Anti-spike antibody durability after SARS-CoV-2 vaccination in adolescent solid organ transplant recipients.

BACKGROUND: Adolescent solid organ transplant recipients (aSOTRs) who received three doses of the COVID-19 mRNA vaccine experience high seroconversion rates and antibody persistence for up to 3 months. Long-term antibody durability beyond this timeframe following three doses of the SARS-CoV-2 mRNA vaccine remains unknown. We describe antibody responses 6 months following the third vaccine dose (D3) of the BNT162b2 mRNA vaccination among aSOTRs. METHODS: Participants in a multi-center, observational cohort who received the third dose of the vaccine were analyzed for antibodies to the SARS-CoV-2 spike protein receptor-binding domain (Roche Elecsys anti-SARS-CoV-2-S positive: ≥0.8, maximum: >2500 U/mL). Samples were collected at 1-, 3-, and 6-months post-D3. Participants were surveyed at each timepoint and at 12-months post-D3. RESULTS: All 34 participants had positive anti-RBD antibody titers 6 months post-D3. Variations in titers occurred between 3 and 6 months post-D3, with 8/28 (29%) having decreased antibody levels at 6 months compared to 3 months and 2/28 (7%) reporting increased titers at 6 months. The remaining 18/28 (64%) had unchanged antibody titers compared to 3-month post-D3 levels. A total of 4/34 (12%) reported breakthrough infection within 6 months and 3/32 (9%) reported infection after 6-12 months following the third dose of the SARS-CoV-2 mRNA vaccine. CONCLUSIONS: The results suggest that antibody durability persists up to 6 months following three doses of the SARS-CoV-2 mRNA in aSOTRs. Demography and transplant characteristics did not differ for those who experienced antibody weaning. Breakthrough infections did occur, reflecting immune-evasive nature of novel variants such as Omicron.

Association of state Medicaid expansion policies with pediatric liver transplant outcomes.

Children from minoritized/socioeconomically deprived backgrounds suffer disproportionately high rates of uninsurance and graft failure/death after liver transplant. Medicaid expansion was developed to expand access to public insurance. Our objective was to characterize the impact of Medicaid expansion policies on long-term graft/patient survival after pediatric liver transplantation. All pediatric patients (<19 years) who received a liver transplant between January 1, 2005, and December 31, 2020 in the US were identified in the Scientific Registry of Transplant Recipients (N = 8489). Medicaid expansion was modeled as a time-varying exposure based on transplant and expansion dates. We used Cox proportional hazards models to evaluate the impact of Medicaid expansion on a composite outcome of graft failure/death over 10 years. As a sensitivity analysis, we conducted an intention-to-treat analysis from time of waitlisting to death (N = 1 1901). In multivariable analysis, Medicaid expansion was associated with a 30% decreased hazard of graft failure/death (hazard ratio, 0.70; 95% confidence interval, 0.62, 0.79; P < .001) after adjusting for Black race, public insurance, neighborhood deprivation, and living in a primary care shortage area. In intention-to-treat analyses, Medicaid expansion was associated with a 72% decreased hazard of patient death (hazard ratio, 0.28; 95% confidence interval, 0.23-0.35; P < .001). Policies that enable broader health insurance access may help improve outcomes and reduce disparities for children undergoing liver transplantation.

Omicron Infections in Vaccinated Pediatric Solid Organ Transplant Recipients.

SARS-CoV-2 infection during the Omicron period was frequent amongst a cohort of vaccinated pediatric solid organ transplant recipients (pSOTRs) despite robust anti-receptor-binding domain (anti-RBD) antibody response, suggesting poor neutralizing capacity against Omicron subvariants. Breakthrough infections among pSOTRs were overall limited in severity.

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.

Safety and Immunogenicity of Live Viral Vaccines in a Multicenter Cohort of Pediatric Transplant Recipients.

