Maralixibat in progressive familial intrahepatic cholestasis (MARCH-PFIC): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: Progressive familial intrahepatic cholestasis (PFIC) is a group of autosomal recessive disorders, the most prevalent being BSEP deficiency, resulting in disrupted bile formation, cholestasis, and pruritus. Building on a previous phase 2 study, we aimed to evaluate the efficacy and safety of maralixibat-an ileal bile acid transporter inhibitor-in participants with all types of PFIC. METHODS: MARCH-PFIC was a multicentre, randomised, double-blind, placebo-controlled, phase 3 study conducted in 29 community and hospital centres across 16 countries in Europe, the Americas, and Asia. We recruited participants aged 1-17 years with PFIC with persistent pruritus (>6 months; average of ≥1·5 on morning Itch-Reported Outcome [Observer; ItchRO(Obs)] during the last 4 weeks of screening) and biochemical abnormalities or pathological evidence of progressive liver disease, or both. We defined three analysis cohorts. The BSEP (or primary) cohort included only those with biallelic, non-truncated BSEP deficiency without low or fluctuating serum bile acids or previous biliary surgery. The all-PFIC cohort combined the BSEP cohort with participants with biallelic FIC1, MDR3, TJP2, or MYO5B deficiencies without previous surgery but regardless of bile acids. The full cohort had no exclusions. Participants were randomly assigned (1:1) to receive oral maralixibat (starting dose 142·5 µg/kg, then escalated to 570 µg/kg) or placebo twice daily for 26 weeks. The primary endpoint was the mean change in average morning ItchRO(Obs) severity score between baseline and weeks 15-26 in the BSEP cohort. The key secondary efficacy endpoint was the mean change in total serum bile acids between baseline and the average of weeks 18, 22, and 26 in the BSEP cohort. Efficacy analyses were done in the intention-to-treat population (all those randomly assigned) and safety analyses were done in all participants who received at least one dose of study drug. This completed trial is registered with ClinicalTrials.gov, NCT03905330, and EudraCT, 2019-001211-22. FINDINGS: Between July 9, 2019, and March 4, 2022, 125 patients were screened, of whom 93 were randomly assigned to maralixibat (n=47; 14 in the BSEP cohort and 33 in the all-PFIC cohort) or placebo (n=46; 17 in the BSEP cohort and 31 in the all-PFIC cohort), received at least one dose of study drug, and were included in the intention-to-treat and safety populations. The median age was 3·0 years (IQR 2·0-7·0) and 51 (55%) of 93 participants were female and 42 (45%) were male. In the BSEP cohort, least-squares mean change from baseline in morning ItchRO(Obs) was -1·7 (95% CI -2·3 to -1·2) with maralixibat versus -0·6 (-1·1 to -0·1) with placebo, with a significant between-group difference of -1·1 (95% CI -1·8 to -0·3; p=0·0063). Least-squares mean change from baseline in total serum bile acids was -176 µmol/L (95% CI -257 to -94) for maralixibat versus 11 µmol/L (-58 to 80) for placebo, also representing a significant difference of -187 µmol/L (95% CI -293 to -80; p=0·0013). The most common adverse event was diarrhoea (27 [57%] of 47 patients on maralixibat vs nine [20%] of 46 patients on placebo; all mild or moderate and mostly transient). There were five (11%) participants with serious treatment-emergent adverse events in the maralixibat group versus three (7%) in the placebo group. No treatment-related deaths occurred. INTERPRETATION: Maralixibat improved pruritus and predictors of native liver survival in PFIC (eg, serum bile acids). Maralixibat represents a non-surgical, pharmacological option to interrupt the enterohepatic circulation and improve the standard of care in patients with PFIC. FUNDING: Mirum Pharmaceuticals.

Sepsis during short bowel syndrome hospitalizations: Identifying trends, disparities, and clinical outcomes in the United States.

