Trading with the waiting-list: the justice of living donor list exchange.

In a Living Donor List Exchange program, the donor makes his kidney available for allocation to patients on the postmortal waiting-list and receives in exchange a postmortal kidney, usually an O-kidney, to be given to the recipient he favours. The program can be a solution for a candidate donor who is unable to donate directly or to participate in a paired kidney exchange because of blood group incompatibility or a positive cross-match. Each donation within an LDLE program makes an additional organ available for transplantation. But because most of the pairs making use of the program will be A/O incompatible, it will also tend to increase the waiting time for patients with blood group O, who already have the longest waiting time. It has therefore been objected that the program is materially unjust, because it further disadvantages the least advantaged. This objection appeals to John Rawls' difference principle. However, the context for which Rawls proposed that difference principle, is significantly different from the present one. Applying the principle here amounts to a lop-sided trade-off between considerations of need and considerations of overall utility. Considerations of formal justice, however, may lead to a stronger objection to LDLE programs. Such a program means that one O-patient on the waiting list is exempted from the application of the general criteria used in constructing the list because he has a special bargaining advantage. This objection is spelled out and weighed against the obvious attraction of LDLE in a situation of (extreme) organ scarcity.