Single-cell multiomics reveals the interplay of clonal evolution and cellular plasticity in hepatoblastoma.

Hepatoblastomas (HB) display heterogeneous cellular phenotypes that influence the clinical outcome, but the underlying mechanisms are poorly understood. Here, we use a single-cell multiomic strategy to unravel the molecular determinants of this plasticity. We identify a continuum of HB cell states between hepatocytic (scH), liver progenitor (scLP) and mesenchymal (scM) differentiation poles, with an intermediate scH/LP population bordering scLP and scH areas in spatial transcriptomics. Chromatin accessibility landscapes reveal the gene regulatory networks of each differentiation pole, and the sequence of transcription factor activations underlying cell state transitions. Single-cell mapping of somatic alterations reveals the clonal architecture of each tumor, showing that each genetic subclone displays its own range of cellular plasticity across differentiation states. The most scLP subclones, overexpressing stem cell and DNA repair genes, proliferate faster after neo-adjuvant chemotherapy. These results highlight how the interplay of clonal evolution and epigenetic plasticity shapes the potential of HB subclones to respond to chemotherapy.

Disrupted BMP-9 Signaling Impairs Pulmonary Vascular Integrity in Hepatopulmonary Syndrome.

RATIONALE: Hepatopulmonary syndrome (HPS) is a severe complication of liver diseases characterized by abnormal dilatation of pulmonary vessels, resulting in impaired oxygenation. Recent research highlights the pivotal role of liver-produced bone morphogenetic protein (BMP)-9 in maintaining pulmonary vascular integrity. OBJECTIVES: This study aimed to investigate the involvement of BMP-9 in human and experimental HPS. METHODS: Circulating BMP-9 levels were measured in 63 healthy controls and 203 cirrhotic patients, with or without HPS. Two animal models of portal hypertension were employed: common bile duct ligation (CBDL) with cirrhosis and long-term partial portal vein ligation (PPVL) without cirrhosis. Additionally, the therapeutic effect of low-dose BMP activator FK506 was investigated, and the pulmonary vascular phenotype of BMP-9 knockout rats was analyzed. MEASUREMENTS AND MAIN RESULTS: Patients with HPS related to compensated cirrhosis demonstrated lower levels of circulating BMP-9 compared to patients without HPS. Severe cirrhosis patients exhibited consistently low levels of BMP-9. In animal models, HPS characteristics, including intrapulmonary vascular dilations (IPVDs) and alveolo-arterial gradient enlargement, were observed. HPS development in both rat models correlated with reduced intrahepatic BMP-9 expression, decreased circulating BMP-9 level and activity, and impaired pulmonary BMP-9 endothelial pathway. Daily treatment with FK506 for 2-weeks restored BMP pathway in the lungs, alleviating IPVDs, and improving gas exchange impairment. Furthermore, BMP-9 knockout rats displayed a pulmonary HPS phenotype, supporting its role in disease progression. CONCLUSION: The study findings suggest that portal hypertension-induced loss of BMP-9 signaling contributes to HPS development.

Long-term outcome of combined radiologic and surgical strategy for the management of biliary complications after pediatric liver transplantation.

OBJECTIVES: We aimed to analyze the risk factors for management failure of BC after pediatric liver transplantation (pLT) by retrospectively analyzing primary pLT performed between 1997 and 2018 (n = 620 patients). RESULTS: In all, 117/620 patients (19%) developed BC. The median (range) follow-up was 9 (1.4-21) years. Patient survival at 1, 5 and 10 years was 88.9%, 85.7%, 84.4% and liver graft survival was 82.4%, 77.4%, and 74.3% respectively. Graft not patient survival was impaired by BC (p = 0.01). Multivariate analysis identified the number of dilatation courses > 2 (p = 0.008), prolonged cold ischemia time (p = 0.004), anastomosed multiple biliary ducts (p = 0.019) and hepatic artery thrombosis (p = 0.01) as factors associated with impaired graft survival. The number of dilatation courses > 2 (p < 0.001) and intrahepatic vs anastomotic stricture (p = 0.014) were associated with management failure. Thus, repeated (> 2) radiologic dilatation courses are associated with impaired graft survival and management failure. Overall, graft but not patient survival was impaired by BC.

