for SARS-CoV-2 antibody seropositivity.

INTERPRETATION

We observed an association between adenovirus 41F viraemia and paediatric acute hepatitis. These results can inform diagnostic testing recommendations, clinical management, and exploratory in vitro or clinical studies of paediatric acute hepatitis of unknown aetiology. The role of potential co-factors, including other viruses and host susceptibility, requires further investigation.

FUNDING

None.

Case report: Acute liver failure in children and the human herpes virus 6-? A factor in the recent epidemic

The 2022 worldwide epidemic of acute hepatitis and liver failure in young children has led to a focus on unusual causes for childhood acute hepatitis. In the UK epidemic, human herpes virus subtype 6B (HHV-6B) was detected along with adenovirus subtype-41F in severely affected children, especially in those requiring liver transplantation (LT). The lifting of COVID lock-down measures has coincided with the rise in these common childhood infections with a higher than expected rate of systemic complications. The sudden exposure of young children to common childhood infections from which they were protected during the pandemic may have induced an abnormal immune mediated response potentiated by multiple pathogen exposure. Primary HHV-6 infection is one such common childhood infection. Classically known as Roseola infantum due to the appearance of a widespread erythematous rash on fever subsidence (exanthema subitem), it has a peak incidence of 6-12 months of age and almost all children will have been infected by age 2. It is the virus most frequently associated with febrile convulsions but the more serious complications of hepatitis and liver failure are rare. We report on the historic cases of three female infants who had suspected primary HHV-6B infection, acute hepatitis and rapid progression to acute liver failure (ALF) requiring LT. Appearances of their native liver were identical to those described in children in the recent hepatitis epidemic. Deteriorating clinical trajectories of recurrent graft hepatitis and rejection-like episodes followed and all three succumbed to graft failure with HHV-6B detected posthumously in their liver allografts. Our case series and the serious complications observed with the recent rise in common childhood infections is a reminder that these routinely encountered pathogens can be deadly especially in the young immunologically untrained. We advocate for HHV-6 to be screened for routinely in children with acute hepatitis and the use of effective HHV-6 anti-viral prophylaxis to prevent recurrence post-transplant.

Natural history of liver disease in a large international cohort of children with Alagille syndrome: Results from the GALA study

BACKGROUND AND AIMS

Alagille syndrome (ALGS) is a multisystem disorder, characterized by cholestasis. Existing outcome data are largely derived from tertiary centers, and real-world data are lacking. This study aimed to elucidate the natural history of liver disease in a contemporary, international cohort of children with ALGS.

APPROACH AND RESULTS

This was a multicenter retrospective study of children with a clinically and/or genetically confirmed ALGS diagnosis, born between January 1997 and August 2019. Native liver survival (NLS) and event-free survival rates were assessed. Cox models were constructed to identify early biochemical predictors of clinically evident portal hypertension (CEPH) and NLS. In total, 1433 children (57% male) from 67 centers in 29 countries were included. The 10 and 18-year NLS rates were 54.4% and 40.3%. By 10 and 18 years, 51.5% and 66.0% of children with ALGS experienced ≥1 adverse liver-related event (CEPH, transplant, or death). Children (>6 and ≤12 months) with median total bilirubin (TB) levels between ≥5.0 and <10.0 mg/dl had a 4.1-fold (95% confidence interval [CI], 1.6-10.8), and those ≥10.0 mg/dl had an 8.0-fold (95% CI, 3.4-18.4) increased risk of developing CEPH compared with those <5.0 mg/dl. Median TB levels between ≥5.0 and <10.0 mg/dl and >10.0 mg/dl were associated with a 4.8 (95% CI, 2.4-9.7) and 15.6 (95% CI, 8.7-28.2) increased risk of transplantation relative to <5.0 mg/dl. Median TB <5.0 mg/dl were associated with higher NLS rates relative to ≥5.0 mg/dl, with 79% reaching adulthood with native liver ( p < 0.001).

CONCLUSIONS

In this large international cohort of ALGS, only 40.3% of children reach adulthood with their native liver. A TB <5.0 mg/dl between 6 and 12 months of age is associated with better hepatic outcomes. These thresholds provide clinicians with an objective tool to assist with clinical decision-making and in the evaluation of therapies.

Diagnosing Acute Cellular Rejection after Paediatric Liver Transplantation-Is There Room for Interleukin Profiles?

BACKGROUND

The current gold standard to diagnose T-cell-mediated acute rejection (TCMR) requires liver histology. Using data from the ChilSFree study on immune response after paediatric liver transplantation (pLT), we aimed to assess whether soluble cytokines can serve as an alternative diagnostic tool in children suspected to have TCMR.

METHODS

A total of n = 53 blood samples obtained on the day of or up to 3 days before liver biopsy performed for suspected TCMR at median 18 days (range 7-427) after pLT in n = 50 children (38% female, age at pLT 1.8 (0.5-17.5) years) were analysed for circulating cytokine levels using Luminex-based Multiplex technology. Diagnostic accuracy of cytokine concentrations was assessed using a multivariable model based on elastic net regression and gradient boosting machine analysis.

RESULTS

TCMR was present in 68% of biopsies. There was strong evidence that patients with TCMR had increased levels of soluble CXCL8, CXCL9, CXCL10, IL-16, IL-18, HGF, CCL4, MIF, SCGF-β, and HGF before biopsy. There was some evidence for increased levels of sCD25, ICAM-1, IL-6, IL-3, and CCL11. Diagnostic value of both single cytokine levels and a combination of cytokines and clinical markers was poor, with AUROCs not exceeding 0.7.

CONCLUSION

Patients with TCMR showed raised levels of cytokines and chemokines reflective of T-cell activation and chemotaxis. Despite giving insight into the mechanisms of TCMR, the diagnostic value of soluble cytokines for the confirmation of TCMR in a clinical scenario of suspected TCMR is poor.

Prognosis of Children Undergoing Liver Transplantation: A 30-Year European Study

OBJECTIVES

The European Liver Transplant Registry has been collecting data on virtually all pediatric liver transplant (PLT) procedures in Europe since 1968. We analyzed patient outcome over time and identified parameters associated with long-term patient outcome.

METHODS

Participating centers and European organ-sharing organizations provided retrospective data to the European Liver Transplant Registry. To identify trends, data were grouped into consecutive time spans: era A: before 2000, era B: 2000 to 2009, and the current era, era C: since 2010.

RESULTS

From June 1968 until December 2017, 16 641 PLT were performed on 14 515 children by 133 centers. The children <7 years of age represented 58% in era A, and 66% in the current era (P <.01). The main indications for PLT were congenital biliary diseases (44%) and metabolic diseases (18%). Patient survival at 5 years is currently 86% overall and 97% in children who survive the first year after PLT. The survival rate has improved from 74% in era A to 83% in era B and 85% in era C (P <.0001). Low-volume centers (<5 PLT/year) represented 75% of centers but performed only 19% of PLT and were associated with a decreased survival rate. In the current era, however, survival rates has become irrespective of volume. Infection is the leading cause of death (4.1%), followed by primary nonfunction of the graft (1.4%).

