Exchange living donor liver transplantation to overcome ABO incompatibility in adult patients.

ABO incompatibility is the most common cause of donor rejection during the initial screening of adult patients with end-stage liver disease for living donor liver transplantation (LDLT). A paired donor exchange program was initiated to cope with this problem without ABO-incompatible LDLT. We present our results from the first 6 years of this exchange adult LDLT program. Between July 2003 and June 2009, 1351 adult LDLT procedures, including 16 donor exchanges and 7 ABO-incompatible LDLT procedures, were performed at our institution. Initial donor-recipient ABO incompatibilities included 6 A to B incompatibilities, 6 B to A incompatibilities, 1 A to O incompatibility, 1 A+O (dual graft) to B incompatibility, 1 O to AB incompatibility, and 1 O to A incompatibility. Fourteen matches (87.5%) were ABO-incompatible, but 2 (12.5%) were initially ABO-compatible. All ABO-incompatible donors were directly related to their recipients, but 2 compatible donors were each undirected and unrelated directed. After donor reassignment through paired exchange (n = 7) or domino pairing (n = 1), the donor-recipient ABO status changed to A to A in 6, B to B in 6, O to O in 1, A to AB in 1, A+O to A in 1, and O to B in 1, and this made all matches ABO-identical (n = 13) or ABO-compatible (n = 3). Two pairs of LDLT operations were performed simultaneously on an elective basis in 12 and on an emergency basis in 4. All donors recovered uneventfully. Fifteen of the 16 recipients survived, but 1 died after 54 days. In conclusion, an exchange donor program for adult LDLT appears to be a feasible modality for overcoming donor-recipient ABO incompatibility.