Banff 2022 Liver Group Meeting report: Monitoring long-term allograft health.

The Banff Working Group on Liver Allograft Pathology met in September 2022. Participants included hepatologists, surgeons, pathologists, immunologists, and histocompatibility specialists. Presentations and discussions focused on the evaluation of long-term allograft health, including noninvasive and tissue monitoring, immunosuppression optimization, and long-term structural changes. Potential revision of the rejection classification scheme to better accommodate and communicate late T cell-mediated rejection patterns and related structural changes, such as nodular regenerative hyperplasia, were discussed. Improved stratification of long-term maintenance immunosuppression to match the heterogeneity of patient settings will be central to improving long-term patient survival. Such personalized therapeutics are in turn contingent on a better understanding and monitoring of allograft status within a rational decision-making approach, likely to be facilitated in implementation with emerging decision-support tools. Proposed revisions to rejection classification emerging from the meeting include the incorporation of interface hepatitis and fibrosis staging. These will be opened to online testing, modified accordingly, and subject to consensus discussion leading up to the next Banff conference.

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.

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.

Caregiver Perceptions of Social Risk Screening in Pediatric Liver Transplantation: From the Multicenter SOCIAL-Tx Study.

BACKGROUND: The social determinants of health contribute to adverse post-liver transplant outcomes. Identifying unmet social risks may enable transplant teams to improve long-term outcomes for at-risk children. However, providers may feel uncomfortable asking about household-level social risks in the posttransplant period because they might make their patients/families uncomfortable. METHODS: We conducted a mixed-methods analysis of caregiver participants (ie, parents/guardians of pediatric liver transplant recipients) in the Social and Contextual Impact on Children Undergoing Liver Transplantation study to assess their perceptions of provider-based social risk screening. Participants (N = 109) completed a 20-min social determinants of health questionnaire that included questions on the acceptability of being asked intimate social risk questions. A subset of participants (N = 37) engaged in an in-depth qualitative interview to share their perceptions of social risk screening. RESULTS: Of 109 participants across 9 US transplant centers, 60% reported financial strain and 30% reported at least 1 material economic hardship (eg, food insecurity, housing instability). Overall, 65% of respondents reported it very or somewhat appropriate and 25% reported being neutral to being screened for social risks in a liver transplant setting. In qualitative analyses, participants reported trust in the providers and a clear understanding of the intention of the screening as prerequisites for liver transplant teams to perform social risk screening. CONCLUSIONS: Only a small minority of caregivers found social risk screening unacceptable. Pediatric liver transplant programs should implement routine social risk screening and prioritize the patient and family voices when establishing a screening program to ensure successful implementation.

Ambient air pollution is associated with graft failure/death in pediatric liver transplant recipients.

Children exposed to disproportionately higher levels of air pollution experience worse health outcomes. In this population-based, observational registry study, we examine the association between air pollution and graft failure/death in children following liver transplantation (LT) in the US. We modeled the associations between air pollution (PM2.5) levels localized to the patient's ZIP code at the time of transplant and graft failure or death using Cox proportional-hazards models in pediatric LT recipients aged <19 years in the US from 2005-2015. In univariable analysis, high neighborhood PM2.5 was associated with a 56% increased hazard of graft failure/death (HR: 1.56; 95% CI: 1.32, 1.83; P < .001). In multivariable analysis, high neighborhood PM2.5 was associated with a 54% increased risk of graft failure/death (HR: 1.54; 95% CI: 1.29, 1.83; P < .001) after adjusting for race as a proxy for racism, insurance status, rurality, and neighborhood socioeconomic deprivation. Children living in high air pollution neighborhoods have an increased risk of graft failure and death posttransplant, even after controlling for sociodemographic variables. Our findings add further evidence that air pollution contributes to adverse health outcomes for children posttransplant and lay the groundwork for future studies to evaluate underlying mechanisms linking PM2.5 to adverse LT outcomes.

Immunosuppression-Free Life after Pediatric Liver Transplant: A Case-Control Study from the Society of Pediatric Liver Transplant (SPLIT) Registry.