CONCLUSIONS

PLT has become a highly successful medical treatment that should be considered for all children with end-stage liver disease. The main challenge for further improving the prognosis remains the early postoperative period.

Standardizing the histological assessment of late posttransplantation biopsies from pediatric liver allograft recipients

Excellent short-term survival after pediatric liver transplantation (LT) has shifted attention toward the optimization of long-term outcomes. Despite considerable progress in imaging and other noninvasive modalities, liver biopsies continue to be required to monitor allograft health and to titrate immunosuppression. However, a standardized approach to the detailed assessment of long-term graft histology is currently lacking. The aim of this study was to formulate a list of histopathological features relevant for the assessment of long-surviving liver allograft health and to develop an approach for assessing the presence and severity of these features in a standardized manner. Whole-slide digital images from 31 biopsies obtained ≥4 years after transplantation to determine eligibility for an immunosuppression withdrawal trial were selected to illustrate a range of typical histopathological findings seen in children with clinically stable grafts, including those associated with alloantibodies. Fifty histological features were independently assessed and, where appropriate, scored semiquantitatively by six pathologists to determine inter- and intraobserver reproducibility of the histopathological features using unweighted and weighted kappa statistics; the latter metric enabled distinction between minor and major disagreements in parameter severity scoring. Weighted interobserver kappa statistics showed a high level of agreement for various parameters of inflammation, interface activity, fibrosis, and microvascular injury. Intraobserver agreement for these features was even more substantial. The results of this study will help to standardize the assessment of biopsies from long-surviving liver allografts, aid the recognition of important histological features, and facilitate international comparisons and clinical trials aiming to improve outcomes for children undergoing LT.

Variants in mitochondrial amidoxime reducing component 1 and hydroxysteroid 17-beta dehydrogenase 13 reduce severity of nonalcoholic fatty liver disease in children and suppress fibrotic pathways through distinct mechanisms

Genome-wide association studies in adults have identified variants in hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13) and mitochondrial amidoxime reducing component 1 (MTARC1) as protective against nonalcoholic fatty liver disease (NAFLD). We aimed to test their association with pediatric NAFLD liver histology and investigate their function using metabolomics. A total of 1450 children (729 with NAFLD, 399 with liver histology) were genotyped for rs72613567T>TA in HSD17B13, rs2642438G>A in MTARC1, and rs738409C>G in patatin-like phospholipase domain-containing protein 3 (PNPLA3). Genotype-histology associations were tested using ordinal regression. Untargeted hepatic proteomics and plasma lipidomics were performed in a subset of children. We found rs72613567T>TA in HSD17B13 to be associated with lower odds of NAFLD diagnosis (odds ratio, 0.7; 95% confidence interval, 0.6-0.9) and a lower grade of portal inflammation (p < 0.001). rs2642438G>A in MTARC1 was associated with a lower grade of hepatic steatosis (p = 0.02). Proteomics found reduced expression of HSD17B13 in carriers of the protective -TA allele. MTARC1 levels were unaffected by genotype. Both variants were associated with down-regulation of fibrogenic pathways. HSD17B13 perturbs plasma phosphatidylcholines and triglycerides. In silico modeling suggested p.Ala165Thr disrupts the stability and metal binding of MTARC1. Conclusion: Both HSD17B13 and MTARC1 variants are associated with less severe pediatric NAFLD. These results provide further evidence for shared genetic mechanisms between pediatric and adult NAFLD.

Depression, anxiety, substance misuse and self-harm in children and young people with rare chronic liver disease

The burden of mental illness in young people with chronic liver disease is not known. In this population cohort study in England, we identified 358 individuals (aged ≤25 years) diagnosed with autoimmune hepatitis or liver disease related to cystic fibrosis and 1541 propensity-score-matched controls. By the first year of follow-up, the cumulative burden of psychiatric events in participants with liver disease was high compared with controls: anxiety disorder (6.87 per 100 individuals [95% CI 4.00-9.73] v. 2.22 [95% CI 1.37-3.07]), depression (5.10 [95% CI 2.83-7.37] v. 0.86 [95% CI 0.53-1.19]), substance misuse (10.61 [95% CI 9.50-11.73] v. 1.23 [95% CI 0.71-1.75]) and self-harm (3.09 [95% CI 1.12-5.05] v. 0.20 [95% CI 0.07-0.33]). Participants with liver disease had a 2-fold increase (OR = 1.94, 95% CI 1.45-2.58), a 2.5-fold increase (OR = 2.59, 95% CI 1.91-3.50) and 4.4-fold increase (OR = 4.44; 95% CI 3.46-5.71) in the risk of anxiety, depression and substance misuse, respectively. These findings highlight the need for effective intervention in psychiatric disorders in young people with rare liver disease.

The Role of B Cells in Adult and Paediatric Liver Injury

B lymphocytes are multitasking cells that direct the immune response by producing pro- or anti-inflammatory cytokines, by presenting processed antigen for T cell activation and co-stimulation, and by turning into antibody-secreting cells. These functions are important to control infection in the liver but can also exacerbate tissue damage and fibrosis as part of persistent inflammation that can lead to end stage disease requiring a transplant. In transplantation, immunosuppression increases the incidence of lymphoma and often this is of B cell origin. In this review we bring together information on liver B cell biology from different liver diseases, including alcohol-related and metabolic fatty liver disease, autoimmune hepatitis, primary biliary and primary sclerosing cholangitis, viral hepatitis and, in infants, biliary atresia. We also discuss the impact of B cell depletion therapy in the liver setting. Taken together, our analysis shows that B cells are important in the pathogenesis of liver diseases and that further research is necessary to fully characterise the human liver B cell compartment.

Pharmacokinetics, Safety, and Efficacy of Glecaprevir/Pibrentasvir in Children With Chronic HCV: Part 2 of the DORA Study

BACKGROUND AND AIMS

Glecaprevir/pibrentasvir (GLE/PIB) has shown high efficacy and safety in chronic HCV-infected adults and adolescents; data in children were limited. DORA part 2 is a phase 2/3, nonrandomized, open-label study evaluating the pharmacokinetics, efficacy, and safety of a pediatric formulation of GLE and PIB in children ages 3 to < 12 years.

APPROACH AND RESULTS

Children with chronic HCV infection, genotype 1-6, with or without compensated cirrhosis, were divided into three cohorts by age-cohort 2 (9 to < 12 years), cohort 3 (6 to < 9 years), and cohort 4 (3 to < 6 years)-and given weight-based doses of GLE and PIB for 8, 12, or 16 weeks. Primary endpoints were sustained virologic response at posttreatment week 12 (SVR12) and steady-state exposure; secondary endpoints were rates of persistent viremia, relapse, and reinfection. Safety and laboratory abnormalities were assessed. Final pediatric dosages determined to be efficacious were 250 mg GLE + 100 mg PIB (in children weighing ≥ 30 to < 45 kg), 200 mg GLE + 80 mg PIB (≥ 20 to < 30 kg), and 150 mg GLE + 60 mg PIB (12 to < 20 kg). Of 80 participants enrolled and dosed, 96% (77/80) achieved SVR12. One participant, on the initial dose ratio, relapsed by posttreatment week 4; no participants had virologic failures on the final dose ratio of GLE 50 mg/PIB 20 mg. Two nonresponders prematurely discontinued the study. Most adverse events (AEs) were mild; no drug-related serious AEs occurred. Pharmacokinetic exposures were comparable to those of adults.

