Chirag Desai, Angelika Gruessner, Khalid Khan, Rainer Gruessner

Department of Surgery, University of Arizona, College of Medicine, Tucson, AZ, United States

Introduction: The intestine is one of the most immunogenic organs and transplantation of it is associated with significant incidence of rejection. Human leukocyte antigen (HLA) mismatch on long-term outcome has been examined in few single center series. We analyzed the effect of HLA mismatch on outcomes after intestinal transplants (ITx) using the United Network for Organ Sharing (UNOS) database.

Methods: UNOS Standard Transplant Analysis and Research (STAR) files were used for this analysis.  All ITx from January 2001 were included.

Results: During this study period 1,223 patients received ITx, 529 (43.3%) were adults and 694 (56.7%) were pediatric patients. Of those, 530 (43.4%) were isolated ITx and 693 (56.6%) were liver-ITx (L-ITx). When we compared graft survival at 1, 3, and 5 years for patients with 0 and 1 mismatch at the individual locus vs. 2-antigen mismatch at the same locus for both adult and pediatric patients for each graft types, we found no statistical difference in outcome. The only statistically significant differences were: 1, 3, and 5 year graft survival for adult isolated ITx at A locus with 0 and 1 antigen mismatch was 85%, 64%, and 48% vs. 81%, 55%, and 37% for 2 antigen mismatch (P = 0.07). At B locus , with 0 and 1 antigen mismatch, graft survival was 86%, 68%, and 56%; with 2 antigen mismatch survival was 81%, 56%, and 39% (P = 0.08). Adult L-ITx patients with 2 antigen mismatch at DR locus had a slightly better outcome than those with 0 and 1 mismatch (P = 0.09) [72%, 62%, and 50% (with 2 mismatch) vs. 65%, 48%, and 45% (with 0 and 1)].

Conclusion: UNOS database analysis shows no significant impact overall of HLA mismatch on long term graft survival for patients undergoing a small bowel transplant.