OBJECTIVE: To compare long-term outcomes of pediatric liver transplant (LT) recipients off immunosuppression (IS) with matched controls on IS using data from the Society of Pediatric Liver Transplant (SPLIT) registry. STUDY DESIGN: This was a retrospective case-control study. SPLIT participants <18 years of age, ≥4 years after isolated LT, and off IS for ≥1 year (cases) were age- and sex-matched 1:2 to patients with the same primary diagnosis and post-LT follow-up duration (controls). Primary outcomes included retransplantation, allograft rejection, IS comorbidities, and prevalence of SPLIT-derived composite ideal outcome (c-IO) achieved at the end of the follow-up period. Differences were compared using multiple linear regression for continuous outcomes and logistic regression for dichotomous data. RESULTS: The study cohort was composed of 33 cases (42.4% male, 60.6% biliary atresia, median age at LT of 0.7 [P25, P75, 0.5, 1.6] years, median IS withdrawal time of 9 [P25, P75, 6, 12] years after LT) and 66 age- and sex-matched controls. No cases required retransplantation. Cases and controls had similar growth parameters, laboratory values, calculated glomerular filtration rates, rates of post-transplant lymphoproliferative disease, graft rejection, and attainment of c-IO. CONCLUSIONS: No differences in allograft rejection rates, IS complications, or c-IO prevalence were seen between SPLIT patients off IS and age- and sex-matched controls remaining on IS. Discontinuation of IS most commonly occurred in the context of rigorously designed IS withdrawal trials. The available sample size was small, affecting generalizability to the broader pediatric LT population.

Balancing immunosuppression in pediatric liver transplantation: Playing the long game.

The overarching goal in the care of pediatric liver transplant recipients is to optimize allograft and patient health. Balancing immunosuppression to maintain allograft health while avoiding medication side effects is essential for long-term survival and optimal quality of life in pediatric liver transplant recipients. Utilizing precision medicine to personalize immunosuppression, which includes minimization and withdrawal, is core to this effort. The unique anatomy and physiology of the liver make it more tolerant to immune-mediated injury and a more favorable organ for immunosuppression minimization and withdrawal. However, several challenges exist. Standard biochemical values and histologic features may not reliably predict allograft health after a reduction in immunosuppression. Additionally, biochemical values alone do not reliably identify which patients can successfully develop operational tolerance, as there may be occult allograft injury despite normal liver enzymes. Finally, the durability of tolerance after successful reduction in immunosuppression remains uncertain over time. Innovative tools show promise in circumventing these challenges, but more research is needed to determine actual clinical utility. While immunosuppression-free transplant may not be a current reality for most pediatric liver transplant recipients, strategies to safely minimize immunosuppression without compromising allograft health are within reach. Each liver allograft and recipient pair requires a different degree of immune modulation, and through a structured process of minimization and withdrawal, immunosuppression can indeed be tailored in a precise, personalized way to optimize outcomes. This review focuses on the progress that has been made to individualize immunosuppression in pediatric liver transplantation to ensure optimal allograft and recipient health.

Mapping children by ALT 4-5 years after liver transplant: Potential individual and population applications.

INTRODUCTION: Although clinicians repeatedly measure ALT to assess allograft health in children with liver transplants, they generally make decisions based on single values or qualitative trends without quantitative aggregation or synthesis. We therefore aimed to derive and test a holistic ALT metric for the 5th post-transplant year (Yr 4-5) that may better guide clinical decision-making and/or population comparisons. METHODS: We derived the "adjusted mean Yr 4-5 ALT" for children transplanted in 2005-2016 by averaging the median ALT from each month. Patients in quartiles (Q1-4) defined by the adjusted mean Yr 4-5 ALT were compared by clinical variables, Yr 5-8 outcomes, and tacrolimus standard deviation (MLVI). RESULTS: For 97 children [49 male; 77 deceased donors; median (IQR) age at LT 2.5 (0.8-11.7) years], the 25th, 50th, and 75th percentile thresholds for adjusted mean Yr 4-5 ALT were 19, 28, and 47 U/L, respectively. Age, donor type, LT indication, rejection history, and mean tacrolimus levels did not differ between quartiles (Q). Children in Q4 had more Yr 4-5 acute rejection episodes (p < .01), higher Yr 4-5 MLVI (p < .01), and more Yr 5-8 for-cause liver biopsies (p < .01) than those in Q1 + Q2. Children in Q3 also had higher Yr 4-5 MLVI than Q1 + Q2 (p = .047). Rates of chronic rejection and therapeutic liver-related procedures were higher in Q4 but the difference did not reach significance. CONCLUSION: An integrated ALT metric calculated utilizing all available ALT values correlates with MLVI and future for-cause biopsies. Further study of this novel ALT metric as a predictor of clinical outcomes and descriptor of populations is warranted.

