Outcomes after acute rejection in pancreas transplantation

M. Dong, A. Parsaik, N. Rostambeigi, W Kremers, P. Dean, R. Abraham, M. Prieto, M. Stegall, Y. Kudva
Mayo Clinic, Rochester, MN, USA

Objective: To evaluate the incidence, risk factors and outcomes of biopsy proven treated acute rejection (AR) among recipients of all three kinds of pancreas transplantation (PT).

Methods: We performed a retrospective review of all adult patients who received PT at our institution from 01/01/1998 to 12/31/2009. Late acute rejection (LAR) referred to the first episode of treated AR after 12 months of PT.

Results: Simultaneous pancreas and kidney (SPK), pancreas transplantation alone (PTA), and pancreas after kidney (PAK) transplantations were performed in 59 , 70, and 119 patients, with 52% males and mean age 43.7 ± 8.9 years. 88% of recipients received induction therapy with rabbit anti-thymocyte globulin (ATG), and 9% received OKT3. Tacrolimus, mycophenolate mofetil and prednisone were used as maintenance immunosuppressants after PT. Overall, 68 patients developed 108 episodes of AR during the median follow up of 6.3 (IQR 3-9) years, and 25 experienced more than one episode. The cumulative incidence of AR at 1, 2, and 5 years post transplant was 16%, 21%, and 30%. 43 % of first AR episodes occurred within the first six months after PT. The only variable significantly associated with recurrent AR was the type of transplantation with highest burden in PTA (P=0.0002). 28 patients experienced 42 episodes of LAR. The cumulative incidence of LAR at 2, 3 and 6 years post transplant was 5%, 6%, and 15%. LAR was associated with an increased risk of graft failure (HR=4.91, P<0.0001), while AR developing within 12 months post PT was associated with a borderline increased risk (HR=1.768, p=0.072). Pancreas graft survival was significantly lower in patients with LAR than that of AR within 12 months (P=0.014).

Conclusion: LAR was associated with an increased risk of pancreas graft failure.