The "ABO cross-transplantation problem" in liver transplantation in Korea.

ABO blood group matching policy between donor and recipients is a chief element of organ allocation. However, O blood group donors may donate to all other blood group recipients, and ABO cross-transplantation has led to excessively long delays for blood group O. To investigate the consequence of this problem, we analyzed the recipients/donor rates according to ABO blood groups and cross-transplantation rates among them. Data about deceased donors and liver transplants performed in Korea from January 2008 to September 2012 were reviewed. The proportion of recipient to donor in the O blood group was lower compared to non-O groups (0.61). The percentage of O blood group transplantations in the Korean Network for Organ Sharing (KONOS) status 2B was lower than non-O groups (13.6%). In the status 1 and 2A groups, 44.4% of O blood group donors were allocated to non-O transplantations. Also, 30.7% O blood group donors were allocated to non-O transplantations in the status 2B groups. In conclusion, the ABO cross-transplantation in blood group O donors has led to lower transplantation rates of blood group O in status 1, 2A, and especially, the 2B group. Therefore, the KONOS allocation system should be re-evaluated to address this problem.