Importance: Live vaccines (measles-mumps-rubella [MMR] and varicella-zoster virus [VZV]) have not been recommended after solid organ transplant due to concern for inciting vaccine strain infection in an immunocompromised host. However, the rates of measles, mumps, and varicella are rising nationally and internationally, leaving susceptible immunocompromised children at risk for life-threating conditions. Objective: To determine the safety and immunogenicity of live vaccines in pediatric liver and kidney transplant recipients. Design, Setting, and Participants: This cohort study included select pediatric liver and kidney transplant recipients who had not completed their primary MMR and VZV vaccine series and/or who displayed nonprotective serum antibody levels at enrollment between January 1, 2002, and February 28, 2023. Eligibility for live vaccine was determined by individual US pediatric solid organ transplant center protocols. Exposures: Exposure was defined as receipt of a posttransplant live vaccine. Transplant recipients received 1 to 3 doses of MMR vaccine and/or 1 to 3 doses of VZV vaccine. Main Outcome and Measure: Safety data were collected following each vaccination, and antibody levels were obtained at 0 to 3 months and 1 year following vaccination. Comparisons were performed using Mann-Whitney U test, and factors associated with development of postvaccination protective antibodies were explored using univariate analysis. Results: The cohort included 281 children (270 [96%] liver, 9 [3%] kidney, 2 [1%] liver-kidney recipients) from 18 centers. The median time from transplant to enrollment was 6.3 years (IQR, 3.4-11.1 years). The median age at first posttransplant vaccine was 8.9 years (IQR, 4.7-13.8 years). A total of 202 of 275 (73%) children were receiving low-level monotherapy immunosuppression at the time of vaccination. The majority of children developed protective antibodies following vaccination (107 of 149 [72%] varicella, 130 of 152 [86%] measles, 100 of 120 [83%] mumps, and 124 of 125 [99%] rubella). One year post vaccination, the majority of children who initially mounted protective antibodies maintained this protection (34 of 44 [77%] varicella, 45 of 49 [92%] measles, 35 of 42 [83%] mumps, 51 of 54 [94%] rubella). Five children developed clinical varicella, all of which resolved within 1 week. There were no cases of measles or rubella and no episodes of graft rejection within 1 month of vaccination. There was no association between antibody response and immunosuppression level at the time of vaccination. Conclusions and Relevance: The findings suggest that live vaccinations may be safe and immunogenic after solid organ transplant in select pediatric recipients and can offer protection against circulating measles, mumps, and varicella.

OPTN/SRTR 2021 Annual Data Report: Liver.

In 2021, liver transplant volume continued to grow, with a record 9,234 transplants performed in the United States, 8,665 (93.8%) from deceased donors and 569 (6.2%) from living donors. There were 8,733 (94.6%) adult and 501 (5.4%) pediatric liver transplant recipients. An increase in the number of deceased donor livers corresponded to an increase in the overall transplant rate and shorter waiting times, although still 10.0% of livers that were recovered were not transplanted. Alcohol-associated liver disease was the leading indication for both waitlist registration and liver transplant in adults, outpacing nonalcoholic steatohepatitis, while biliary atresia remained the leading indication for children. Related to allocation policy changes implemented in 2019, the proportion of liver transplants performed for hepatocellular carcinoma has decreased. Among adult candidates listed for liver transplant in 2020, 37.7% received a deceased donor liver transplant within 3 months, 43.8% within 6 months, and 53.3% within 1 year. Pretransplant mortality improved for children following implementation of acuity circle-based distribution. Short-term graft and patient survival outcomes up to 1 year worsened for adult deceased and living donor liver transplant recipients, which is a reversal of previous trends and coincided with the onset of the COVID-19 pandemic in early 2020. Longer-term outcomes among adult deceased donor liver transplant recipients were unaffected, with overall posttransplant mortality rates of 13.3% at 3 years, 18.6% at 5 years, and 35.9% at 10 years. Pretransplant mortality improved for children following implementation of acuity circle-based distribution and prioritization of pediatric donors to pediatric recipients in 2020. Pediatric living donor recipients had superior graft and patient survival outcomes compared with deceased donor recipients at all time points.

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.

Health Care Resource Utilization by Patients with Alagille Syndrome.

