Introduction: We evaluated the effects of donor age and graft type on survival outcomes after liver transplantation (LT) for biliary atresia (BA).

Method: We performed a retrospective analysis of children with BA <18y who underwent first isolated LT using United Network for Organ Sharing data (02/27/2002-09/30/2025). Multivariable Cox regression included donor age group, graft type, recipient age group, laboratory MELD/PELD score, portal vein thrombosis (PVT), intensive care unit (ICU) status, and cold ischemia time (CIT).

Results: A total of 3,686 children with BA (<2y: 2,788 [75.6%] vs ≥2y: 898 [24.4%]) underwent LT. The donor age/graft groups were: <18y deceased donor whole graft (DDWG): 1,742 (47.3%), <18y deceased donor technical variant (DDTV): 791 (21.5%), 18-39y DDWG: 33 (0.9%), 18-39y DDTV: 339 (9.2%), 18-39y living donor LT (LDLT): 589 (16.0%), ≥40y DDWG: 12 (0.3%), ≥40y DDTV: 47 (1.3%), and ≥40y LDLT: 133 (3.6%). LDLT groups had lower CIT . In multivariable Cox regression, 18-39y LDLT donors were associated with decreased risk of mortality (HR=0.57, 95%CI: 0.32-0.99, p=0.049), while ≥40y DDTV donors (HR=5.13, 95%CI: 2.73-9.65, p<0.001), PVT (HR=1.81, 95%CI: 1.14-2.89, p=0.01), ICU status (HR=1.70, 95%CI: 1.19-2.44, p=0.004), and increasing CIT (HR=1.03, 95%CI: 1.00-1.07, p=0.03) were associated with increased risk of mortality. In multivariable Cox regression, 18-39y LDLT donors (HR=0.51, 95%CI: 0.36-0.73, p<0.001) and recipients ≥2y (HR=0.71, 95%CI: 0.55-0.92, p=0.01) were associated with decreased risk of graft loss, while ≥40y DDTV donors (HR=3.91, 95%CI: 2.52-6.08, p<0.001, PVT (HR=1.41, 95%CI: 1.01-1.96, p=0.0045), and ICU status (HR=1.56, 95%CI: 1.22-1.99, p<0.001) were associated with increased risk of graft loss.

Conclusion: 18-39y LDLT had optimal survival outcomes for children with BA whereas ≥40y DDTV and CIT increased mortality risk. Further studies are needed to identify modifiable factors after procurement that can improve function in ≥40y DDTV grafts and those with prolonged CIT.