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.

∆4-3-oxo-5ß-reductase deficiency: favorable outcome in 16 patients treated with cholic acid.

BACKGROUND: Oral cholic acid therapy is an effective therapy in children with primary bile acid synthesis deficiencies. Most reported patients with this treatment have 3ß-hydroxy-Δ5-C27-steroid oxidoreductase deficiency. The aim of the study was the evaluation of cholic acid therapy in a cohort of patients with the rarer Δ4-3-oxosteroid 5ß-reductase (Δ4-3-oxo-R) deficiency. METHODS: Sixteen patients with Δ4-3-oxo-R deficiency confirmed by AKR1D1 gene sequencing who received oral cholic acid were retrospectively analyzed. RESULTS: First symptoms were reported early in life (median 2 months of age), with 14 and 3 patients having cholestatic jaundice and severe bleeding respectively. Fifteen patients received ursodeoxycholic acid before diagnosis, with partial improvement in 8 patients. Four patients had liver failure at the time of cholic acid initiation. All 16 patients received cholic acid from a median age of 8.1 months (range 3.1-159) and serum liver tests normalized in all within 6-12 months of treatment. After a median cholic acid therapy of 4.5 years (range 1.1-24), all patients were alive with their native liver. Median daily cholic acid dose at last follow-up was 8.3 mg/kg of body weight. All patients, but one, had normal physical examination and all had normal serum liver tests. Fibrosis, evaluated using liver biopsy (n = 4) or liver elastography (n = 9), had stabilized or improved. Cholic acid therapy enabled a 12-fold decrease of 3-oxo-∆4 derivatives in urine. Patients had normal growth and quality of life. The treatment was well tolerated without serious adverse events and signs of hepatotoxicity. CONCLUSIONS: Oral cholic acid therapy is a safe and effective treatment for patients with Δ4-3-oxo-R deficiency.

Liver disease in germline mutations of telomere-related genes: Prevalence, clinical, radiological, pathological features, outcome, and risk factors.

BACKGROUND AND AIM: Germline mutations of telomere-related genes (TRG) induce multiorgan dysfunction, and liver-specific manifestations have not been clearly outlined. We aimed to describe TRG mutations-associated liver diseases. APPROACH AND RESULTS: Retrospective multicenter analysis of liver disease (transaminases > 30 IU/L and/or abnormal liver imaging) in patients with TRG mutations. Main measurements were characteristics, outcomes, and risk factors of liver disease in a TRG mutations cohort. The prevalence of liver disease was compared to a community-based control group (n = 1190) stratified for age and matched 1:3 for known risk factors of liver disease. Among 132 patients with TRG mutations, 95 (72%) had liver disease, with associated lung, blood, skin, rheumatological, and ophthalmological TRG diseases in 82%, 77%, 55%, 39%, and 30% of cases, respectively. Liver biopsy was performed in 52/95 patients, identifying porto-sinusoidal vascular disease in 48% and advanced fibrosis/cirrhosis in 15%. After a follow-up of 21 months (12-54), ascites, hepato-pulmonary syndrome, variceal bleeding, and HCC occurred in 14%, 13%, 13%, and 2% of cases, respectively. Five-year liver transplantation-free survival was 69%. A FIB-4 score ≥ 3·25 and ≥1 risk factor for cirrhosis were associated with poor liver transplantation-free survival. Liver disease was more frequent in patients with TRG mutations than in the paired control group [80/396, (20%)], OR 12.9 (CI 95%: 7.8-21.3, p < 0.001). CONCLUSIONS: TRG mutations significantly increase the risk of developing liver disease. Although symptoms may be mild, they may be associated with severe disease. Porto-sinusoidal vascular disease and cirrhosis were the most frequent lesions, suggesting that the mechanism of action is multifactorial.