BACKGROUND: Short bowel syndrome (SBS) hospitalizations are often complicated with sepsis. There is a significant paucity of data on adult SBS hospitalizations in the United States and across the globe. AIM: To assess trends and outcomes of SBS hospitalizations complicated by sepsis in the United States. METHODS: The National Inpatient Sample was utilized to identify all adult SBS hospitalizations between 2005-2014. The study cohort was further divided based on the presence or absence of sepsis. Trends were identified, and hospitalization characteristics and clinical outcomes were compared. Predictors of mortality for SBS hospitalizations complicated with sepsis were assessed. RESULTS: Of 247097 SBS hospitalizations, 21.7% were complicated by sepsis. Septic SBS hospitalizations had a rising trend of hospitalizations from 20.8% in 2005 to 23.5% in 2014 (P trend < 0.0001). Compared to non-septic SBS hospitalizations, septic SBS hospitalizations had a higher proportion of males (32.8% vs 29.3%, P < 0.0001), patients in the 35-49 (45.9% vs 42.5%, P < 0.0001) and 50-64 (32.1% vs 31.1%, P < 0.0001) age groups, and ethnic minorities, i.e., Blacks (12.4% vs 11.3%, P < 0.0001) and Hispanics (6.7% vs 5.5%, P < 0.0001). Furthermore, septic SBS hospitalizations had a higher proportion of patients with intestinal transplantation (0.33% vs 0.22%, P < 0.0001), inpatient mortality (8.5% vs 1.4%, P < 0.0001), and mean length of stay (16.1 d vs 7.7 d, P < 0.0001) compared to the non-sepsis cohort. A younger age, female gender, White race, and presence of comorbidities such as anemia and depression were identified to be independent predictors of inpatient mortality for septic SBS hospitalizations. CONCLUSION: Septic SBS hospitalizations had a rising trend between 2005-2014 and were associated with higher inpatient mortality compared to non-septic SBS hospitalizations.

From intestinal failure to transplantation: Review on the current need for transplant indications under multidisciplinary transplant programs worldwide.

INTRODUCTION: Intestinal failure, defined as the loss of gastrointestinal function to the point where nutrition cannot be maintained by enteral intake alone, presents numerous challenges in children, not least the timing of consideration of intestine transplantation. OBJECTIVES: To describe the evolution of care of infants and children with intestinal failure including parenteral nutrition, intestine transplantation, and contemporary intestinal failure care. METHODS: The review is based on the authors' experience supported by an in-depth review of the published literature. RESULTS: The history of parenteral nutrition, including out-patient (home) administration, and intestine transplantation are reviewed along with the complications of intestinal failure that may become indications for consideration of intestine transplantation. Current management strategies for children with intestinal failure are discussed along with changes in need for intestine transplantation, recognizing the difficulty in generalizing recommendations due to the high level of heterogeneity of intestinal pathology and residual bowel anatomy and function. DISCUSSION: Advances in the medical and surgical care of children with intestinal failure have resulted in improved transplant-free survival and a significant fall in demand for transplantation. Despite these improvements a number of children continue to fail rehabilitative care and require intestine transplantation as life-saving therapy or when the burden on ongoing parenteral nutrition becomes too great to bear.

Oral vancomycin is associated with improved inflammatory bowel disease clinical outcomes in primary sclerosing cholangitis-associated inflammatory bowel disease (PSC-IBD): A matched analysis from the Paediatric PSC Consortium.