CONCLUSIONS

A pediatric formulation of GLE/PIB was highly efficacious and well tolerated in chronic HCV-infected children 3 to < 12 years old.

Juvenile haemochromatosis

Juvenile haemochromatosis is a severe inherited iron-loading disorder that can present in children and adolescents. Typical manifestations include heart failure, endocrine failure (including diabetes and hypogonadism), cirrhosis, and arthropathy. Compared with HFE haemochromatosis, juvenile haemochromatosis affects female and male individuals similarly, presents at a younger age, and causes multiple organ dysfunction; the principle of iron loading into tissues from the gut is shared by both forms, but the process is far more rapid in juvenile haemochromatosis. Juvenile haemochromatosis is initially recognised by extreme increases of serum ferritin and transferrin saturation, which is supported by an MRI showing iron deposition in the heart and liver. MRI software techniques allow quantification of iron in these organs, and can therefore be used to monitor progress. Juvenile haemochromatosis is autosomal recessive and is generally associated with mutations in HJV (type 2A) or HAMP (type 2B). Mutations in TFR2 cause an intermediate severity phenotype (type 3), but this phenotype can cross over into the juvenile haemochromatosis spectrum so it might need to be additionally considered during diagnosis. Treatment needs to be administered without delay, in the form of aggressive iron chelation, and a multidisciplinary approach is essential. Because iron is removed, organ function is restored, which could obviate the need for cardiac or liver transplantation. Substantial restoration of health can ensue, but patients require life-long monitoring. Family screening is an important component of the management of juvenile haemochromatosis. Genetic advances which underpin the haemochromatosis types also clarify the role of iron metabolism in health and disease, particularly the role of hepcidin in regulating iron homoeostasis. Therefore, juvenile haemochromatosis is an important condition to understand; it can present insidiously in children and adolescents, and awareness of the diagnosis is needed to inform early recognition and treatment.

Genotype correlates with the natural history of severe bile salt export pump deficiency

BACKGROUND & AIMS

Mutations in ABCB11 can cause deficiency of the bile salt export pump (BSEP), leading to cholestasis and end-stage liver disease. Owing to the rarity of the disease, the associations between genotype and natural history, or outcomes following surgical biliary diversion (SBD), remain elusive. We aimed to determine these associations by assembling the largest genetically defined cohort of patients with severe BSEP deficiency to date.

METHODS

This multicentre, retrospective cohort study included 264 patients with homozygous or compound heterozygous pathological ABCB11 mutations. Patients were categorized according to genotypic severity (BSEP1, BSEP2, BSEP3). The predicted residual BSEP transport function decreased with each category.

RESULTS

Genotype severity was strongly associated with native liver survival (NLS, BSEP1 median 20.4 years; BSEP2, 7.0 years; BSEP3, 3.5 years; p <0.001). At 15 years of age, the proportion of patients with hepatocellular carcinoma was 4% in BSEP1, 7% in BSEP2 and 34% in BSEP3 (p = 0.001). SBD was associated with significantly increased NLS (hazard ratio 0.50; 95% CI 0.27-0.94: p = 0.03) in BSEP1 and BSEP2. A serum bile acid concentration below 102 μmol/L or a decrease of at least 75%, each shortly after SBD, reliably predicted NLS of ≥15 years following SBD (each p <0.001).

CONCLUSIONS

The genotype of severe BSEP deficiency strongly predicts long-term NLS, the risk of developing hepatocellular carcinoma, and the chance that SBD will increase NLS. Serum bile acid parameters shortly after SBD can predict long-term NLS.

LAY SUMMARY

This study presents data from the largest genetically defined cohort of patients with severe bile salt export pump deficiency to date. The genotype of patients with severe bile salt export pump deficiency is associated with clinical outcomes and the success of therapeutic interventions. Therefore, genotypic data should be used to guide personalized clinical care throughout childhood and adulthood in patients with this disease.

Liver disease in the young adult: the challenges and rewards

Increasing numbers of children are surviving into adulthood with a diagnosis of liver disease or having undergone liver transplantation. This population presents some challenges for the adult hepatologist, and a formal transition service clearly improves outcomes for patients in this group. Evidence of ongoing neurological development in young people up to the age of 25 years exists, and understanding these physiological processes is important in overcoming some of the challenges that caring for this population presents. A well designed transition service is key to maximising potential for these patients, and should enable young people to take control of their illness and achieve their life goals.

Cardiac and Liver Disease in Children: Implications for Management Before and After Liver Transplantation

There is close interaction between the functions of the liver and heart affecting the presentation, diagnosis, and outcome of acute and chronic cardiac and liver disease. Conditions affecting both organ systems should be considered when proposing transplantation because the interaction between cardiac disease and liver disease has implications for diagnosis, management, selection for transplantation, and, ultimately, for longterm outcomes after liver transplantation (LT). The combination of cardiac and liver disease is well recognized in adults but is less appreciated in pediatric patients. The focus of this review is to describe conditions affecting both the liver and heart and how they affect selection and management of LT in the pediatric population.

The necessity of education and hepatitis B vaccination for young people: A study of high risk behaviour for blood borne viruses in the United Kingdom

Blood borne virus (BBV) infection in adults involved in high risk behaviour is well recognized. There are limited reported data on young people involved in high risk behaviour. A descriptive questionnaire was used to ascertain risk behaviour at the Young People's Substance Misuse Service (Birmingham). Data collection included risk behaviour and serological tests for hepatitis B, C and HIV. Sixty-five of one-hundred three (63%) young people participated; 37/65 male; age range 13.9-18.9 (median 17.4 years). Risk behaviour included 6 intravenous drug, 58 cannabis, and 61 had sexual partners, of whom 52 (85%) engaged in unprotected sex. Sixty-five participants were negative for BBV infection: 9 were HBV immune. HB vaccination was not available at the centre (for <18 year), and all refused referral to their general practitioner for vaccination due to fear of disclosure. The main risk for BBV acquisition was unprotected sex with multiple sexual partners and illicit drug use. Most were unaware of the risks related to high risk behaviour. Effective education programmes of relevant risk factors with HBV vaccination should be implemented during preadolescence. We recommend an integrated service via specialized centres, to work together to improve awareness and increase efforts to vaccinate adolescents at risk for HBV infection.

Epidemiology and natural history of hepatitis C virus infection among children and young people

BACKGROUND & AIMS

Chronic hepatitis C virus (HCV) infection is a global health burden. Although HCV infection rarely contributes to morbidity during childhood, most HCV-infected children develop chronic HCV with a lifetime risk of liver disease. Little is known about the development of long-term liver disease and the effect of treatment in patients infected with HCV in childhood.

METHOD

This study was a retrospective review of patients infected with HCV in childhood enrolled in HCV Research UK. A total of 1,049 patients were identified and included.