Outcomes of 38 patients with PFIC3: Impact of genotype and of response to ursodeoxycholic acid therapy.

Background & Aims: Progressive familial intrahepatic cholestasis type 3 (PFIC3) is a rare liver disease caused by biallelic variations in ABCB4. Data reporting on the impact of genotype and of response to ursodeoxycholic acid (UDCA) therapy on long-term outcomes are scarce. Methods: We retrospectively describe a cohort of 38 patients with PFIC3 with a median age at last follow-up of 19.5 years (range 3.8-53.8). Results: Twenty patients presented with symptoms before 1 year of age. Thirty-one patients received ursodeoxycholic acid (UDCA) therapy resulting in serum liver test improvement in 20. Twenty-seven patients had cirrhosis at a median age of 8.1 years of whom 18 received a liver transplant at a median age of 8.5 years. Patients carrying at least one missense variation were more likely to present with positive (normal or decreased) canalicular MDR3 expression in the native liver and had prolonged native liver survival (NLS; median 12.4 years [range 3.8-53.8]). In contrast, in patients with severe genotypes (no missense variation), there was no detectable canalicular MDR3 expression, symptom onset and cirrhosis occurred earlier, and all underwent liver transplantation (at a median age of 6.7 years [range 2.3-10.3]). The latter group was refractory to UDCA treatment, whereas 87% of patients with at least one missense variation displayed an improvement in liver biochemistry in response to UDCA. Biliary phospholipid levels over 6.9% of total biliary lipid levels predicted response to UDCA. Response to UDCA predicted NLS. Conclusions: Patients carrying at least one missense variation, with positive canalicular expression of MDR3 and a biliary phospholipid level over 6.9% of total biliary lipid levels were more likely to respond to UDCA and to exhibit prolonged NLS. Impact and implications: In this study, data show that genotype and response to ursodeoxycholic acid therapy predicted native liver survival in patients with PFIC3 (progressive familial intrahepatic cholestasis type 3). Patients carrying at least one missense variation, with positive (decreased or normal) immuno-staining for canalicular MDR3, and a biliary phospholipid level over 6.9% of total biliary lipids were more likely to respond to ursodeoxycholic acid therapy and to exhibit prolonged native liver survival.

Predictors of 6-year event-free survival in Alagille syndrome patients treated with maralixibat, an ileal bile acid transporter inhibitor.

BACKGROUND AND AIMS: Refractory pruritus and other complications of cholestasis are indications for liver transplantation (LT) in patients with Alagille syndrome (ALGS). We evaluated predictors of event-free survival and transplant-free survival in patients with ALGS treated with maralixibat (MRX), an ileal bile acid transporter inhibitor. APPROACH AND RESULTS: We assessed patients with ALGS from 3 clinical trials of MRX with up to 6 years of follow-up. Event-free survival was defined as the absence of LT, surgical biliary diversion, hepatic decompensation, or death; transplant-free survival was the absence of LT or death. Forty-three potential predictors were evaluated, including age, pruritus (ItchRO[Obs] 0-4 scale), biochemistries, platelets, and serum bile acids. Harrell's concordance statistic assessed goodness-of-fit, and then, Cox proportional hazard models confirmed the statistical significance of the predictors identified. A further analysis was performed to identify cutoffs using a grid search. Seventy-six individuals met the criteria of receiving MRX for ≥48 weeks with laboratory values available at week 48 (W48). The median duration of MRX was 4.7 years (IQR: 1.6-5.8); 16 had events (10 LT, 3 decompensation, 2 death, and 1 surgical biliary diversion). The 6-year event-free survival improved with a clinically meaningful >1-point ItchRO(Obs) reduction from baseline to W48 (88% vs. 57%; p = 0.005), W48 bilirubin < 6.5 mg/dL (90% vs. 43%; p < 0.0001), and W48 serum bile acid < 200 µmol/L (85% vs. 49%; p = 0.001). These parameters were also predictive of 6-year transplant-free survival. CONCLUSIONS: Improvement in pruritus by 48 weeks, and lower W48 bilirubin and serum bile acid levels were associated with fewer events. These data may help identify potential markers of disease progression for ALGS patients treated with MRX.

