• Monoclonal antibody OKT3;
  • Pancreas transplantation;
  • Rejection;
  • Technetium scanning;
  • Urinary amylase

Abstract. A major problem in vascularized pancreas transplantation is the lack of reliable methods for the early diagnosis and effective treatment of allograft rejection. Over a 2-year period, 54 rejection episodes occurred in 31 patients (13 isolated pancreas, 18 simultaneous pancreas-kidney recipients) with pancreaticoduodenocystostomy. A total of 253 radionuclide pancreas examinations were performed (mean 8.4 per patient) utilizing 99mtechnetium-DTPA. Computer analysis generated a quantitative measure of blood flow to the allograft caused the technetium index (TI). Rejection episodes were characterized as isolated pancreas (22), combined pancreas-kidney (16), or isolated renal (16) allograft rejection in combined engraftments. The majority of rejection episodes occurred early (within 3 months of transplant, N=47) and were more responsive than late rejection to anti-rejection therapy (89.4% vs 42.9%, P= 0.01). Mean urinary amylase (UA) levels and TI during normal allograft function were 29,398 U/l and 0.55%, while levels heralding rejection were 6,528 U/l and 0.40%, respectively (P < 0.05). The treatment of rejection based upon renal dysfunction or combined renal and pancreas dysfunction resulted in significantly higher graft salvage with a lower incidence of hyperglycemia when compared to isolated pancreas allograft rejection. Of the 11 patients who developed hyperglycemia, 8 (72.7%) ultimately lost their pancreas grafts (P < 0.001). Following therapy, a TI above 0.3% was associated with 97.4% graft survival, while levels below 0.3% resulted in a 70% rate of graft loss (P < 0.001). Similarly, pancreas allografts with a UA above 10,000 U/l had 91.1% functional survival, while levels below 10,000 U/l resulted in a 66.7% rate of graft loss (P < 0.001). Overall, reversal of rejection occurred in 83.3% of cases, with 9 grafts lost due to rejection at a mean of 4.7 months post-transplant. Therapy with ALG or OKT3 was more effective in reversing allograft rejection than pulsed corticosteroids alone (68.8% vs 47.9%, P= 0.05). Patient and pancreas allograft survival is 96.8% and 67.7%, respectively, after a mean follow-up interval of 14.9 months. Monitoring pancreas allograft function by UA, TI, and renal function (in simultaneous transplants) allows for the timely diagnosis and successful treatment of pancreas allograft rejection.