1.2000
#38-OR
IMMUNOCOMPATIBILITY SCREENING FOR PAIRED KIDNEY EXCHANGE TRANSPLANTS.
S. Hibbett, D. Phelan, J. Lowell, N. Desai, M. Jendrisak, S. Shenoy and T. Mohanakumar. Barnes-Jewish Hospital HLA Laboratory and St. Louis MO, USA, Washington University School of Medicine, 63110, Dept of Surgery.

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In recent years, both nationally and locally, an increasing number of patients have been added to the renal transplant wait list due to a shortage of deceased donors available for transplantation. This necessitates developing strategies to increase living donor (LD) donation. The goal of our study is two fold: 1) Determine whether direct exchanges between LD recipients which would be excluded due to positive crossmatch and/or ABO incompatibility are possible 2) Develop strategies to offer exchanges between living donor-recipient pairs within our center. Potential candidates for a living paired kidney exchange were first identified by positive crossmatches. Our center currently has 29 recipients with 70 potential donors to average 2.4 donors/recipient. Specificity of recipient antibodies to HLA resulting in positive crossmatch was then identified using ELISA and cytotoxicity methods. Mismatched antigens due to previous transplants were also determined for each recipient. The recipients were then matched with new potential ABO compatible LD based on both mismatched antigens and defined antibodies. 24 out of the 29 recipients (83%) were found to be exchange candidates with 31 possible exchange combinations. Significantly, each recipient was compatible with an average of 11.5 donors out of the pool of 70. Implementation of a living paired kidney exchange program is a viable option for LD renal transplantation of a significant number of sensitized recipients restricted by immunologic incompatibility. In addition, an exchange based on histocompatibility will dramatically reduce the need for current desensitization protocols that are costly and time consuming.