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.

Genotype-phenotype relationships of truncating mutations, p.E297G and p.D482G in bile salt export pump deficiency.

Background & Aims: Bile salt export pump (BSEP) deficiency frequently necessitates liver transplantation in childhood. In contrast to two predicted protein truncating mutations (PPTMs), homozygous p.D482G or p.E297G mutations are associated with relatively mild phenotypes, responsive to surgical interruption of the enterohepatic circulation (siEHC). The phenotype of patients with a compound heterozygous genotype of one p.D482G or p.E297G mutation and one PPTM has remained unclear. We aimed to assess their genotype-phenotype relationship. Methods: From the NAPPED database, we selected patients with homozygous p.D482G or p.E297G mutations (BSEP1/1; n = 31), with one p.D482G or p.E297G, and one PPTM (BSEP1/3; n = 30), and with two PPTMs (BSEP3/3; n = 77). We compared clinical presentation, native liver survival (NLS), and the effect of siEHC on NLS. Results: The groups had a similar median age at presentation (0.7-1.3 years). Overall NLS at age 10 years was 21% in BSEP1/3 vs. 75% in BSEP1/1 and 23% in BSEP3/3 (p <0.001). Without siEHC, NLS in the BSEP1/3 group was similar to that in BSEP3/3, but considerably lower than in BSEP1/1 (at age 10 years: 38%, 30%, and 71%, respectively; p = 0.003). After siEHC, BSEP1/3 and BSEP3/3 were associated with similarly low NLS, while NLS was much higher in BSEP1/1 (10 years after siEHC, 27%, 14%, and 92%, respectively; p <0.001). Conclusions: Individuals with BSEP deficiency with one p.E297G or p.D482G mutation and one PPTM have a similarly severe disease course and low responsiveness to siEHC as those with two PPTMs. This identifies a considerable subgroup of patients who are unlikely to benefit from interruption of the enterohepatic circulation by either surgical or ileal bile acid transporter inhibitor treatment. Impact and implications: This manuscript defines the clinical features and prognosis of individuals with BSEP deficiency involving the combination of one relatively mild and one very severe BSEP deficiency mutation. Until now, it had always been assumed that the mild mutation would be enough to ensure a relatively good prognosis. However, our manuscript shows that the prognosis of these patients is just as poor as that of patients with two severe mutations. They do not respond to biliary diversion surgery and will likely not respond to the new IBAT (ileal bile acid transporter) inhibitors, which have recently been approved for use in BSEP deficiency.

Long-term outcomes of patients with type 1 or 2 autoimmune hepatitis presenting in childhood.