OBJECTIVE: To assess and characterize health care resource utilization (HRU) in children with the rare, genetic, multisystem disorder, Alagille syndrome. STUDY DESIGN: This retrospective analysis reviewed commercially insured and Medicaid-insured claims from October 1, 2015 to December 31, 2019 to assess HRU in patients with Alagille syndrome. As there is no specific International Classification ofDiseases-10 code for Alagille syndrome, patients were identified using the following algorithm: ≥1 claim with diagnosis code Q44.7 (other congenital malformations of the liver); <18 years of age, with no history of biliary atresia (International Classification ofDiseases-10 code: Q44.2); and ≥6 months of insurance eligibility prior to diagnosis. HRU was summarized per patient per year over all available claims postdiagnosis. RESULTS: A total of 171 commercially insured and 215 Medicaid-insured patients with Alagille syndrome were available for analysis. Annually, commercially insured and Medicaid-insured patients averaged 31 medical visits (range, 1.5-237) and 48 medical visits (range, 0.7-690), respectively. The most common visits were outpatient with the majority encompassing lab/imaging and primary care visits (commercially insured: 21 [range, 0.0-183]; Medicaid-insured: 26 [range, 0.0-609]). Inpatient visits were the highest driver of costs in both the commercial and Medicaid populations. CONCLUSIONS: Patients with Alagille syndrome have a substantial HRU burden driven largely by numerous outpatient visits and costly inpatient stays. Given the complexity and variability of Alagille syndrome presentation, patients may benefit from multidisciplinary and subspecialized care.

Caregivers' and providers' perspectives of social and medical care after pediatric liver transplant: Results from the multicenter SOCIAL-Tx study.

Disparities exist in pediatric liver transplant (LT). We characterized barriers and facilitators to providing transplant and social care within pediatric LT clinics. This was a multicenter qualitative study. We oversampled caregivers reporting household financial strain, material economic hardship, or demonstrating poor health literacy. We also enrolled transplant team members. We conducted semistructured interviews with participants. Caregiver interviews focused on challenges addressing transplant and household needs. Transplant provider interviews focused on barriers and facilitators to providing social care within transplant teams. Interviews were recorded, transcribed, and coded according to the Capability, Opportunity, Motivation-Behavior model. We interviewed 27 caregivers and 27 transplant team members. Fifty-two percent of caregivers reported a household income <$60,000, and 62% reported financial resource strain. Caregivers reported experiencing (1) high financial burdens after LT, (2) added caregiving labor that compounds the financial burden, (3) dependency on their social network's generosity for financial and logistical support, and (4) additional support being limited to the perioperative period. Transplant providers reported (1) relying on the pretransplant psychosocial assessment for identifying social risks, (2) discomfort initiating social risk discussions in the post-transplant period, (3) reliance on social workers to address new social risks, and (4) social workers feeling overburdened by quantity and quality of the social work referrals. We identified barriers to providing effective social care in pediatric LT, primarily a lack of comfort in assessing and addressing new social risks in the post-transplant period. Addressing these barriers should enhance social care delivery and improve outcomes for these children.

Outcomes after liver transplantation in MPV17 deficiency (Navajo neurohepatopathy): A single-center case series.

BACKGROUND: MPV17-related mitochondrial DNA maintenance defect (MPV17 deficiency) is a rare, autosomal recessive mitochondrial DNA depletion syndrome with a high mortality rate in infancy and early childhood due to progression to liver failure. Liver transplantation for children with MPV17 deficiency has been considered controversial due to uncertainty about the potential progression of extrahepatic manifestations following liver transplantation. METHODS: We describe our institution's experience for two infants diagnosed with infantile MPV17 deficiency who presented in acute on chronic liver failure, but with normal development and normal neurological status who successfully underwent liver transplantation. RESULTS: Both patients underwent successful liver transplantation with normal development and neurological status at 3 years and 16 months post-transplant, respectively. CONCLUSIONS: In this rare disease population, we describe two infants with MPV17 deficiency who underwent liver transplantation for acute on chronic liver failure who continue to have normal development, without progression of neurological disease. MPV17 deficiency should not be considered a contraindication to liver transplantation.

