PATTERNS OF ACUTE REJECTION IN PORTAL-ENTERIC VERSUS SYSTEMIC-BLADDERPANCREAS-KIDNEY TRANSPLANTATION

Portal-enteric (PE) transplantation of the pancreas allograft provides maintained physiologic drainage, and theoretically the portal deliver y of transplantation antigens may have beneficial effects on the graft acceptance leading to improved graft survival. To determine whether t he technique of pancreas placement affects the incidence of acute reje ction we reviewed our experience in technically successful PE and syst emic-bladder (SB) drained simultaneous pancreas and kidney (SPK) trans plants performed between 1989 and 1994. Forty-seven recipients were in cluded (SB = 30, PE = 17). All patients received cyclosporine based qu adruple immunosuppression and survived at least 1 month. The two group s were comparable in HLA mismatches, cold ischemia time and level of i mmunosuppression at time of rejection. In the SE group the incidence o f rejection was 1.04 kidney rejection/patient and 0.90 pancreas reject ion/patient whereas the PE group experienced 0.53 kidney rejection/pat ient and 0.47 pancreas rejection/patient. The two groups were compared using incidence density statistics due to great variation in follow-u p time. The SE group had a significant higher density of both kidney a nd pancreas rejections (p less than or equal to 0.037 for kidney rejec tion and 0.058 for pancreas rejection). In addition, while 6 of 30 (20 %) pancreas grafts and 4 of 30 (13%) kidney grafts were lost to irreve rsible rejection in the SE group, only 1 of 17 (6%) pancreas graft and 1 of 17 (6%) kidney graft were lost in the PE group. These data demon strate, that the PE placement of pancreas allograft affects the rates of acute rejection and graft loss, and imply that there exist some imp ortant immunological advantages when the pancreas graft is drained int o the portal circulation.