BACKGROUND: Data on oral vancomycin for primary sclerosing cholangitis (PSC)-associated inflammatory bowel disease (IBD) are limited. AIMS: Using data from the Paediatric PSC Consortium, to examine the effect of vancomycin on IBD activity. METHODS: In this retrospective multi-centre cohort study, we matched vancomycin-treated and untreated patients (1:3) based on IBD duration at the time of primary outcome assessment. The primary outcome was Physician Global Assessment (PGA) of IBD clinical activity after 1 year (±6 months) of vancomycin. We used generalised estimating equations (GEE) to examine the association between vancomycin and PGA remission, adjusting for IBD type, severity and medication exposures. Secondary outcomes included serum labs and endoscopic remission (global rating of no activity) among those with available data and also analysed with GEE. RESULTS: 113 PSC-IBD patients received vancomycin (median age 12.7 years, 63% male). The matched cohort included 70 vancomycin-treated and 210 untreated patients. Vancomycin was associated with greater odds of IBD clinical remission (odds ratio [OR] 3.52, 95% CI 1.97-6.31; adjusted OR [aOR] 5.24, 95% CI 2.68-10.22). Benefit was maintained in sensitivity analyses restricted to non-transplanted patients and those with baseline moderate-severe PGA. Vancomycin was associated with increased odds of endoscopic remission (aOR 2.76, 95% CI 1.002-7.62; N = 101 with data), and with lower CRP (p = 0.03) and higher haemoglobin and albumin (both p < 0.01). CONCLUSION: Vancomycin was associated with greater odds of IBD clinical and endoscopic remission. Additional, preferably randomised, controlled studies are needed to characterise efficacy using objective markers of mucosal inflammation, and to examine safety and define optimal dosing.

OPTN/SRTR 2022 Annual Data Report: Intestine.

Intestine remains the least frequently transplanted solid organ, although the survival and quality-of-life benefits of transplant to individuals with irreversible intestinal failure have been well demonstrated. The trend seen over the past 15 years of fewer listings and fewer transplants appears to be continuing, most noticeably in infants, children, and adolescents. There were only 146 additions to the intestine waiting list in 2022, and the proportion of adult candidates continues to increase, so that now 61% of the intestine waiting list are adult candidates. There has been little change in the distribution by sex, race and ethnicity, or primary diagnosis on the waiting list, or for those receiving transplant. The transplant rate for adults has decreased to 55.6 transplants per 100 patient-years, but the pediatric transplant rate remains relatively stable at 22.8 transplants per 100 patient-years. The decrease in transplant rates for adults is primarily the result of falling rates for those listed for combined intestine-liver, and this is reflected in the pretransplant mortality rates, which are twice as high for candidates in need of both organs compared with those listed for intestine alone. Overall, intestine transplant numbers decreased to a total of 82 intestine transplants in 2022, only one above the lowest ever value of 81 in 2019. No major changes were seen in the immunosuppression protocols, with most recipients having induction therapy and tacrolimus-based maintenance. Graft failure rates appear to have improved at 1, 3, and 5 years for intestine without liver, but this is not seen for combined intestine-liver. Graft and patient survival are better for pediatric recipients compared with adult recipients for both liver-inclusive and liver-exclusive transplant. Rates of posttransplant lymphoproliferative disorder are higher for recipients of intestine without liver.

Diagnostic accuracy of serum matrix metalloproteinase-7 as a biomarker of biliary atresia in a large North American cohort.

BACKGROUND AND AIMS: High levels of serum matrix metalloproteinase-7 (MMP-7) have been linked to biliary atresia (BA), with wide variation in concentration cutoffs. We investigated the accuracy of serum MMP-7 as a diagnostic biomarker in a large North American cohort. APPROACH AND RESULTS: MMP-7 was measured in serum samples of 399 infants with cholestasis in the Prospective Database of Infants with Cholestasis study of the Childhood Liver Disease Research Network, 201 infants with BA and 198 with non-BA cholestasis (age median: 64 and 59 days, p = 0.94). MMP-7 was assayed on antibody-bead fluorescence (single-plex) and time resolved fluorescence energy transfer assays. The discriminative performance of MMP-7 was compared with other clinical markers. On the single-plex assay, MMP-7 generated an AUROC of 0.90 (CI: 0.87-0.94). At cutoff 52.8 ng/mL, it produced sensitivity = 94.03%, specificity = 77.78%, positive predictive value = 64.46%, and negative predictive value = 96.82% for BA. AUROC for gamma-glutamyl transferase = 0.81 (CI: 0.77-0.86), stool color = 0.68 (CI: 0.63-0.73), and pathology = 0.84 (CI: 0.76-0.91). Logistic regression models of MMP-7 with other clinical variables individually or combined showed an increase for MMP-7+gamma-glutamyl transferase AUROC to 0.91 (CI: 0.88-0.95). Serum concentrations produced by time resolved fluorescence energy transfer differed from single-plex, with an optimal cutoff of 18.2 ng/mL. Results were consistent within each assay technology and generated similar AUROCs. CONCLUSIONS: Serum MMP-7 has high discriminative properties to differentiate BA from other forms of neonatal cholestasis. MMP-7 cutoff values vary according to assay technology. Using MMP-7 in the evaluation of infants with cholestasis may simplify diagnostic algorithms and shorten the time to hepatoportoenterostomy.

