Hsu, Evelyn

ABSTRACT Background The Society of Pediatric Liver Transplantation (SPLIT) has undergone tremendous growth with > 45 sites contributing data focusing on improving outcomes in pediatric liver transplantation (LT). We report and compare outcomes from the SPLIT Registry. Methods Patients < 18 years with first‐time LT only enrolled into the SPLIT Registry between 2011 and 2023 were included. Data was stratified into eras from the last published registry update (era 1: 2011–2018, era 2: 2018–2023). Results Three thousand five hundred four participants from 47 centers were included (era 1: n = 2159; era 2: n = 1345). Age distribution differed with more children < 1 year. of age at LT in era 2 (era 1: 29% vs. era 2: 33%, p = 0.01). Indications for LT were similar, with biliary atresia (38.8%) and metabolic disease (16.0%) being most common. Exception point use was higher in era 2 (era 1: 45% vs. era 2: 56%, p < 0.001). No difference in graft type (deceased: 81% era 1 vs. 78% era 2, p = 0.78), patient survival at 90 days (era 1: 98.7% vs. era 2: 98.3%), 1 year (era 1: 97.2 vs. era 2: 96.8%), or 3 years (era 1: 95.3% vs. era 2: 95.2%) was noted. Rate of hepatic artery thrombosis was lower in era 2 (era 1: 7% vs. era 2: 5%, p = 0.02). Conclusions Trends in pediatric LT within SPLIT note similar LT indications and graft type, higher utilization of exception points, and lower HAT rates despite transplanting more children < 10 kg. This data underscores the evolution of pediatric LT toward higher survivability and overall patient outcomes.

AbstractATP6AP1‐CDG is an X‐linked disorder typically characterized by hepatopathy, immunodeficiency, and an abnormal type II transferrin glycosylation pattern. Here, we present 11 new patients and clinical updates with biochemical characterization on one previously reported patient. We also document intrafamilial phenotypic variability and atypical presentations, expanding the symptomatology of ATP6AP1‐CDG to include dystonia, hepatocellular carcinoma, and lysosomal abnormalities on hepatic histology. Three of our subjects received successful liver transplantation. We performed N‐glycan profiling of total and fractionated plasma proteins for six patients and show associations with varying phenotypes, demonstrating potential diagnostic and prognostic value of fractionated N‐glycan profiles. The aberrant N‐linked glycosylation in purified transferrin and remaining plasma glycoprotein fractions normalized in one patient post hepatic transplant, while the increases of Man4GlcNAc2 and Man5GlcNAc2 in purified immunoglobulins persisted. Interestingly, in the single patient with isolated immune deficiency phenotype, elevated high‐mannose glycans were detected on purified immunoglobulins without glycosylation abnormalities on transferrin or the remaining plasma glycoprotein fractions. Given the diverse and often tissue specific clinical presentations and the need of clinical management post hepatic transplant in ATP6AP1‐CDG patients, these results demonstrate that fractionated plasma N‐glycan profiling could be a valuable tool in diagnosis and disease monitoring.

Background. In December 2018, United Network for Organ Sharing approved an allocation scheme based on recipients’ geographic distance from a deceased donor (acuity circles [ACs]). Previous analyses suggested that ACs would reduce waitlist mortality overall, but their impact on pediatric subgroups was not considered. Methods. We applied Scientific Registry of Transplant Recipients data from 2011 to 2016 toward the Liver Simulated Allocation Model to compare outcomes by age and illness severity for the United Network for Organ Sharing–approved AC and the existing donor service area–/region-based allocation schemes. Means from each allocation scheme were compared using matched-pairs t tests. Results. During a 3-year period, AC allocation is projected to decrease waitlist deaths in infants (39 versus 55; P < 0.001), children (32 versus 50; P < 0.001), and teenagers (15 versus 25; P < 0.001). AC allocation would increase the number of transplants in infants (707 versus 560; P < 0.001), children (677 versus 547; P < 0.001), and teenagers (404 versus 248; P < 0.001). AC allocation led to decreased median pediatric end-stage liver disease/model for end-stage liver disease at transplant for infants (29 versus 30; P = 0.01), children (26 versus 29; P < 0.001), and teenagers (26 versus 31; P < 0.001). Additionally, AC allocation would lead to fewer transplants in status 1B in children (97 versus 103; P = 0.006) but not infants or teenagers. With AC allocation, 77% of pediatric donor organs would be allocated to pediatric candidates, compared to only 46% in donor service area–/region-based allocation (P < 0.001). Conclusions. AC allocation will likely address disparities for pediatric liver transplant candidates and recipients by increasing transplants and decreasing waitlist mortality. It is more consistent with federally mandated requirements for organ allocation.