Use of "O" blood group liver donors for nonidentical recipients: does this represent a double penalty for "O" blood group candidates?

Candidates for liver transplantation with AB blood group remain on the waiting list for shorter times than candidates with 0 blood group. To investigate the reasons of this phenomenon, we analyzed data concerning deceased donors, liver transplant candidates, and liver first transplants performed in the United States during the period 2003 to 2004. The percentage of deceased donors with blood group 0 was higher than that of candidates on the waiting list with the identical blood group (P <.05). On the other hand, for blood groups A, B, and AB an opposite situation was observed: the percentages of deceased donors were significantly lower compared to those candidates with the identical blood group (A blood group, P <.05; B and AB blood groups, P <.001). When the number of grafts from deceased donors was compared with the number of those effectively transplanted, a negative difference for 0 blood group recipients was found (ie, transplanted livers < harvested livers) and a positive one for AB blood group (transplanted livers > harvested livers) were found. Since disease progression and causes of acute liver failure, including primary nonfunction and hepatic artery thrombosis leading to retransplantation were similar among the various blood groups, we concluded that the shorter waiting time for AB patients in the pre-MELD era was due to the use of compatible livers to the detriment of group 0 recipients.