ABO Incompatible Grafts Are Associated With Excellent Outcomes in Pediatric Liver Transplant Recipients: An Important Resource to Reduce Waitlist Mortality.

Background: Liver transplant (LT) waitlist mortality occurs in 10% of children; innovative strategies to expand access to LT can be lifesaving.

Methods: Outcomes of ABO incompatible (ABOi) LT performed between 1999 and 2023 at a high-volume center were compared to ABO compatible (ABOc) LT.

Results: 25 ABOi LT were performed among 270 LT; 72% were listed with status 1/1A/1B or a median pediatric end-stage liver disease/model for end-stage liver disease of 40 (IQR 32,41). Time on the waitlist for ABOi recipients was shorter (median 11 days [IQR 4,46]) compared to ABOc (113 days [IQR 39,252], p < 0.001). ABOi graft types were 64% technical variants (including 2 living donor grafts) and 36% whole; 52% received a duct-duct biliary anastomosis. There were no statistically significant differences in 1/5/10-year patient survival [ABOi: 87,87,87% vs. ABOc: 96,94,89%, p = 0.6] or graft survival [ABOi: 87,82,82% vs. ABOc: 92,86,80%, p = 0.9]. When compared to ABOc, there were no statistically significant differences in vascular complications, bile leaks, or acute T-cell-mediated rejection with ABOi LT. Biliary strictures were diagnosed in 43% of ABOi LT and more frequently than in ABOc (20%, p = 0.0495).

Conclusions: ABOi LT can offer children on the waitlist a survival advantage through shorter waiting time. ABOi LT can be performed safely with a low rate of vascular complications similar to ABOc LT.