Impact of early immunosuppression on pediatric liver transplant outcomes within 1 year.

OBJECTIVES: The Starzl Network for Excellence in Pediatric Transplantation identified optimizing immunosuppression (IS) as a priority practice improvement area for patients, families, and providers. We aimed to evaluate associations between clinical characteristics, early IS, and outcomes. METHODS: We analyzed pediatric liver transplant (LT) data from 2013 to 2018 in the United Network for Organ Sharing (UNOS) and the Society of Pediatric Liver Transplantation (SPLIT) registries. RESULTS: We included 2542 LT recipients in UNOS and 1590 in SPLIT. IS choice varied between centers with steroid induction and mycophenolate mofetil (MMF) use each ranging from 0% to 100% across centers. Clinical characteristics associated with early IS choice were inconsistent between the two data sets. T-cell depleting antibody use was associated with improved 1-year graft (hazard ratio [HR] 0.50, 95% confidence interval [CI] 0.34-0.76) and patient (HR 0.40, 95% CI 0.20-0.79) survival in UNOS but decreased 1-year patient survival (HR 4.12, 95% CI 1.31-12.93) and increased acute rejection (HR 1.58, 95% CI 1.07-2.34) in SPLIT. Non-T-cell depleting antibody use was not associated with differential risk of survival nor rejection. MMF use was associated with improved 1-year graft survival (HR 0.73, 95% CI 0.54-0.99) in UNOS only. CONCLUSIONS: Variation exists in center choice of early IS regimen. UNOS and SPLIT data provide conflicting associations between IS and outcomes in multivariable analysis. These results highlight the need for future multicenter collaborative work to identify evidence-based IS best practices.

Enhanced Donor Antigen Presentation by B Cells Predicts Acute Cellular Rejection and Late Outcomes After Transplantation.

Background: Enhanced B-cell presentation of donor alloantigen relative to presentation of HLA-mismatched reference alloantigen is associated with acute cellular rejection (ACR), when expressed as a ratio called the antigen presenting index (API) in an exploratory cohort of liver and intestine transplant (LT and IT) recipients. Methods: To test clinical performance, we measured the API using the previously described 6-h assay in 84 LT and 54 IT recipients with median age 3.3 y (0.05-23.96). Recipients experiencing ACR within 60 d after testing were termed rejectors. Results: We first confirmed that B-cell uptake and presentation of alloantigen induced and thus reflected the alloresponse of T-helper cells, which were incubated without and with cytochalasin and primaquine to inhibit antigen uptake and presentation, respectively. Transplant recipients included 76 males and 62 females. Rejectors were tested at median 3.6 d before diagnosis. The API was higher among rejectors compared with nonrejectors (2.2 ±â€…0.2 versus 0.6 ±â€…0.04, P value = 1.7E-09). In logistic regression and receiver-operating-characteristic analysis, API ≥1.1 achieved sensitivity, specificity, and positive and negative predictive values for predicting ACR in 99 training set samples. Corresponding metrics ranged from 80% to 88% in 32 independent posttransplant samples, and 73% to 100% in 20 independent pretransplant samples. In time-to-event analysis, API ≥1.1 predicted higher incidence of late donor-specific anti-HLA antibodies after API measurements in LT recipients (P = 0.011) and graft loss in IT recipients (P = 0.008), compared with recipients with API <1.1, respectively. Conclusions: Enhanced donor antigen presentation by circulating B cells predicts rejection after liver or intestine transplantation as well as higher incidence of DSA and graft loss late after transplantation.