A review of racial, socioeconomic, and geographic disparities in pediatric liver transplantation.

Equity is a core principle in both pediatrics and solid organ transplantation. Health inequities, specifically across race, socioeconomic position, or geography, reflect a moral failure. Ethical principles of prudential life span, maximin principle, and fair innings argue for allocation priority to children related to the number of life years gained, equal access to transplant, and equal opportunity for ideal posttransplant outcomes. Iterative policy changes have aimed to narrow these disparities to achieve pediatric transplant equity. These policy changes have focused on modifying pediatric priority for organ allocation to eliminate mortality on the pediatric transplant waiting list. Yet disparities remain in pediatric liver transplantation at all time points: from access to referral for transplantation, likelihood of living donor transplantation, use of exception narratives, waitlist mortality, and inequitable posttransplant outcomes. Black children are less likely to be petitioned for exception scores, have higher waitlist mortality, are less likely to be the recipient of a living donor transplant, and have worse posttransplant outcomes compared with White children. Children living in the most socioeconomically deprived neighborhoods have worse posttransplant outcomes. Children living farther from a transplant center have higher waitlist mortality. Herein we review the current knowledge of these racial and ethnic, socioeconomic, and geographic disparities for these children. To achieve equity, stakeholder engagement is required at all levels from providers and health delivery systems, learning networks, institutions, and society. Future initiatives must be swift, bold, and effective with the tripartite mission to inform policy changes, improve health care delivery, and optimize resource allocation to provide equitable transplant access, waitlist survival, and posttransplant outcomes for all children.

The Impact of Severe Acute Respiratory Syndrome Coronavirus Type 2 on Children With Liver Diseases: A Joint European Society for Pediatric Gastroenterology, Hepatology and Nutrition and Society of Pediatric Liver Transplantation Position Paper.

ABSTRACT: Children are seldom affected by severe forms of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV2) infection; however, the impact of comorbidities in the clinical presentation and outcome of SARS-CoV2 in children is poorly characterized including that of chronic liver disease (CLD) and those taking immunosuppressive medications for autoimmune liver disease or following liver transplantation (LT). Although not the main target organ, a spectrum of liver involvement has been described in children infected with SARS-CoV2 and those presenting with Multisystem Inflammatory Syndrome in Children (MIS-C). The Hepatology Committee of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and the Society of Pediatric Liver Transplantation (SPLIT) present an evidence-based position paper on liver involvement in children with SARS-CoV2 infection and its impact on those with CLD as well as LT recipients. All children may exhibit acute liver injury from SARS-CoV2 infection, and those with CLD and may experience hepatic decompensation. Preventative and therapeutic measures are discussed.

Severe Acute Respiratory Syndrome Coronavirus-2 Infection in Children With Liver Transplant and Native Liver Disease: An International Observational Registry Study.

OBJECTIVE: Increased mortality risk because of severe acute respiratory syndrome coronavirus-2 (SARS-CoV2) infection in adults with native liver disease (LD) and liver transplant (LT) is associated with advanced age and comorbid conditions. We aim to report outcomes for children with LD and LT enrolled in the NASPGHAN/SPLIT SARS-CoV2 registry. METHODS: In this multicenter observational cohort study, we collected data from 91 patients <21 years (LD 44, LT 47) with laboratory-confirmed SARS-CoV2 infection between April 21 and September 17, 2020. RESULTS: Patients with LD were more likely to require admission (70% vs 43% LT, P = 0.007) and pediatric intensive care unit (PICU) management (32% vs 4% LT, P = 0.001). Seven LD patients required mechanical ventilation (MV) and 2 patients died; no patients in the LT cohort died or required MV. Four LD patients presented in pediatric acute liver failure (PALF), 2 with concurrent multisystem inflammatory syndrome in children (MIS-C); all recovered without LT. Two LD patients had MIS-C alone and 1 patient died. Bivariable logistic-regression analysis found that patients with nonalcoholic fatty LD (NAFLD) (odds ratio [OR] 5.6, P = 0.02) and LD (OR 6.1, P = 0.01, vs LT) had higher odds of severe disease (PICU, vasopressor support, MV, renal replacement therapy or death). CONCLUSIONS: Although not directly comparable, LT recipients had lower odds of severe SARS-CoV2 infection (vs LD), despite immunosuppression burden. NAFLD patients reported to the registry had higher odds of severe SARS-CoV2 disease. Future controlled studies are needed to evaluate effective treatments and further stratify LD and LT patients with SARS-CoV2 infection.