Factors associated with thrombotic and hemorrhagic complications in pediatric liver transplant: A multi-center analysis from the Starzl Network for Excellence in Pediatric Transplantation.

BACKGROUND: Survival after pediatric liver transplantation (PLT) is negatively impacted by thrombotic and hemorrhagic complications. Limited data exists regarding factors associated with these complications and utilization of anticoagulation. METHODS: Retrospective review of donor, recipient variables and outcomes from four centers participating in the Starzl Network for Excellence in Pediatric Transplantation. RESULTS: 76 PLT included 39 (51%) technical variant transplants, with mean follow-up 628 ± 193.6 days. Median age/weight at transplant were 59.3 ± 53.8 months and 19.6 ± 17.2 kg. Seven (9.2%) transplants experienced intraoperative hepatic artery thrombosis (iHAT), all successfully corrected. Four HAT recurred postoperatively on POD 1,7,8 and 616. All three portal vein thromboses (PVT) occurred on POD1. Anticoagulation protocols were initiated intraoperatively in 50 and postoperatively in 66 and were active for all thrombotic and hemorrhagic events. Two patients were re-transplanted for HAT. Two patients died without having thrombotic or hemorrhagic complications. iHAT and post-operative HAT were associated with lower hepatic arterial flows. iHAT was associated with donor variant anatomy, reduced allografts and intraoperative blood loss. Intraoperative ultrasound could not predict post-operative HAT nor PVT. Surgeon pre-operative concern regarding the native portal vein correlated with postoperative PVT. Lower hepatic arterial and portal flows, higher estimated blood losses, higher prothrombin time and use of arterial interposition grafts were associated with postoperative hemorrhagic complications. CONCLUSIONS: Thrombotic and hemorrhagic complications after pediatric liver transplant remain rare but significant events. Their occurrence can be predicted with pre-operative assessment of donor and recipient vascular anatomy and direct flow measurement but may not be predicted with ultrasound evaluation nor prevented with anticoagulation.

Immunosuppression after pediatric liver transplant: The parents' perspective.

BACKGROUND: For children with liver transplants (LT), achieving an "ideal outcome" is a balancing act: too little immunosuppression begets graft injury; too much begets systemic complications. We aimed to delineate the parental perspective on this tightrope. METHODS: Parents of children with LT completed an internet-based survey about their child's immunosuppression. RESULTS: Children of respondents (n = 82) were a median 4 years from primary LT (range 0-22); 73% were on immunosuppression monotherapy. Parents' top concerns were related to immunosuppression complications; 46% were more concerned about immunosuppression complications than rejection; only 17% were more concerned about rejection than immunosuppression complications. Among parents of children on immunosuppression monotherapy, 29% still worried more about immunosuppression complications than rejection, 48% expressed equal concern for both. Time since LT (0-4 vs. >4 years) was not associated with concern level for rejection or immunosuppression complications. Caregivers were significantly more certain that their child's immunosuppression regimen was correct to prevent rejection than to mitigate complications (p < .005). CONCLUSION: Caregivers of children with LTs reported higher levels of concern and uncertainty about immunosuppression complications than rejection risk. Understanding parent and patient perspectives on IS, and incorporating them into immunosuppression counseling and decision-making, is critical to achieving truly "ideal" long-term outcomes.

Next-generation pathology detection of T cell-antigen-presenting cell immune synapses in human liver allografts.