Protein biomarkers GDF15 and FGF21 to differentiate mitochondrial hepatopathies from other pediatric liver diseases.

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

Neonatal cholestasis in children with Alpha-1-AT deficiency is a risk for earlier severe liver disease with male predominance.

BACKGROUND: Our objective was to better understand the natural history and disease modifiers of Alpha-1-antitrypsin deficiency (AATD), a common genetic liver disease causing hepatitis and cirrhosis in adults and children. The clinical course is highly variable. Some infants present with neonatal cholestasis, which can resolve spontaneously or progress to cirrhosis; others are well in infancy, only to develop portal hypertension later in childhood. METHODS: The Childhood Liver Disease Research Network has been enrolling AATD participants into longitudinal, observational studies at North American tertiary centers since 2004. We examined the clinical courses of 2 subgroups of participants from the several hundred enrolled; first, those presenting with neonatal cholestasis captured by a unique study, enrolled because of neonatal cholestasis but before specific diagnosis, then followed longitudinally (n=46); second, separately, all participants who progressed to liver transplant (n=119). RESULTS: We found male predominance for neonatal cholestasis in AATD (65% male, p=0.04), an association of neonatal gamma-glutamyl transpeptidase elevation to more severe disease, and a higher rate of neonatal cholestasis progression to portal hypertension than previously reported (41%) occurring at median age of 5 months. Participants with and without preceding neonatal cholestasis were at risk of progression to transplant. Participants who progressed to liver transplant following neonatal cholestasis were significantly younger at transplant than those without neonatal cholestasis (4.1 vs. 7.8 years, p=0.04, overall range 0.3-17 years). Neonatal cholestasis had a negative impact on growth parameters. Coagulopathy and varices were common before transplant, but gastrointestinal bleeding was not. CONCLUSIONS: Patients with AATD and neonatal cholestasis are at risk of early progression to severe liver disease, but the risk of severe disease extends throughout childhood. Careful attention to nutrition and growth is needed.

Sarcopenia is associated with osteopenia and impaired quality of life in children with genetic intrahepatic cholestatic liver disease.

BACKGROUND: Sarcopenia occurs in pediatric chronic liver disease, although the prevalence and contributing factors in genetic intrahepatic cholestasis are not well-described. The objective of this study was to measure muscle mass in school-aged children with genetic intrahepatic cholestasis and assess relationships between sarcopenia, clinical variables, and outcomes. METHODS: Estimated skeletal muscle mass (eSMM) was calculated on dual-energy x-ray absorptiometry obtained in a Childhood Liver Disease Research Network study of children with bile acid synthesis disorders(BASD) alpha-1 antitrypsin deficiency (a1ATd), chronic intrahepatic cholestasis (CIC), and Alagille syndrome (ALGS). Relationships between eSMM, liver disease, and transplant-free survival were assessed. RESULTS: eSMM was calculated in 127 participants (5-18 y): 12 BASD, 41 a1ATd, 33 CIC, and 41 ALGS. eSMM z-score was lower in CIC (-1.6 ± 1.3) and ALGS (-2.1 ± 1.0) than BASD (-0.1 ± 1.1) and a1ATd (-0.5 ± 0.8, p < 0.001). Sarcopenia (defined as eSMM z-score ≤- 2) was present in 33.3% of CIC and 41.5% of ALGS participants. eSMM correlated with bone mineral density in the 4 disease groups (r=0.52-0.55, p < 0.001-0.07), but not serum bile acids, bilirubin, aspartate aminotransferase/platelet ratio index, or clinically evident portal hypertension. Of the 2 patients who died (1 with sarcopenia) and 18 who underwent liver transplant (LT, 4 with sarcopenia), eSMM z-score did not predict transplant-free survival. eSMM z-score correlated with the Physical Pediatric Quality of Life Inventory score (r=0.38-0.53, p = 0.007-0.04) in CIC and a1ATd. CONCLUSION: Severe sarcopenia occurs in some children with ALGS and CIC. The lack of correlation between eSMM and biochemical cholestasis suggests mechanisms beyond cholestasis contribute to sarcopenia. While sarcopenia did not predict transplant-free survival, LT and death were infrequent events. Future studies may define mechanisms of sarcopenia in genetic intrahepatic cholestasis.