BACKGROUND & AIMS: In children with autoimmune hepatitis, uncertainties include outcomes associated with type 2 hepatitis, the possibility of and criteria for attempting withdrawal of treatment, and long-term outcomes. We report our experience on these issues. METHODS: From 1973 to 2002, 117 children with type 1 (n = 65) or type 2 (n = 52) hepatitis, excluding fulminant hepatitis, were treated, primarily with prednisone and azathioprine. Median follow-up was 20 years in survivors. RESULTS: Normalisation of aminotransferases and prothrombin ratio were observed in 93% and 84% of children, respectively; sustained remission after treatment withdrawal was recorded in 24% of the entire population, with a median follow-up of 7 years. Sustained treatment-free remission was obtained in 11 of 24 children with follow-ups of 4-22 years based on durable normalisation of aminotransferases (without histological assessment). Gastrointestinal bleeding from varices and the emergence of extrahepatic autoimmune disorders occurred in 10 and 22 patients, respectively. Liver transplantation was performed in 23 patients at a median age of 21 years. The 30-year probabilities of overall and native liver survival were 81% and 61%, respectively. No differences were observed between type 1 and 2 hepatitis for any of the component parts of outcome. In the multivariate analysis, a persistent abnormal prothrombin ratio was associated with worse probabilities of overall and native liver survival. CONCLUSIONS: In terms of liver outcome, type 2 hepatitis is not different from type 1. Withdrawal of treatment is possible without prior liver histology. A persistent abnormal prothrombin ratio identifies patients who will require liver transplantation in adolescence or early adulthood. IMPACT AND IMPLICATIONS: In children with autoimmune hepatitis, there are conflicting reports on the differences in outcome between type 1 and type 2 hepatitis, and on the possibility of treatment withdrawal, before which liver histology is required; data concerning >10-year overall and native liver survival rates are limited. In this study, we found no differences in outcomes between type 1 and 2 hepatitis; a durable treatment-free state was achieved in 19% of all patients throughout childhood and early adulthood, and in 45% of children for whom treatment withdrawal was attempted without prior liver histology; prothrombin was found to be predictive of 30-year overall and native liver survival. The results allow for a less-strict approach to treatment withdrawal in children, avoiding the risks of a liver biopsy, and they provide a tool to help anticipate the need for liver transplantation before complications occur.

A Retrospective Multicentric Study of 34 Patients with Niemann-Pick Type C Disease and Early Liver Involvement in France.

OBJECTIVE: To describe the clinical features and course of liver involvement in a cohort of patients with Niemann-Pick type C disease (NP-C), a severe lysosomal storage disorder. STUDY DESIGN: Patients with genetically confirmed NP-C (NPC1, n = 31; NPC2, n = 3) and liver involvement before age 6 months were retrospectively included. Clinical, laboratory test, and imaging data were collected until the last follow-up or death; available liver biopsy specimens were studied using anti-CD68 immunostaining. RESULTS: At initial evaluation (median age, 17 days of life), all patients had hepatomegaly, 33 had splenomegaly, and 30 had neonatal cholestasis. Portal hypertension and liver failure developed in 9 and 4 patients, respectively. Liver biopsy studies, performed in 16 patients, revealed significant fibrosis in all 16 and CD68+ storage cells in 15. Serum alpha-fetoprotein concentration measured in 21 patients was elevated in 17. Plasma oxysterol concentrations were increased in the 16 patients tested. Four patients died within 6 months of life, including 3 from liver involvement. In patients who survived beyond age 6 months (median follow-up, 6.1 years), cholestasis regressed in all, and portal hypertension regressed in all but 1; 25 patients developed neurologic involvement, which was fatal in 16 patients. CONCLUSIONS: Liver involvement in NP-C consisted of transient neonatal cholestasis with hepatosplenomegaly, was associated with liver fibrosis, and was responsible for death in 9% of patients. The combination of liver anti-CD68 immunostaining, serum alpha-fetoprotein measurement, and studies of plasma biomarkers should facilitate early identification of NP-C.

Maralixibat Treatment Response in Alagille Syndrome is Associated with Improved Health-Related Quality of Life.

