Outcomes after liver transplantation in accordance with ABO compatibility: A systematic review and meta-analysis

AIM To evaluate the differences in outcomes between ABOincompatible(ABO-I) liver transplantation(LT) and ABO-compatible(ABO-C) LT.METHODS A systematic review and meta-analysis were performed by searching eligible articles published before November 28, 2016 on MEDLINE(Pub Med), EMBASE, and Cochrane databases. The primary endpoints were graft survival, patient survival, and ABO-I-related complications. RESULTS Twenty-one retrospective observational studies with a total of 8247 patients were included in this metaanalysis. Pooled results of patient survival for ABO-I LT were comparable to those for ABO-C LT. However, ABO-I LT showed a poorer graft survival than ABO-C LT(1-year: OR = 0.66, 95%CI: 0.57-0.76, P < 0.001; 3-year: OR = 0.74, 95% CI 0.64-0.85, P < 0.001; 5-yearr: OR =0.75, 95%CI: 0.66-0.86, P < 0.001). Furthermore, ABO-I LT was associated with more incidences of antibody-mediated rejection(OR = 74.21, 95%CI: 16.32-337.45, P < 0.001), chronic rejection(OR =2.28, 95%CI: 1.00-5.22, P = 0.05), cytomegalovirus infection(OR = 2.64, 95%CI: 1.63-4.29, P < 0.001), overall biliary complication(OR = 1.52, 95%CI: 1.01-2.28, P = 0.04), and hepatic artery complication(OR = 4.17, 95%CI: 2.26-7.67, P < 0.001) than ABO-C LT. In subgroup analyses, ABO-I LT and ABO-C LT showed a comparable graft survival in pediatric patients and those using rituximab, and ABO-I LT showed an increased acute cellular rejection in cases involving deceased donor grafts.CONCLUSION Although patient survival in ABO-I LT was comparable to that in ABO-C LT, ABO-I LT was inferior to ABO-C LT in graft survival and several complications. Graft survival of ABO-I LT could be comparable to that of ABO-C LT in pediatric patients and those using rituximab.