BACKGROUND AND AIMS: In otherwise near-normal appearing biopsies by routine light microscopy, next-generation pathology (NGP) detected close pairings (immune pairs; iPAIRs) between lymphocytes and antigen-presenting cells (APCs) that predicted immunosuppression weaning failure in pediatric liver transplant (LTx) recipients (Immunosuppression Withdrawal for Stable Pediatric Liver Transplant Recipients [iWITH], NCT01638559). We hypothesized that NGP-detected iPAIRs enrich for true immune synapses, as determined by nuclear shape metrics, intercellular distances, and supramolecular activation complex (SMAC) formation. APPROACH AND RESULTS: Intralobular iPAIRs (CD45 high lymphocyte-major histocompatibility complex II + APC pairs; n = 1167, training set) were identified at low resolution from multiplex immunohistochemistry-stained liver biopsy slides from several multicenter LTx immunosuppression titration clinical trials (iWITH; NCT02474199 (Donor Alloantigen Reactive Tregs (darTregs) for Calcineurin Inhibitor (CNI) Reduction (ARTEMIS); Prospective Longitudinal Study of iWITH Screen Failures Secondary to Histopathology). After excluding complex multicellular aggregates, high-resolution imaging was used to examine immune synapse formation ( n = 998). By enriching for close intranuclear lymphocyte-APC distance (mean: 0.713 µm) and lymphocyte nuclear flattening (mean ferret diameter: 2.1), SMAC formation was detected in 29% of iPAIR-engaged versus 9.5% of unpaired lymphocytes. Integration of these morphometrics enhanced NGP detection of immune synapses (ai-iSYN). Using iWITH preweaning biopsies from eligible patients ( n = 53; 18 tolerant, 35 nontolerant; testing set), ai-iSYN accurately predicted (87.3% accuracy vs. 81.4% for iPAIRs; 100% sensitivity, 75% specificity) immunosuppression weaning failure. This confirmed the presence and importance of intralobular immune synapse formation in liver allografts. Stratification of biopsy mRNA expression data by immune synapse quantity yielded the top 20 genes involved in T cell activation and immune synapse formation and stability. CONCLUSIONS: NGP-detected immune synapses (subpathological rejection) in LTx patients prior to immunosuppression reduction suggests that NGP-detected (allo)immune activity usefulness for titration of immunosuppressive therapy in various settings.

Health Care Transition for Adolescents and Young Adults With Pediatric-Onset Liver Disease and Transplantation: A Position Paper by the North American Society of Pediatric Gastroenterology, Hepatology, and Nutrition.

Advances in medical therapies and liver transplantation have resulted in a greater number of pediatric patients reaching young adulthood. However, there is an increased risk for medical complications and morbidity surrounding transfer from pediatric to adult hepatology and transplant services. Health care transition (HCT) is the process of moving from a child/family-centered model of care to an adult or patient-centered model of health care. Successful HCT requires a partnership between pediatric and adult providers across all disciplines resulting in a transition process that does not end at the time of transfer but continues throughout early adulthood. Joint consensus guidelines in collaboration with the American Society of Transplantation are presented to facilitate the adoption of a structured, multidisciplinary approach to transition planning utilizing The Six Core Elements of Health Care Transition TM for use by both pediatric and adult specialists. This paper provides guidance and seeks support for the implementation of an HCT program which spans across both pediatric and adult hepatology and transplant centers.

Increase in Rate of Hospitalizations for Pediatric Intentional Acetaminophen Ingestion at a Single Center During the COVID-19 Pandemic.

OBJECTIVES: Social disruption due to COVID-19 has detrimentally affected American adolescents' emotional well-being. Within our system, pediatric acetaminophen ingestions increased in 2020, compared with previous years. We sought to evaluate the rate of hospitalizations for acetaminophen self-harm ingestions and self-harm of adolescents during the COVID-19 pandemic. STUDY DESIGN: We identified patients (aged 0-23) from billing data with diagnosis of acetaminophen ingestion with self-harm intent (ICD-10 code T391X2A), from a multicenter urban, quaternary health care system. We performed retrospective chart review from 2016 to 2020 and performed statistics using a generalized estimating equation (GEE) logistic regression model. RESULTS: From 2016 to 2020, there were 25 790 discharges of adolescents with 65 acetaminophen self-harm ingestion and 148 self-harm discharges. Of the 65 acetaminophen patients, 75% identified as female and 54% identified as non-white; 71% with Medicaid insurance. The proportion of acetaminophen ingestion and self-harm admissions increased from 0.13% in 2016 to 0.46% by 2020 and 0.42% in 2016 to 0.73% by 2020, respectively. The odds of acetaminophen ingestion admission increased by 28% each additional year (odds ratio = 1.28; 95% confidence interval: 1.08, 1.53; P = .006). There was not enough evidence to conclude that the log-odds of a self-harm ingestion were linearly related to time (P = .06). CONCLUSIONS: Acetaminophen ingestion for self-harm has significantly increased, while overall self-harm has increased to a lesser, nonsignificant degree. Primarily females of color and those with Medicaid insurance are affected. It is important to note this growing, disturbing trend, and to continue to screen for depression in our adolescent community and ensure access to mental health resources.

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.

Caregiver perspectives on the everyday medical and social needs of long-term pediatric liver transplant patients.