Outcomes in Patients with Alagille Syndrome and Complex Pulmonary Artery Disease.

OBJECTIVE: To assess outcomes in a large cohort of patients with Alagille syndrome (ALGS) who underwent pulmonary artery reconstruction surgery for complex pulmonary artery disease. STUDY DESIGN: Patients with ALGS who underwent pulmonary artery reconstruction surgery at Lucile Packard Children's Hospital Stanford were reviewed. Patients were examined as an overall cohort and based on the primary cardiovascular diagnosis: severe isolated branch pulmonary artery stenosis, tetralogy of Fallot (TOF) without major aortopulmonary collateral arteries (MAPCAs), or TOF with MAPCAs. RESULTS: Fifty-one patients with ALGS underwent pulmonary artery surgery at our center, including 22 with severe branch pulmonary artery stenosis, 9 with TOF without MAPCAs, and 20 with TOF and MAPCAs. Forty-one patients (80%) achieved a complete repair. Five of the patients with TOF with MAPCAs (25%) underwent complete repair at the first surgery, compared with 8 (89%) with TOF without MAPCAs and 19 (86%) with isolated branch pulmonary artery stenosis. At a median follow-up of 1.7 years after the first surgery, 39 patients (76%) were alive, 36 with a complete repair and a median pulmonary artery:aortic systolic pressure of 0.38. Nine patients (18%), including 8 with isolated branch pulmonary artery stenosis, underwent liver transplantation. CONCLUSIONS: Most patients with ALGS and complex pulmonary artery disease can undergo complete repair with low postoperative right ventricular pressure. Patients with TOF/MAPCAs had the worst outcomes, with higher mortality and more frequent pulmonary artery interventions compared with patients with TOF without MAPCAs or isolated branch pulmonary artery stenosis. Complex pulmonary artery disease is not a contraindication to liver transplantation in patients with ALGS.

Decreased Incidence of Hepatic Artery Thrombosis in Pediatric Liver Transplantation Using Technical Variant Grafts: Report of the Society of Pediatric Liver Transplantation Experience.

OBJECTIVE: To evaluate risk factors for hepatic artery thrombosis (HAT) and examine the long-term outcomes of graft and patient survival after HAT in pediatric recipients of liver transplantation. STUDY DESIGN: Using multicenter data from the Society of Pediatric Liver Transplantation, Kaplan-Meier and Cox regression analyses were performed on first-time pediatric (aged <18 years) liver transplant recipients (n = 3801) in the US and Canada between 1995 and 2016. RESULTS: Of children undergoing their first liver transplantation, 7.4% developed HAT within the first 90 days of transplantation and, of those who were retransplanted, 20.7% developed recurrent HAT. Prolonged warm ischemia times increased the odds of developing HAT (OR, 1.11; P = .02). Adolescents aged 11-17 years (OR, 0.53; P = .03) and recipients with split, reduced, or living donor grafts had decreased odds of HAT (OR, 0.59; P < .001 compared with whole grafts). Fifty percent of children who developed HAT developed graft failure within the first 90 days of transplantation (adjusted hazard ratio, 11.87; 95% CI, 9.02-15.62) and had a significantly higher post-transplant mortality within the first 90 days after transplantation (adjusted hazard ratio, 6.18; 95% CI, 4.01-9.53). CONCLUSIONS: These data from an international registry demonstrate poorer long-term graft and patient survival in pediatric recipients whose post-transplant course is complicated by HAT. Notably, recipients of technical variant grafts had lower odds of HAT compared with whole liver grafts.