RESULTS

The main routes of infection were intravenous drug use (53%), blood product exposure (24%) and perinatal infection (11%). Liver disease developed in 32% of patients, a median of 33 years after infection, irrespective of the mode of infection. Therefore, patients with perinatal exposure developed cirrhosis at an earlier age than the rest of the risk groups. The incidence of hepatocellular carcinoma (HCC) was 5%, liver transplant 4% and death occurred in 3%. Overall, 663 patients were treated (55% with interferon/pegylated interferon and 40% with direct-acting antivirals). Sustained virological response (SVR) was achieved in 406 (75%). There was a higher mortality rate among patients without SVR vs. those with SVR (5% vs. 1%, p = 0.003). Treatment was more effective in patients without cirrhosis and disease progression was less frequent (13%) than in patients with cirrhosis at the time of therapy (28%) p < 0.001. Patients with cirrhosis were more likely to develop HCC, require liver transplantation, or die.

CONCLUSION

HCV infection in young people causes significant liver disease, which can now be prevented with antiviral therapy. Early treatment, especially before development of cirrhosis is essential. Detection of HCV should be aimed at relevant risk groups and antiviral therapy should be made available in childhood to prevent long-term liver disease and spread of HCV.

LAY SUMMARY

Chronic hepatitis C virus (HCV) infection is a global health problem, which can now be treated with potent direct-acting antiviral drugs. This study demonstrates that HCV infection in childhood causes serious liver disease in 32% of patients, a median of 33 years after infection, irrespective of age, mode and route of infection. Disease outcomes were better in patients treated before the development of advanced liver disease. Antiviral therapy should be made available in childhood to prevent long-term liver disease and the spread of HCV.

Hepatopulmonary Syndrome in Children: A 20-Year Review of Presenting Symptoms, Clinical Progression, and Transplant Outcome

Hepatopulmonary syndrome (HPS) in stable patients with cirrhosis can easily be overlooked. We report on the presenting symptoms, disease progression, and outcomes after liver transplantation (LT) in children with HPS. Twenty patients were diagnosed with HPS between 1996 and 2016. The etiologies were as follows: biliary atresia (n = 9); alpha-1-antitrypsin deficiency (n = 2); cryptogenic liver disease (n = 3); and others (n = 6). HPS presentations were as follows; dyspnea (n = 17) and pneumonia (n = 3). For diagnostic confirmation, the following techniques were used: technetium-99m-labeled macroaggregated albumin lung perfusion scan (n = 13) or contrast echocardiogram (n = 7). There were 16 patients listed for LT, with a median age at HPS diagnosis of 10 years and an average wait from listing to LT of 9 weeks. A marked rise in hemoglobin (Hb; median, 125-143.5 g/L) and modest decrease in oxygen saturation (SpO₂ ; median 91% to 88% room air) were evident over this time. Patients' need for assisted ventilation (1 day), pediatric intensive care unit (PICU) stay (3 days), and total hospital stay (20 days) were similar to our general LT recipients-the key difference in the postoperative period was the duration of supplementary O₂ requirement. Hb of ≥130 g/L on the day of LT correlated with a longer PICU stay (P value = 0.02), duration of supplementary O₂ (P value = 0.005), and the need for the latter beyond 7 days after LT (P value = 0.01). Fifteen patients had resolution of their HPS after LT. The 5-, 10-, and 20-year survival rates were unchanged at 87.5%. None had a recurrence of HPS. In conclusion, HPS is a life-threatening complication of cirrhosis which usually develops insidiously. This combined with the often-stable nature of the liver disease leads to delays in diagnosis and listing for LT. Progressive polycythemia extends the need for supplementary O₂ and PICU stay. We advocate screening for HPS with a combination of SpO₂ and Hb monitoring to facilitate earlier recognition, timely LT, and shortened recovery periods.

Acute infectious hepatitis in hospitalised children: a British Paediatric Surveillance Unit study

BACKGROUND

Hepatitis remains a key public health priority globally. Most childhood cases are caused by viruses, especially hepatitis A virus (HAV) and hepatitis B virus (HBV). This study aimed to estimate the burden of acute infectious hepatitis in hospitalised children and to describe their clinical characteristics and outcomes.

METHODS

Paediatricians in the UK and Ireland reported cases in children aged 1 month to 14 years diagnosed between January 2014 and January 2015 (inclusive) through the British Paediatric Surveillance Unit (BPSU) and completed a detailed questionnaire. Additional HAV and HBV cases in England and Wales were identified through a national electronic database, LabBase2. All confirmed cases were followed up at 6 months with a second questionnaire.

RESULTS

The BPSU survey identified 69 children (annual incidence, 0.52/100 000), including 27 HAV (39%), three HBV (4%), 16 other viruses (23%) and 23 with no aetiology identified (33%). LabBase2 identified an additional 10 HAV and 2 HBV cases in England. Of the 37 hospitalised HAV cases, 70% had travelled abroad, but only 8% had been vaccinated. Similarly, three of the five children with acute HBV had not been immunised, despite being a household contact of a known infectious individual. All patients with HAV recovered uneventfully. In contrast, three children with acute HBV developed liver failure and two required liver transplantation.

CONCLUSIONS

Acute infectious hepatitis is a rare cause of hospital admission. Most children recovered without complications, but those with acute HBV had severe presentations. At least three of the five HBV cases could have been prevented through appopriate vaccination of household contacts.

Parents in transition: Experiences of parents of young people with a liver transplant transferring to adult services

Predictors of successful transition from pediatric to adult services include ability to self-manage and engage with healthcare services. Parents have a key role in healthcare management throughout childhood and adolescence including encouraging development of self-management skills in their children. Transition to adult services can be challenging for parents and young people, yet parents' views regarding transition remain largely unexplored. Nine parents of pediatric liver transplant recipients (15.2-25.1 yr) participated in semistructured interviews. Interviews were analyzed using IPA. Analysis revealed three key themes: "emotional impact of transplantation," "protection vs. independence," and "ending relationships and changing roles." Parents expressed the dichotomous nature of the desire to promote independence in their child while still maintaining control and protection, and discussed how changing roles and relationships were difficult to navigate. Parents are important facilitators of young people's development of self-management skills for successful transfer to adult services. Parents should be supported to move from a "managerial" to a "supervisory" role during transition to help young people engage independently with the healthcare team. Findings support the development of interventions for parents to emphasize their role in transition and guide the transfer of self-management skills from parent to young person.

"Are these adult doctors gonna know me?" Experiences of transition for young people with a liver transplant

Excellent survival rates in paediatric LTx have resulted in increasing numbers of young people transferring from paediatric to adult care. Understanding the mechanisms of successful transition is imperative for ensuring good long-term outcomes and developing services for young people. Semi-structured interviews were conducted with 17 young people (10 females; age range: 15.2-25.1 years). Eight were within 1 year of transferring to adult services; nine had transferred. Interviews were analysed using IPA. Analysis revealed two major themes in both pre- and post-transfer groups: "relationships with healthcare professionals" and "continuity of care." Young people experienced difficulty ending relationships with paediatric clinicians and forming new relationships with adult clinicians. They expressed frustrations over a perceived lack of continuity of care after transfer and a fear of the unknown nature of adult services. The importance of a holistic approach to care was emphasized. Interventions are needed to support young people in transition, particularly in ending relationships in paediatric care and forming new relationships in adult care. Young people need help to develop strategies to cope with the different approaches in adult services. Interventions to provide clinicians with skills to communicate and engage with young people are imperative.

