Background: Graft survival following solitary pancreas transplantation has traditionally lagged behind that of simultaneous pancreas-kidney transplants. Thymoglobulin (TMG), a polyclonal rabbit-derived antilymphocyte antibody was originally introduced as treatment for acute rejection of renal allografts. However, data regarding the efficacy of TMG induction in solitary pancreas transplants is lacking. We present the 1-yr graft survival and acute rejection rate of 22 solitary pancreas transplants performed at the McGill University Health Centre using reduced dose TMG induction with lower dose tacrolimus and mophetil mycophenolate.
Patients and methods: Eighteen pancreas after kidney and four pancreas transplants alone were performed between January 1998 and October 2000 at McGill University. Induction therapy with TMG at a starting dose of 1.5 mg/kg/d was started 12 h post-operatively. The daily dose of TMG was held if the total leukocyte count was <2,500/mm3 or if the lymphocyte count was <100/mm3. Maintenance therapy was initiated with steroids (tapered to 20 mg prednisone orally once a day) tacrolimus (2 mg twice a day), and mofetil mycophenolate (1 g daily).
Results: Patients received three to seven doses of TMG over the first seven post-operative days at a dose of 0.85 +/- 0.27 mg/kg/d (mean +/- SD). The mean follow-up was 1.28 +/- 0.14 yr. The 1-yr patient and graft survival was 100% (22 of 22) and 96% (21 of 22), respectively. The 1 yr acute rejection rate was 27.3% (six of 22). Five of the six rejections responded to steroid boluses. One was refractory to steroids and TMG resulting in graft loss. Presumed rejections were diagnosed on the basis of decreasing urine amylase and/or hyperglycemia.
Discussion: Monitoring the total leukocyte and lymphocyte count resulted in a 43% reduction in the amount of TMG used compared with the recommended dosing. Despite the reduced amounts, patient and graft survival were excellent with acute rejection rates comparing favorably to other published series.