Using in-depth interviews, we sought to characterize the everyday medical and social needs of pediatric liver transplant caregivers to inform the future design of solutions to improve care processes. Participants (parents/caregivers of pediatric liver transplant recipients) completed a survey (assessing socioeconomic status, economic hardship, health literacy, and social isolation). We then asked participants to undergo a 60-min virtual, semistructured qualitative interview to understand the everyday medical and social needs of the caregiver and their household. We intentionally oversampled caregivers who reported a social or economic hardship on the survey. Transcripts were analyzed using thematic analysis and organized around the Capability, Opportunity, Motivation-Behavior model. A total of 18 caregivers participated. Of the participants, 50% reported some form of financial strain, and about half had less than 4 years of college education. Caregivers had high motivation and capability in executing transplant-related tasks but identified several opportunities for improving care. Caregivers perceived the health system to lack capability in identifying and intervening on specific family social needs. Caregiver interviews revealed multiple areas in which family supports could be strengthened, including (1) managing indirect costs of prolonged hospitalizations (e.g., food, parking), (2) communicating with employers to support families' needs, (3) coordinating care across hospital departments, and (4) clarifying care team roles in helping families reduce both medical and social barriers. This study highlights the caregiver perspective on barriers and facilitators to posttransplant care. Future work should identify whether these themes are present across transplant centers. Caregiver perspectives should help inform future interventions aimed at improving long-term outcomes for children after liver transplantation.

Association of Primary Care Shortage Areas with Adverse Outcomes after Pediatric Liver Transplant.

OBJECTIVE: To characterize associations between living in primary care shortage areas and graft failure/death for children after liver transplantation. STUDY DESIGN: This was an observational study of all pediatric patients (aged <19 years) who received a liver transplant between January 1, 2005, and December 31, 2015 in the US, with follow-up through January 2019 (N = 5964). One hundred ninety-five patients whose home ZIP code could not be matched to primary care shortage area status were excluded. The primary outcome was a composite endpoint of graft failure or death. We used Cox proportional hazards to model the associations between health professional shortage area (HPSA) and graft failure/death. RESULTS: Children living in HPSAs had lower estimated graft survival rates at 10 years compared with those not in HPSAs (76% vs 80%; P < .001). In univariable analysis, residence in an HPSA was associated with a 22% higher hazard of graft failure/death than non-residence in an HPSA (hazard ratio [HR], 1.22; 95% CI, 1.09-1.36; P < .001). Black children from HPSAs had a 67% higher hazard of graft failure/death compared with those not in HPSAs (HR, 1.67; 95% CI, 1.29 to 2.16; P = .006); the effect of HPSA status was less pronounced for White children (HR, 1.11; 95% CI, 0.98-1.27; P = .10). CONCLUSIONS: Children living in primary care shortage areas are at increased risk of graft failure and death after liver transplant, and this risk is particularly salient for Black children. Future work to understand how living in these regions contributes to adverse outcomes may enable teams to mitigate this risk for all children with chronic illness.

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.

Graft Fibrosis Over 10 to 15 Years in Pediatric Liver Transplant Recipients: Multicenter Study of Paired, Longitudinal Surveillance Biopsies.

Previous single-center, cross-sectional studies have reported a steep increase in the prevalence and severity of fibrosis through 10 to 15 years after pediatric liver transplantation. We report a multicenter study of paired surveillance biopsies in a contemporary cohort. Children who underwent liver transplant when younger than 6 years old and had paired surveillance liver biopsies were enrolled (n = 78, 35% girls, median 1.2 years old at transplant). A central pathologist graded inflammation, assessed rejection activity index, and staged fibrosis in the portal, sinusoidal, and perivenular compartments, allowing for calculation of the Liver Allograft Fibrosis Score (LAFSc). Analysis of variance tested associations between fibrosis progression and clinical parameters. The first biopsy, at a median 8.2 years (interquartile range, 5.9-11.6 years) after transplantation, showed absent to mild fibrosis (LAFSc 0-2) in 29%, moderate (LAFSc 3-5) in 56%, and severe (LAFSc 6-7) in 14% of patients. The second biopsy, at a median 4.7 years (IQR, 4.3-5.1 years) later, showed fibrosis progression (LAFSc increased by ≥3) in 10 (13%) and regression (LAFSc decreased by ≥3) in 4 (5%) patients. After adjusting for baseline LAFSc, younger age at transplant was the only risk factor for fibrosis progression. Although fibrosis prevalence and severity 6 to 12 years after transplant was similar to previous reports, fibrosis trajectory during the next 4 to 5 years was stable. Our data may be reassuring for children with consistently normal liver tests. A comprehensive understanding of factors determining allograft health during the very long term is essential to optimizing allograft and patient health.