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.

Total Parenteral Nutrition-Induced Cholestasis: Prevention and Management

When cholestasis occurs in patients receiving total parenteral nutrition, it is the result of many pathogenic pathways converging on the hepatic acinus. The result may be a temporary rise in liver function tests. The resulting fibrosis, portal hypertension, and jaundice are hallmarks of type 3 intestinal-associated liver disease to which children are more susceptible than adults. The key to prevention is in identifying high-risk scenarios, meticulous monitoring, and personalized prescription of parenteral nutrition solutions combined with an active approach in reducing the impact of inflammatory events when they occur by prompt use of antibiotics and line locks.

'It's hard but you've just gotta get on with it'--The experiences of growing-up with a liver transplant

The successful evolution of paediatric liver transplantation means that increasing numbers of young people survive into adulthood. Non-adherence to medication regimens leading to liver dysfunction, graft loss and patient death are prevalent in this vulnerable group. Insight into young people's experiences of living with a liver transplant (LTx) is vital to improve outcomes and guide future work in this area. Through semi-structured interviews, this study explored the experiences of living with a LTx for 13 young people transplanted as children and adolescents. Interviews were analysed using interpretative phenomenological analysis, revealing that young people felt different from their peers as a result of their LTx. Young people's perceptions of their scar, experiences of illness symptoms and taking medications acted as triggers of differences. This led to an ongoing struggle to be normal when faced with typical activities for young people and to attempts to take back control. Findings support the implementation of routine psychosocial screening to identify additional support needs and the development of a peer mentoring programme to allow young people to gain social support, thus reducing feelings of being different. It is hoped that such initiatives will have positive consequences for quality of life, self-management and adherence to medications.

Treatment of chronic viral hepatitis C in children and adolescents: UK experience

AIM

To review the efficacy and tolerability of pegylated interferon-α and ribavirin for treatment of chronic hepatitis C (CHC) in children in the UK.

METHODS

Retrospective review of children treated for CHC in 3 UK paediatric specialist liver centres between 2005 and 2010. Data on viral response to treatment, demographic and clinical details were collected. Treatment outcome was assessed by the absence of detectable viral RNA in blood 24 weeks after treatment-sustained viral response (SVR).

RESULTS

75 children were included; 34 genotype 1; 39 genotypes 2 and 3; 2 genotype 4. Overall SVR was achieved in 54/71 (76%); 65% genotype 1; 89% genotypes 2 and 3; 100% genotype 4. Early response at 12 weeks was achieved in 53 and sustained in 47 (89%). Data on rapid response after 4 weeks of treatment were available in 25; 17/25 (68%) responded and 16 of these (94%) achieved SVR. IL28 T/T genotype was associated with higher SVR. There were no significant changes in weight and height z scores from baseline compared with 24 weeks post-treatment follow-up. No child discontinued treatment due to side effects, although 43 required dose modification. Treatment affected quality of life (QoL) in the initial 12 weeks of treatment, which improved by the end of treatment.

CONCLUSIONS

Children respond well to therapy for CHC. Treatment was tolerated with minimal impact on QoL and no significant effect on growth. Knowledge of viral and IL28 genotypes and early viral response is useful to plan treatment in children and provide appropriate counselling.

Vitamin D deficiency and insufficiency after pediatric liver transplantation

Vitamin D deficiency and insufficiency are increasingly recognized in the general population, including healthy children. There is also an increasing emphasis on the importance of vitamin D status following pediatric liver transplantation and specifically its relationship to metabolic bone disease and growth retardation. Vitamin D insufficiency has also been associated with multiple immunological and metabolic disorders in adults. To our knowledge, this has not been systematically evaluated in children undergoing liver transplantation to date. Between October 2004 and August 2008, serum 25-(OH)-vitamin D levels were measured in 199 children who had undergone liver transplantation at Birmingham Children's Hospital. Potential factors contributing to vitamin D levels were evaluated. Additionally, we evaluated a possible relationship between vitamin D levels and immunological phenomena and metabolic complications. Median 25-(OH)-vitamin D level was 19.5 ng/mL (range: 4.4-71.4 ng/mL). A total of 105 children (53%) had insufficient vitamin D levels and 28 children (14%) showed vitamin D deficiency. The only factors found to be associated with vitamin D deficiency were season of sample, ethnicity, and PTH levels. Vitamin D deficiency was more prevalent during the first year after transplantation. We did not find a significant relationship between vitamin D levels and graft function or any other immunological and metabolic complications. Vitamin D insufficiency and deficiency are common in children after liver transplantation, especially in winter and spring and in non-white patients. Initial post-transplant period and high PTH are significantly associated with vitamin D deficiency. Vitamin D status should be monitored following pediatric liver transplantation and vitamin D supplementation provided as required.

Differential control of sex differences in estrogen receptor α in the bed nucleus of the stria terminalis and anteroventral periventricular nucleus

The principal nucleus of the bed nucleus of the stria terminalis (BNSTp) and anteroventral periventricular nucleus of the hypothalamus (AVPV) are sexually dimorphic, hormone-sensitive forebrain regions. Here we report a profound sex difference in estrogen receptor-α (ERα) immunoreactivity (IR) in the BNSTp, with robust ERα IR in females and the near absence of labeling in males. This sex difference is due to the suppression of ERα IR by testicular hormones in adulthood: it was not present at birth and was not altered by neonatal treatment of females with estradiol; gonadectomy of adult males increased ERα IR to that of females, whereas gonadectomy of adult females had no effect. Treating gonadally intact males with an aromatase inhibitor partially feminized ERα IR in the BNSTp, suggesting that testicular suppression required aromatization. By contrast, in AVPV we found a modest sex difference in ERα IR that was relatively insensitive to steroid manipulations in adulthood. ERα IR in AVPV was, however, masculinized in females treated with estradiol at birth, suggesting that the sex difference is due to organizational effects of estrogens. The difference in ERα IR in the BNSTp of males and females appears to be at least in part due to greater expression of mRNA of the ERα gene (Esr1) in females. The sex difference in message is smaller than the difference in immunoreactivity, however, suggesting that posttranscriptional mechanisms also contribute to the pronounced suppression of ERα IR and presumably to functions mediated by ERα in the male BNSTp.

