Background: Despite Rristry data indicating that an increasing number of HLA mismatches (MM) significantly increases rejection risk and lowers graft survival, we hypothesized that solitary pancreas transplants could be successfully performed even in the presence of poor HLA matching if an aggressive approach were taken with regard to both immunosupperssive protocol and allograft biopsy.
Methods: Seven panceas-after-kidney (PAK) Transplants and 7 pancreas transplants alone (PTA) were performed from to 10/98 without consideration given to the degree of HLA MM using tacrolimus (FK506)/ mycophenolate mofetil (MMF)/ prednisone maintenance therapy. Mean (± SD) A/B, DR, and total HLA MM were 3.3 ± 0.9, 1.5 ± 0.5, and 4.8 ± 1.2, respectively. All patients were followed for at least 6 months. The first cases were induced with ATGAM for 7 to 10 days. In the remaining 10 cases, an ultrasound-guided percutaneous needle biopsy was attempted when possible on a protocol basis 10 days after completing induction with OKT3 for 7 (n = 2) or 14 (n=8) days.
Results: Overall patient survival, graft survival, and incidence of acute rejection requiring treatment were 86 %, 79 %, and 50 % respectively. Both deaths occurred in PAK Transplant recipients, one from pulmonary embolism at 6 months and the other from necrotizing candidal transplant pancreatitis and sepsis at 2 months. Two patients receiving ATGAM Developed grade III-V rejection at 3 weeks (one with graft loss), and both patients receiving OKT3 for 7 days developed early grade III rejection, Suggesting failure of induction in both these groups. Only 3 of 8 patients receiving OKT3 For 14 days developed rejection requiring treatment. Protocol biopsy was successfully performed in 6 of 7 patients and uncovered 3 cases of otherwise undetectable grade III-IV rejection.
Conclusions: Solitary pancreas transplants with a poor match can be successfully performed with an acceptable morbidity and rejection incidence using an OKT3/FK506/MMF/ prednisone regimen with protocol and as-needed percutaneous needle biopsy, particulary in PTA patients.
Abbreviations:FK506, tacrolimus, HLA MM, HLA mismatches; MMF, mycophenolate mofetil; PAK,Pancreas-after-kidney; PTA, pancreas transplant alone; SPK, simultaneous pancreas/kidney