Outcomes of Highly Urgent ABO-Incompatible Living Donor Liver Transplantation in National Databases

BACKGROUND: Highly urgent adult living donor liver transplantation (HU-LDLT) is essential for patients with acute liver failure (ALF), acute-on-chronic liver failure (ACLF), and severe cirrhosis who are in life-threatening situations. The results of adult highly urgent ABO-incompatible (ABOi) living donor liver transplantation (LDLT) remain ambiguous when there is insufficient time to await a compatible organ. This study aimed to compare the results of adult ABOi HU-LDLT with those of adult ABO-compatible (ABOc) HU-LDLT utilizing data from the Korean Network for Organ Sharing (KONOS). METHODS: We conducted a retrospective study using KONOS data from 363 consecutive adult HU-LDLT patients between 2017 and 2021 in Korea. RESULTS: The incidence of ABOc-LDLTs and ABOi-LDLTs was 90.6% (n = 329) and 9.4% (n = 34), respectively. Hepatitis B virus infection and alcoholism are the main etiologies of adult HU-LDLT. The median waiting time was 1 day (range, 0-36 days) for ABOc LDLT patients and 3 days (range, 0-28 days) for ABOi LDLT patients. None of the patients developed antibody-mediated rejection during follow-up. The incidence of graft failure was 17.6% in ABOi LDLT patients and 7.6% in ABOc LDLT patients. However, the overall survival and graft survival rates in the ABOi LDLT patients were not different from those in the ABOc LDLT patients. ABOi LDLT was not associated with graft failure or death in multivariable analysis. CONCLUSION: The present study supports ABOi-LDLTs as a feasible and safe treatment for highly urgent patients.