A combination of mutations in AKR1D1 and SKIV2L in a family with severe infantile liver disease

Infantile cholestatic diseases can be caused by mutations in a number of genes involved in different hepatocyte molecular pathways. Whilst some of the essential pathways have a well understood function, such as bile biosynthesis and transport, the role of the others is not known. Here we report the findings of a clinical, biochemical and molecular study of a family with three patients affected with a severe infantile cholestatic disease. A novel homozygous frameshift germline mutation (c.587delG) in the AKR1D1 gene; which encodes the enzyme Δ ⁴-3-oxosteroid 5β–reductase that is required for synthesis of primary bile acids and is crucial for establishment of normal bile flow, was found in all 3 patients. Although the initial bile acid analysis was inconclusive, subsequent testing confirmed the diagnosis of a bile acid biogenesis disorder. An additional novel homozygous frameshift mutation (c.3391delC) was detected in SKIV2L in one of the patients. SKIV2L encodes a homologue of a yeast ski2 protein proposed to be involved in RNA processing and mutations in SKIV2L were recently described in patients with Tricohepatoenteric syndrome (THES). A combination of autozygosity mapping and whole-exome-sequencing allowed the identification of causal mutations in this family with a complex liver phenotype. Although the initial 2 affected cousins died in the first year of life, accurate diagnosis and management of the youngest patient led to successful treatment of the liver disease and disease-free survival.

Alagille syndrome and other hereditary causes of cholestasis

Neonatal conjugated jaundice is a common presentation of hereditary liver diseases, which, although rare, are important to recognize early. Developments in molecular genetic techniques have enabled the identification of causative genes, which has improved diagnostic accuracy for patients and has led to a greater understanding of the molecular pathways involved in liver biology and pathogenesis of liver diseases. This review provides an update of the current understanding of clinical and molecular features of the inherited liver diseases that cause neonatal conjugated jaundice.

Durability of sustained response shown in paediatric patients with chronic hepatitis C who were treated with interferon alfa-2b plus ribavirin

Long-term studies in adults indicate that sustained virologic response (SVR) after combination treatment for chronic hepatitis C (CHC) predicts long-term clearance. Although peginterferon plus ribavirin is now standard care for children with CHC, long-term follow-up studies are not yet available. This study evaluated durability of virologic response over 5 years in children previously treated with interferon alfa-2b plus ribavirin (IFN/R). Ninety-seven of 147 children with CHC, who were treated with IFN/R and completed the 6-month follow-up in two previous clinical trials, participated in this long-term follow-up study. All were assessed annually for up to 5 years; patients with SVR were assessed for durability of virologic response. Children with SVR (n = 56) and those with detectable hepatitis C virus (HCV) RNA 24-week post-treatment (n = 41) were followed for a median of 284 weeks. Overall, 70% (68/97) of patients completed the 5-year follow-up. One patient with genotype 1a CHC had SVR and relapsed at year 1 of follow-up with the same genotype. Kaplan-Meier estimate for sustained response at 5 years was 98% (95% CI: 95%, 100%). Six patients with low-positive HCV RNA levels (n = 4) or missing HCV RNA at the 24-week follow-up visit (n = 2) in the initial treatment studies had virologic response during this long-term follow-up study. Linear growth rate was impaired during treatment with rapid increases in the immediate 6 months post-treatment. Mean height percentile at the end of the 5-year follow-up was slightly less than the mean pretreatment height percentile. Five patients experienced serious adverse events; none related to study drug exposure. SVR after IFN/R predicts long-term clearance of HCV in paediatric patients; growth normalized in the majority of children during the long-term follow-up. Similar long-term results could be expected after peginterferon alfa-2b plus ribavirin treatment.

ABO-incompatible pediatric liver transplantation in very small recipients: Birmingham's experience

Liver transplantation (LT) for very small recipients is challenging but in experienced centres, good results can be achieved. Despite the risk of antibody-mediated acute rejection, some studies have demonstrated the safety of ABO incompatible liver transplantation (ILT) in children and particularly in infants. The aim of our study was to describe the outcome of liver transplantation in infants <5 kg and the safety of using ILT in this group. All LT performed between 1991 and 2010 in children <5 kg were reviewed. Twenty-nine patients were included, five of whom had an ILT. Acute liver failure was encountered in 20 cases. The recipient age and weight at transplantation were respectively 63 days (range: 14-268 days) and 4 kg (range: 2.4-5 kg). The graft-to-recipient ratio was 6.1% (range 2.3-9%). An aortic conduit and delayed abdominal closure were used respectively in 76% and 81% of the procedures. The ABO compatible liver transplantation (CLT) and ILT groups were similar regarding recipient's demographics, graft types or technical transplantation data. The one- and five-yr patient and graft survival were respectively 62%, 62% and 62%, 57.9% with a median follow-up of 95 months. Vascular complications occurred in six cases (21.4%) and biliary complications were encountered in five patients (17%). Acute and chronic rejection developed respectively in 37% and 26% of the recipients. The five patients undergoing ILT are all alive without graft lost after a median follow-up of 34 months (range 7-55 months). When compared with the CLT group, no significant differences were found regarding patient or graft survival, vascular or biliary complications and rejection rates. In our experience, ILT in small infants has short and long term outcomes comparable to ABO-compatible grafts and excellent results can be achieved with a standard immunosuppressive protocol. To avoid mortality on the waiting list for neonatal recipients, ABO-incompatible liver grafts can be used safely.

Chronic hepatitis C in children--review of natural history at a National Centre

The natural history of hepatitis C virus (HCV) infection in adults has been established, but less is known about outcome in children. We conducted a retrospective review of patients referred to Birmingham Children's Hospital Liver Unit, from 1991 till 2008, with the diagnosis of HCV was undertaken. Only children with documented positive HCV RNA and a minimum duration of follow-up of 6 months were included. One hundred and thirty-three children were identified. The route of transmission was transfusion acquired in 47%, vertically acquired in 49% and transplantation in 2%. Since 2000, most children were infected vertically. The overall rate of spontaneous viral clearance was 17.5% with higher clearance (27%) in the transfusion group compared to the vertically acquired group (9%). Seventy-six had a liver biopsy at diagnosis. There was no evidence of fibrosis in 46%, mild fibrosis in 50% and moderate to severe fibrosis in 4%. None had cirrhosis. There was a statistically significant relationship between fibrosis score and older age at the time of biopsy (P = 0.02) and longer duration of infection (P = 0.05). Eighty children received treatment for HCV. Sustained viral response (SVR) was influenced by viral genotypes, with significantly increased response rates in genotypes (G) 2 and 3 compared to G 1 and 4. Vertical infection is now the major route of HCV infection in children in the UK. Histological changes were mild at diagnosis, but the severity of fibrosis progressed with age. Consideration should be given to improve detection and diagnosis to refer children to specialist centres for management and antiviral therapy before developing fibrosis.

Biliary atresia in England and Wales: results of centralization and new benchmark

INTRODUCTION

Biliary atresia (BA) is a rare, potentially life-threatening condition of the newborn presenting with conjugated jaundice. Typically, it is treated by an initial attempt to restore bile flow (the Kasai portoenterostomy [KP]) as soon as possible after diagnosis and, if this fails, liver transplantation. Since 1999, the treatment of BA has been centralized to 3 centers in England and Wales able to offer both treatment options. The aim of this study was to review the outcome of this policy change and provide a national benchmark.

METHODS

The management of all infants born within England and Wales during the period January 1999 to December 2009 was assessed using 3 key performance indicators such as median time to KP, percentage clearance of jaundice (≤20 mol/L) post-KP, and 5- and 10-year native liver and true survival estimates. Data are quoted as median (range), and P < .05 was considered significant.

