LIVER TRANSPLANT RECIPIENTS WITH POSITIVE T-CELL

LIVER TRANSPLANT RECIPIENTS WITH POSITIVE T-CELL CROSS-MATCHES HAVE EXCESS MORTALITY.

MS Pollack, R Havranek, GA Halff, RM Esterl, WK Washburn, FG Cigarroa and KV Speeg, Departments of Surgery and Medicine, University of Texas Health Science Center, San Antonio, TX

Although it is widely believed that presensitized liver transplant recipients do not suffer immunological consequences that affect graft function, we have noticed that patients with positive crossmatches appeared to have excess mortality. Since our transplant population is predominantly Hispanic, it seemed important to review the role of immunological factors in this relatively unstudied population. Data for all recipients of liver transplants at our Institution were reviewed.To assure uniformity in crossmatch testing and antibody specificity evaluation, the analysis was confined to transplants within the past three years.Patients were required to have had at least one month post transplant follow-up and all patients who died within 30 days of their transplant due to peri-operative complications such as sepsis or hemorrhage were excluded.Data for a total of 188 patients were analyzed.These patients all had donor T-cell crossmatches and antibody specificity analyses performed by both the “Amos-wash” and antiglobulin enhanced microcytotoxicity procedures.Among patients with positive crossmatches due to known HLA antibodies with specificity for donor class I mismatched antigens, mortality was 15.4% whereas it was only 7.4 % among patients with negative crossmatches.Although the difference was not statistically significant, causes of death in the former group included malignancies, TB and recurrent virus infection that could have been related to the increased immunosuppression needed to treat rejection episodes (OKT3 in one case) that were also increased in that group.There was also a statistically significant increase in mortality among patients who suffered biopsy proven rejection episodes in comparison with those whose biopsy results were negative (odds ratio = 9.04; P = 0.0265, 2-sided Fisher’s exact test).Results of additional analyses including possible effects on patient survival and/or rejection of donor and recipient age, donor and recipient ethnicity, mismatched HLA antigens and PRA will also be presented.