Purpose: We retrospectively evaluated the outcome of transplantation with kidneys with 6 antigen HLA mismatches.
Materials and methods: From October 1990 to September 2001, 1,270 cadaveric renal transplants were performed at our center, including 33 (2.59%) involving recipients of kidneys with 6 antigen HLA mismatches. Mean recipient age +/- SD was 40.2 +/- 14.4 years. Of the 33 recipients 19 were male, 14 were female, 31 received an initial transplant, 4 had diabetes and 6 had panel-reactive antibodies of greater than 10%. Mean donor age was 30.3 +/- 13.7 years and mean cold ischemia time was 22.9 +/- 7.8 hours. All recipients had negative current and previous B and T-cell lymphocytotoxicity cross-matching and all received a triple immunosuppression regimen consisting of the calcineurin inhibitor cyclosporine or tacrolimus combined with steroids and azathioprine.
Results: One-year patient and graft survival was 93.3% and 93.7%, respectively. Of the 33 grafts 31 (94%) functioned immediately. During the mean followup of 3.31 years 10 grafts (30%) were lost, including 6 (60%) due to death with a functioning graft and 4 due to chronic rejection. Acute rejection in 8 patients (24%) was reversed in 7 by steroid pulses. No graft was lost to acute rejection. Technical complications included wound infection in 2 patients (6%), transplant-ureteral obstruction in 1 (3%) and a urinary fistula in 1 (3%).
Conclusions: Kidneys with 6 antigen HLA mismatches can be used effectively.