RESULTS

A total of 443 infants had confirmed BA; and of these, most were isolated BA (n = 359), with 84 having other significant anomalies (but predominantly BA splenic malformation syndrome). Four infants died before any biliary intervention. Kasai portoenterostomy was performed in 424 infants (median age, 54 [range 7-209] days), and a primary liver transplant was performed in 15. Clearance of jaundice post-KP was achieved in 232 (55%). There were 41 deaths, including 4 (10%) without any intervention, 24 (58%) post-KP usually because of end-stage liver disease and mostly on a transplant waiting list, and 13 (32%) post-LT usually because of multiorgan failure. Overall, the 5- and 10-year native liver survival estimates were 46% (95% confidence interval [CI], 41-51) and 40% (95% CI, 34-46), respectively. The 5- and 10-year true patient survival estimates were 90% (95% CI, 88-93) and 89% (95% CI, 86-93), respectively. Outcome was worse for those with other anomalies (lower clearance of jaundice post-KP [43% vs 57%; odds ratio, 1.7; 95% CI, 1.04-2.8]; P = .02) and an increased mortality overall (eg, at 5 years, 72 [95% CI, 64-83] vs 94 [95% CI, 91-96]; χ(2) = 33; P < .0001).

CONCLUSIONS

National outcome measures in BA appear better than those from previously published series from comparable countries and may be attributed to centralization of surgical and medical resources.

Preventing parenteral nutrition liver disease

Parenteral nutrition liver disease (PNLD) develops in 40-60% of infants who require long-term PN for intestinal failure. The clinical spectrum includes hepatic steatosis, cholestasis, cholelithiasis, and hepatic fibrosis. Progression to biliary cirrhosis and the development of portal hypertension and liver failure occurs in a minority who require combined liver and intestinal transplantation. The pathogenesis is multifactorial and is related to prematurity, low birth weight, duration of PN, short bowel syndrome requiring multiple laparotomies and recurrent sepsis. Other important mechanisms include lack of enteral feeding which leads to reduced gut hormone secretion, reduction of bile flow and biliary stasis which leads to the development of cholestasis, biliary sludge and gallstones, which exacerbate hepatic dysfunction, especially in premature neonates with immature hepatic function. The use of lipid emulsions, particularly soy bean emulsions have been associated with hepatic cholestasis in children, although there are little data now to support toxicity from other PN components. Management strategies for the prevention of parenteral nutrition liver disease include consideration of early enteral feeding, a multidisciplinary approach to the management of parenteral nutrition with a specialized nutritional care team and aseptic catheter techniques to reduce sepsis. The use of specialized lipid emulsions such as fish oil emulsions and or SMOF (Soy bean/Medium Chain Triglyceride/Olive Oil/Fish oil) improves established cholestasis and may prevent the onset. Oral administration of ursodeoxycholic acid may improve bile flow and reduce gall bladder stasis, although there is little data to suggest that prophylactic use prevents the onset of PNLD. Survival following either isolated small bowel or combined liver and small bowel transplantation is approximately 50% at 5 years making this an acceptable therapeutic option in children with irreversible liver and intestinal failure.

Primary hepatic sarcomas in children--a single-center experience over 19 years

BACKGROUND/PURPOSE

Primary hepatic sarcomas are rare and account for about 13% of primary hepatic neoplasms. There are few reported series of pediatric hepatic sarcomas, and the aim was to review our experience.

METHODS

A retrospective analysis of cases managed from 1988 to 2007 by the pediatric liver unit in Birmingham, UK, was conducted.

RESULTS

Nineteen children were identified. These presented with sudden abdominal pain (n = 6), obstructive jaundice (n = 3), incidental mass (n = 3), and chronic pain/distension (n = 3). Vascular involvement was identified in 3, and 6 had pulmonary metastases. Three patients had primary resection, and 3 only a biopsy. Thirteen had a biopsy followed by chemotherapy and resection. Surgery included extended hepatectomy (n = 11), hepatectomy (n = 3), and nonanatomical resections (n = 2). There was 1 major intraoperative complication. Median inpatient stay was 7 days. One biliary leak developed 4 weeks postoperatively. Five of the 16 patients who underwent resection of the primary tumor died. Eleven were alive at a median follow-up of 3 years.

CONCLUSION

This is a challenging group of patients. Local control remains pivotal to successful treatment. Good results can be achieved in a specialist center with multidisciplinary approach.

The challenges and opportunities for transitional care research

The provision of healthcare for young people with solid organ transplants as they move into adult-centered services has received increasing attention over recent years particularly as non-adherence and graft loss increase after transfer. Despite medical advances and that transitional care is now well established on national and international health agendas, progress in the research arena has unfortunately been slow. The aims of this paper are to consider why this is and discuss the particular challenges facing clinical researchers working within the area.

Surgical complications after intestinal transplantation in infants and children--UK experience

Surgical complications have a significant impact on morbidity and mortality following intestinal transplantation (ITx). Birmingham Children's Hospital commenced intestinal transplantation in 1993 and the following surgical strategies evolved: (a) pretransplant abdominal tissue expanders, 1998; (b) combined en-bloc reduced liver and intestinal transplantation (CRLITx), 1998; (c) staged abdominal closure, 2001; (d) preservation of graft duodenal artery, 2005.

AIM

An internal audit was performed to document the surgical complications after ITx and to evaluate strategies in the management and prevention of complications.

METHODS

A retrospective analysis of the medical records from January 1993 to June 2007 was conducted to identify surgical complications, evaluate management strategies, and report outcome following ITx.

RESULTS

Forty-six children underwent 49 ITx (9 isolated intestinal, 39 combined liver and intestinal [CLITx], and 1 multivisceral transplant). Twenty three children had CRLITx since 1998, although there were none before 1997. The median donor: recipient weight ratio in CLITx was 2.2:1 (range, 0.67:1-6.70:1). Twenty-six children experienced 29 (59%) surgical complications: portacaval shunt thrombosis (n = 2, none alive); graft duodenal stump leakage (n = 3, 2 alive); spontaneous bowel perforation(n = 6, 2 alive); sub-acute bowel obstruction (n = 6, all alive); abdominal compartment syndrome ([ACS], n = 4, 2 alive); pancreatic leak (n = 3, 2 alive); biliary complications (n = 22, 17 alive ) failed staged abdominal closure with wound sepsis requiring skin grafting into the bowel (n = 1, alive), wound dehiscence (n = 1, alive), anastomotic leak (n = 1, alive) and intra-abdominal bleeding (n = 1,alive), primary nonfunction (n = 1, 1 died). Following the complications of ACS in children with primary abdominal closure and graft duodenal stump leaks in 2004, we modified our strategies in 2005 to include staged abdominal closure with recipient to donor weight mismatch, and preservation of the gastroduodenal artery during donor organ procurement in addition to pre transplant abdominal tissue expansion. Fifteen children with recipient and donor weight mismatch subsequently required staged closure of the abdomen and none of them developed ACS. Twelve children had gastroduodenal artery preserved and none developed graft duodenal stump leaks. Twenty-four of the 46 (52%) are alive 6 months to 10 years post transplant.

