Is there a role for living donor intestine transplants?

Progress in Transplantation, Dec 2004 by Fryer, Jonathan, Angelos, Peter

Although the extensive use of HLA matching in solid-organ transplantation has been controversial, it remains highly relevant in some circumstances.37 With increasingly effective immunosuppressive drugs regimens, HLA matching appears to influence outcomes in kidney transplantation only at the extreme ends of the matching spectrum, when either no antigens match or when all antigens match.29 Although HLA matching with pancreas transplants has been shown to be beneficial,38 it appears to have no influence on results in liver transplants.39 Both heart and lung transplants appear to benefit from HLA matching, although few centers have utilized it when allocating organs.39 Currently, insufficient data exist to adequately determine if HLA matching influences outcomes in intestine transplants,35 although centers that actively seek optimal HLA matching in donor-recipient pairs report encouraging results.40 Although there are a few reports of intestinal transplantations between identical twins, no immunosuppression was required.12-14 There are little data on intestinal transplants between HLA identical siblings,41 although existing data appear favorable.

Because the incidence of rejection, graft loss, and death has been high with intestine transplants when no HLA matching has been attempted, the possible benefits of HLA matching needs to be evaluated further. HLA matching is also possible with deceased donor organs and the United Network for Organ Sharing currently prioritizes kidney allocation nationally to candidates with no HLA mismatches. In large organ allocation networks such as the United Network for Organ Sharing, a similar system could be utilized for the allocation of intestinal allografts, if the process could be completed before procurement to avoid prolonging ischemia time.42 Furthermore, with intestinal transplantation, other matching issues including donor-recipient size discrepancies and CMV statuses may take priority over HLA matching and would have to be incorporated into an allocation algorithm. In lieu of such an allocation process, it would be easier to achieve HLA matching with living donor organs. Therefore, at this time, the benefits provided by living intestine donors via better HLA matching remain hypothetical. However, on the basis of the overall experience without HLA matching, a proper evaluation of HLA matching in intestinal transplantation is clearly warranted. If HLA matching is shown to reduce the need for toxic levels of immunosuppression and/or decrease the frequency and severity of posttransplant septic complications,40 it will be worth the effort to implement because sepsis has been the leading cause of morbidity and mortality in intestine transplant recipients.