Outcome of Children with Transjugular Intrahepatic Portosystemic Shunt: A Meta-Analysis of Individual Patient Data.

PURPOSE: The purpose of the study was to investigate outcome after pediatric transjugular intrahepatic portosystemic shunt (TIPS) with respect to survival MATERIAL AND METHODS: After searching for studies on TIPS in children in Ovid, Medline, Embase, Scopus and Cochrane published between 2000 and 2022, individual patient data were retrieved from five retrospective cohorts. Overall survival (OS) and transplant-free survival (TFS) were calculated using Kaplan-Meier analysis and log-rank test and compared to the indication (ascites vs. variceal bleeding) as well as to the level of obstruction (pre-hepatic vs. hepatic vs. post-hepatic). Additionally, TIPS patency was analyzed. RESULTS: n = 135 pediatric patients were included in the final analysis. Indication for pediatric TIPS creation was heterogeneous among the included studies. TIPS patency decreased from 6 to 24 months, subsequent pediatric liver transplantation was performed in 22/135 (16.3%) of cases. The presence of ascites was related with poorer TFS (HR 2.3, p = 0.023), while variceal bleeding was not associated with impaired survival. Analysis of the level of obstruction (pre-hepatic, hepatic and post-hepatic) failed to prove significantly reduced OS for post-hepatic obstruction (HR 3.2, p = 0.092) and TFS (HR 1.3, p = 0.057). There was no difference in OS and TFS according to age at time of TIPS placement. CONCLUSIONS: The presence of ascites associates with impaired survival after TIPS in children, with no differences in survival according to the age of the child. Interventional shunt procedures can be considered feasible for all ages. LEVEL OF EVIDENCE: Level 2a.

Biliary atresia is associated with polygenic susceptibility in ciliogenesis and planar polarity effector genes.