CONCLUSION

Evolving strategies may avoid or reduce surgical complications commonly seen after intestinal transplantation and thus contribute to an improved outcome.

Liver transplantation in children using non-heart-beating donors (NHBD)

Selected livers from controlled NHBD are accepted for OLT in adults. Recent evidence has shown good medium-term outcome. The purpose of this study was to report our experience of pediatric OLT with whole and partial grafts from NHBD, analyzing complications and outcome. Retrospective review of all the recipients who underwent primary OLT between December 2005 and December 2008, using livers from NHBD. Four children (one male child) mean age was 9.5 yr (0.2-17), mean weight was 26 kg (range 2.6-48), underwent OLT using NHBD. Mean donor age was 14.2 yr, and mean WIT (systolic BP<50 mmHg to cold perfusion) 12.2 min (range 10-15). Two children received reduced grafts and two full grafts. Mean cold ischemia time was 7.18 h (range 6-8). Liver function tests one wk and nine months post-OLT confirmed a good graft function. One child was treated for two episodes of acute rejection. Post-transplant complications included two cases of mild ischemic cholangiopathy treated conservatively. Graft and patient survival was 100% with a mean follow-up of 19 months (range 8.1-43.4). Short- to medium-term follow-up suggests that liver grafts from young NHBD with short warm and cold ischemia times can be safely utilized in pediatric transplantation.

Mutations in TTC37 cause trichohepatoenteric syndrome (phenotypic diarrhea of infancy)

BACKGROUND & AIMS

Trichohepatoenteric syndrome (THES) is an autosomal-recessive disorder characterized by life-threatening diarrhea in infancy, immunodeficiency, liver disease, trichorrhexis nodosa, facial dysmorphism, hypopigmentation, and cardiac defects. We attempted to characterize the phenotype and elucidate the molecular basis of THES.

METHODS

Twelve patients with classic THES from 11 families had detailed phenotyping. Autozygosity mapping was undertaken in 8 patients from consanguineous families using 250,000 single nucleotide polymorphism arrays and linked regions evaluated using microsatellite markers. Linkage was confirmed to one region from which candidate genes were analyzed. The effect of mutations on protein production and/or localization in hepatocytes and intestinal epithelial cells from affected patients was characterized by immunohistochemistry.

RESULTS

Previously unrecognized platelet abnormalities (reduced platelet alpha-granules, unusual stimulated alpha granule content release, abnormal lipid inclusions, abnormal platelet canalicular system, and reduced number of microtubules) were identified. The THES locus was mapped to 5q14.3-5q21.2. Sequencing of candidate genes showed mutations in TTC37, which encodes the uncharacterized tetratricopeptide repeat protein, thespin. Bioinformatic analysis suggested thespin to be involved in protein-protein interactions or chaperone. Preliminary studies of enterocyte brush-border ion transporter proteins (sodium hydrogen exchanger 2, sodium hydrogen exchanger 3, aquaporin 7, sodium iodide symporter, and hydrogen potassium adenosine triphosphatase [ATPase]) showed reduced expression or mislocalization in all THES patients with different profiles for each. In contrast the basolateral localization of Na/K ATPase was not altered.

CONCLUSIONS

THES is caused by mutations in TTC37. TTC37 mutations have a multisystem effect, which may be owing to abnormal stability and/or intracellular localization of TTC37 target proteins.

Mutations in VIPAR cause an arthrogryposis, renal dysfunction and cholestasis syndrome phenotype with defects in epithelial polarization

Arthrogryposis, renal dysfunction and cholestasis syndrome (ARC) is a multisystem disorder associated with abnormalities in polarized liver and kidney cells. Mutations in VPS33B account for most cases of ARC. We identified mutations in VIPAR (also called C14ORF133) in individuals with ARC without VPS33B defects. We show that VIPAR forms a functional complex with VPS33B that interacts with RAB11A. Knockdown of vipar in zebrafish resulted in biliary excretion and E-cadherin defects similar to those in individuals with ARC. Vipar- and Vps33b-deficient mouse inner medullary collecting duct (mIMDC-3) cells expressed membrane proteins abnormally and had structural and functional tight junction defects. Abnormal Ceacam5 expression was due to mis-sorting toward lysosomal degradation, but reduced E-cadherin levels were associated with transcriptional downregulation. The VPS33B-VIPAR complex thus has diverse functions in the pathways regulating apical-basolateral polarity in the liver and kidney.

Biliary atresia

Biliary atresia is a rare disease of infancy, which has changed within 30 years from being fatal to being a disorder for which effective palliative surgery or curative liver transplantation, or both, are available. Good outcomes for infants depend on early referral and timely Kasai portoenterostomy, and thus a high index of suspicion is needed for investigation of infants with persistent jaundice. In centres with much experience of treating this disorder, up to 60% of children will achieve biliary drainage after Kasai portoenterostomy and will have serum bilirubin within the normal range within 6 months. 80% of children who attain satisfactory biliary drainage will reach adolescence with a good quality of life without undergoing liver transplantation. Although much is known about management of biliary atresia, many aspects are poorly understood, including its pathogenesis. Several hypotheses exist, implicating genetic predisposition and dysregulation of immunity, but the cause is probably multifactorial, with obliterative extrahepatic cholangiopathy as the common endpoint. Researchers are focused on identification of relevant genetic and immune factors and understanding serum and hepatic factors that drive liver fibrosis after Kasai portoenterostomy. These factors might become therapeutic targets to halt the inevitable development of cirrhosis and need for liver transplantation.

Calcineurin inhibitor minimization in pediatric liver allograft recipients

The use of CNI in pediatric LTx has dramatically improved the outcome for children with end-stage liver disease by significantly reducing the rate of acute and chronic rejection. Long-term concerns about CNI-induced nephrotoxicity and other adverse effects remain an issue, particularly as the emphasis moves from short-term survival to long-term quality of life. This review summarizes lessons learnt from pediatric and adult solid organ transplantation in minimizing CNI use in immunosuppression protocols in children following LTx. There are three models for CNI minimization: dose reduction, withdrawal or avoidance, supplemented by the use of IL-2 receptor blocking antibodies in the peri-transplant period, and early transition to alternate drugs such as MMF or SRL. Prospective studies evaluating reduction or withdrawal protocols in adult and pediatric LTx indicate that rejection rates are comparable with traditional CNI-based immunosuppression and that two and five yr patient and graft survival are similar, with recovery in renal function. There are few studies evaluating complete avoidance of CNI, apart from that in renal transplantation, although the benefits of long-term reduction in cardiovascular, metabolic, and possibly neoplastic side effects may justify this approach. It is not clear yet how CNI minimization will affect the development of tolerance but experimental and preliminary clinical studies indicate that CNI and steroid avoidance or minimization in the peri-operative period may favor the development of long-term graft tolerance. In summary, CNI minimization may be safe and effective in the short term but large-scale pediatric randomized studies are required to evaluate the long-term efficacy of these regimes in the development of chronic rejection, PTLD, and graft tolerance.