Background: The incidence of acute rejection is considered to be higher after simultaneous pancreas-kidney (SPK) transplantation as compared to renal transplant alone. Therefore, the majority of SPK transplant recipients commonly receive a combination of cyclosporine (CsA) or tracolimus, and azathioprine or mycophenolic mofetyl, corticosteroids and/or antilymphocyte preparations. This study was designed to compare two immunosuppressive protocols for the prevention of acute rejection in patients undergoing SPK transplantation. The primary end-point was the incidence of acute rejection during the first 12 months after transplantation
Methods: Fifty patients with type-I insulin-dependent diabetes and chronic renal failure were randomized to receive a triple drug immunosuppressive regimen including CsA, azathioprine and corticosteroids (N = 25), or the quadruple sequential combination of rabbit antithymocyte globulin (ATG) given for 10 days, azathioprine, corticosteroids and delayed CsA (N = 25). Maintenance immunosuppression (CsA and azathioprine, without corticosteroids) was similar in both arms.
Results: The average follow-up was 36 months in both groups (range 9 to 60 months). No patient was excluded from the study. Although the percentage of patients with adverse events was higher in the ATG group (80 vs. 40%, P < 0.01), none of them resulted in premature discontinuation of the drug. Patients receiving ATG experienced a lower incidence (36% vs. 76%, P < 0.01) and number (13 vs. 29, P < 0.05) of acute renal rejection episodes. However, no difference was observed in patient, pancreas and kidney survival rates between groups. No case of isolated pancreas rejection was observed.
Conclusions: The quadruple sequential combination ATG, azathioprine, corticosteroid and CsA significantly reduced the one year incidence of acute renal rejection after SPK transplantation, compared to a triple immunosuppressive regimen.