A highly efficient living donor kidney exchange program for both blood type and crossmatch incompatible donor-recipient combinations

Background. Lack of deceased donors for kidney transplant patients in the Netherlands encouraged alternative options to expand the living donor pool for recipients who have a willing donor but cannot donate directly because of a positive crossmatch or ABO blood type incompatibility. A national donor kidney exchange was considered as a possible solution. Methods. From January 2004 until June 2006, 146 couples from seven kidney transplantation centers were enrolled and participated in 10 match procedures. The Dutch Transplant Foundation was responsible for the allocation and the National Reference Laboratory for Histocompatibility in Leiden performed all the serological crossmatches. Results. For 72 out of the 146 (49%) donor-recipient combinations, a match was found. The success rate in the positive crossmatch group was significantly (P=0.0015) higher than in the ABO-incompatible group (44/69 vs. 28/77); median panel reactive antibodies of the matched recipients in the positive crossmatch group was 38% (0-100) and in the ABO-incompatible group 0% (0-27; P < 0.001). We were least successful for ABO blood type incompatible pairs with blood type O recipients, but for 9/53 (17%) there were possibilities. These nine blood type incompatible pairs were coupled to nine positive crossmatch pairs, which reflects the efficiency of combining the two categories of donor-recipient combinations into one program. Conclusion. The donor kidney exchange program in the Netherlands, in which all seven kidney transplantation centers participated, proved to be a successful program to expand the number of living donor kidney transplantations.