BACKGROUND & AIMS: Biliary atresia (BA) is poorly understood and leads to liver transplantation (LT), with the requirement for and associated risks of lifelong immunosuppression, in most children. We performed a genome-wide association study (GWAS) to determine the genetic basis of BA. METHODS: We performed a GWAS in 811 European BA cases treated with LT in US, Canadian and UK centers, and 4,654 genetically matched controls. Whole-genome sequencing of 100 cases evaluated synthetic association with rare variants. Functional studies included whole liver transcriptome analysis of 64 BA cases and perturbations in experimental models. RESULTS: A GWAS of common single nucleotide polymorphisms (SNPs), i.e. allele frequencies >1%, identified intronic SNPs rs6446628 in AFAP1 with genome-wide significance (p = 3.93E-8) and rs34599046 in TUSC3 at sub-threshold genome-wide significance (p = 1.34E-7), both supported by credible peaks of neighboring SNPs. Like other previously reported BA-associated genes, AFAP1 and TUSC3 are ciliogenesis and planar polarity effectors (CPLANE). In gene-set-based GWAS, BA was associated with 6,005 SNPs in 102 CPLANE genes (p = 5.84E-15). Compared with non-CPLANE genes, more CPLANE genes harbored rare variants (allele frequency <1%) that were assigned Human Phenotype Ontology terms related to hepatobiliary anomalies by predictive algorithms, 87% vs. 40%, p <0.0001. Rare variants were present in multiple genes distinct from those with BA-associated common variants in most BA cases. AFAP1 and TUSC3 knockdown blocked ciliogenesis in mouse tracheal cells. Inhibition of ciliogenesis caused biliary dysgenesis in zebrafish. AFAP1 and TUSC3 were expressed in fetal liver organoids, as well as fetal and BA livers, but not in normal or disease-control livers. Integrative analysis of BA-associated variants and liver transcripts revealed abnormal vasculogenesis and epithelial tube formation, explaining portal vein anomalies that co-exist with BA. CONCLUSIONS: BA is associated with polygenic susceptibility in CPLANE genes. Rare variants contribute to polygenic risk in vulnerable pathways via unique genes. IMPACT AND IMPLICATIONS: Liver transplantation is needed to cure most children born with biliary atresia, a poorly understood rare disease. Transplant immunosuppression increases the likelihood of life-threatening infections and cancers. To improve care by preventing this disease and its progression to transplantation, we examined its genetic basis. We find that this disease is associated with both common and rare mutations in highly specialized genes which maintain normal communication and movement of cells, and their organization into bile ducts and blood vessels during early development of the human embryo. Because defects in these genes also cause other birth defects, our findings could lead to preventive strategies to lower the incidence of biliary atresia and potentially other birth defects.

Outcome After Intestinal Transplantation From Living Versus Deceased Donors: A Propensity-matched Cohort Analysis of the International Intestinal Transplant Registry.

OBJECTIVE: To describe the worldwide experience with living donation (LD) in intestinal transplantation (ITx) and compare short-term and long-term outcomes to a propensity-matched cohort of deceased donors. BACKGROUND: ITx is a rare life-saving procedure for patients with complicated intestinal failure (IF). Living donation (LD)-ITx has been performed with success, but no direct comparison with deceased donation (DD) has been performed. The Intestinal Transplant Registry (ITR) was created in 1985 by the Intestinal Transplant Association to capture the worldwide activity and promote center's collaborations. METHODS: Based on the ITR, 4156 ITx were performed between January 1987 and April 2019, of which 76 (1.8%) were LD, including 5 combined liver-ITx, 7 ITx-colon, and 64 isolated ITx. They were matched with 186 DD-ITx for recipient age/sex, weight, region, IF-cause, retransplant, pretransplant status, ABO compatibility, immunosuppression, and transplant date. Primary endpoints were acute rejection and 1-/5-year patient/graft survival. RESULTS: Most LDs were performed in North America (61%), followed by Asia (29%). The mean recipient age was: 22 years; body mass index: 19kg/m²; and female/male ratio: 1/1.4. Volvulus (N=17) and ischemia (N=17) were the most frequent IF-causes. Fifty-two percent of patients were at home at the time of transplant. One-/5-year patient survival for LD and DD was 74.2/49.8% versus 80.3/48.1%, respectively ( P =0.826). One-/5-year graft survival was 60.3/40.6% versus 69.2/36.1%, respectively ( P =0.956). Acute rejection was diagnosed in 47% of LD versus 51% of DD ( P =0.723). CONCLUSION: Worldwide, LD-ITx has been rarely performed. This retrospective matched ITR analysis revealed no difference in rejection and in patient/graft survival between LD and DD-ITx.

OPTN/SRTR 2021 Annual Data Report: Intestine.

There has been just over 30 years of experience in clinical intestine transplant. A rise in demand until 2007 with improving transplant outcomes preceded a subsequent fall in demand due, at least in part, to improvements in pretransplant care of patients with intestinal failure. Over the past 10 to 12 years, there has been no suggestion of an increase in demand and, particularly for adult transplant, there may be a continued trend toward fewer additions to the waiting list and fewer transplants, especially in those needing combined intestine-liver transplant. In addition, over the same period there has been no noticeable improvement in graft survival, with 1- and 5-year graft failure rates averaging 21.6% and 52.5%, respectively, for intestine-alone transplants and 28.6% and 47.2%, respectively, for combined intestine-liver allografts.