OBJECTIVE: The objective of this study was to assess the impact of treatment response to the ileal bile acid transporter inhibitor maralixibat on health-related quality of life (HRQoL) in children with Alagille syndrome. STUDY DESIGN: This analysis used data from the ICONIC trial, a phase 2 study with a 4-week double-blind, placebo-controlled, randomized drug withdrawal period in children with Alagille syndrome with moderate-to-severe pruritus. Clinically meaningful treatment response to maralixibat was defined a priori as a ≥1-point reduction in the Itch-Reported Outcome (Observer) score, from baseline to week 48. HRQoL was assessed using the Pediatric Quality of Life Inventory Generic Core, Family Impact, and Multidimensional Fatigue scale scores, which were collected via the caregiver. The minimal clinically important difference for HRQoL ranged from 4 to 5 points, depending on the scale. RESULTS: Twenty of the 27 patients (74%) included in this analysis achieved an Itch-Reported Outcome (Observer) treatment response at week 48. The mean (SD) change in Multidimensional Fatigue score was +25.8 (23.0) for responders vs -3.1 (19.8) for nonresponders (P = .03). Smaller and non-statistically significant mean changes were observed for the Pediatric Quality of Life Inventory Generic Core and Family Impact scores. Controlling for baseline Family Impact score, responders' Family Impact scores increased an average of 16.9 points over 48 weeks compared with non-responders (P = .05). Smaller and non-statistically significant point estimates were observed for the Pediatric Quality of Life Inventory Generic Core and Multidimensional Fatigue scores. CONCLUSION: The significant improvements in pruritus seen with maralixibat at week 48 of the ICONIC study are clinically meaningful and are associated with improved HRQoL. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02160782.

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.

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.

In Vitro Rescue of the Bile Acid Transport Function of ABCB11 Variants by CFTR Potentiators.

ABCB11 is responsible for biliary bile acid secretion at the canalicular membrane of hepatocytes. Variations in the ABCB11 gene cause a spectrum of rare liver diseases. The most severe form is progressive familial intrahepatic cholestasis type 2 (PFIC2). Current medical treatments have limited efficacy. Here, we report the in vitro study of Abcb11 missense variants identified in PFIC2 patients and their functional rescue using cystic fibrosis transmembrane conductance regulator potentiators. Three ABCB11 disease-causing variations identified in PFIC2 patients (i.e., A257V, T463I and G562D) were reproduced in a plasmid encoding an Abcb11-green fluorescent protein. After transfection, the expression and localization of the variants were studied in HepG2 cells. Taurocholate transport activity and the effect of potentiators were studied in Madin-Darby canine kidney (MDCK) clones coexpressing Abcb11 and the sodium taurocholate cotransporting polypeptide (Ntcp/Slc10A1). As predicted using three-dimensional structure analysis, the three variants were expressed at the canalicular membrane but showed a defective function. Ivacaftor, GLP1837, SBC040 and SBC219 potentiators increased the bile acid transport of A257V and T463I and to a lesser extent, of G562D Abcb11 missense variants. In addition, a synergic effect was observed when ivacaftor was combined with SBC040 or SBC219. Such potentiators could represent new pharmacological approaches for improving the condition of patients with ABCB11 deficiency due to missense variations affecting the function of the transporter.

Efficacy and Safety of Endoscopic Primary Prophylaxis of Bleeding in Children With High-Risk Gastroesophageal Varices.

OBJECTIVES: Primary prophylaxis of bleeding is debated in children with gastroesophageal varices; one of the reasons is the limited number of studies concerning its efficacy and safety. We report our experience with endoscopic primary prophylaxis. METHODS: From 2006 to 2019, 145 children (median age, 3.5 years; cirrhosis, n = 116) with high-risk gastroesophageal varices underwent primary prophylaxis (banding, n = 114; sclerotherapy n = 31, primarily in smaller children). RESULTS: We observed the eradication of varices in 93% of children after a mean of 6 months, at least one recurrence of varices in 45% after eradication, and gastrointestinal bleeding in 17% of children. Irrespective of the cause of portal hypertension, grade 3 esophageal varices, presence of gastric varices along the cardia and a lower composite score of endoscopic severity were associated with a worse probability of eradication, a longer time to eradication and a lower risk of a first recurrence and of bleeding following the procedure, respectively. Ten-year probabilities of overall survival and of bleeding-free survival were 95% and 75%, respectively. CONCLUSIONS: Endoscopic primary prophylaxis of variceal bleeding is reasonably effective and safe in children with high-risk gastroesophageal varices. Worse results are observed in children with more advanced endoscopic features. This pleads for endoscopic screening in children with portal hypertension and early detection of varices warranting primary prophylaxis.