Clinical spectrum and genetic causes of mitochondrial hepatopathy phenotype in children.

BACKGROUND: Alterations in both mitochondrial DNA (mtDNA) and nuclear DNA genes affect mitochondria function, causing a range of liver-based conditions termed mitochondrial hepatopathies (MH), which are subcategorized as mtDNA depletion, RNA translation, mtDNA deletion, and enzymatic disorders. We aim to enhance the understanding of pathogenesis and natural history of MH. METHODS: We analyzed data from patients with MH phenotypes to identify genetic causes, characterize the spectrum of clinical presentation, and determine outcomes. RESULTS: Three enrollment phenotypes, that is, acute liver failure (ALF, n = 37), chronic liver disease (Chronic, n = 40), and post-liver transplant (n = 9), were analyzed. Patients with ALF were younger [median 0.8 y (range, 0.0, 9.4) vs 3.4 y (0.2, 18.6), p < 0.001] with fewer neurodevelopmental delays (40.0% vs 81.3%, p < 0.001) versus Chronic. Comprehensive testing was performed more often in Chronic than ALF (90.0% vs 43.2%); however, etiology was identified more often in ALF (81.3% vs 61.1%) with mtDNA depletion being most common (ALF: 77% vs Chronic: 41%). Of the sequenced cohort (n = 60), 63% had an identified mitochondrial disorder. Cluster analysis identified a subset without an underlying genetic etiology, despite comprehensive testing. Liver transplant-free survival was 40% at 2 years (ALF vs Chronic, 16% vs 65%, p < 0.001). Eighteen (21%) underwent transplantation. With 33 patient-years of follow-up after the transplant, 3 deaths were reported. CONCLUSIONS: Differences between ALF and Chronic MH phenotypes included age at diagnosis, systemic involvement, transplant-free survival, and genetic etiology, underscoring the need for ultra-rapid sequencing in the appropriate clinical setting. Cluster analysis revealed a group meeting enrollment criteria but without an identified genetic or enzymatic diagnosis, highlighting the need to identify other etiologies.

Pediatric intestine transplant cost: Analysis of the Pediatric Health Information System database.

BACKGROUND: We aimed to evaluate costs from transplant to discharge in children who had undergone intestine transplant. METHODS: We performed a cross-sectional observational study of pediatric intestine transplant recipients from 2004 through 2020, utilizing the Pediatric Health Information System database. Standardized costs were applied to all charges and converted to 2021 US dollars. We analyzed the association of cost from transplant to discharge with age, sex, race and ethnicity, length of stay, insurance type, transplant year, short bowel syndrome diagnosis, liver-containing graft, hospitalization status, and immunosuppressive regimen. Predictors with a P value <0.20 in univariable analysis were included in a multivariable model, which was reduced using backwards selection with a P value of 0.05. RESULTS: We identified 376 intestinal transplant recipients across nine centers (median age, 2 years; 44% female). Most patients had short bowel syndrome (294; 78%). The liver was included in 218 transplants (58%). Median posttransplant cost was $263,724 (interquartile range [IQR], $179,564-$384,147), and length of stay was 51.5 days (IQR, 34-77). In the final model, increased cost from transplant to hospital discharge was associated with liver-containing graft (+$31,805; P = 0.028), T-cell-depleting antibody use (+$77,004; P < 0.001), and mycophenolate mofetil use (+$50,514; P = 0.012) while controlling for insurance type and length of stay. A 60-day posttransplant hospital stay would cost an estimated $272,533. CONCLUSIONS: Intestine transplant has high immediate cost and long length of stay that varies by center, graft type, and immunosuppression regimen. Future work will examine the cost-effectiveness of various management strategies before and after transplant.