HLA-IDENTITY - LONG-TERM RENAL GRAFT-SURVIVAL, ACUTE VASCULAR, CHRONIC VASCULAR, AND ACUTE INTERSTITIAL REJECTION

The object is analysis of the impact of acute and chronic rejection on long-term function in HLA-identical renal transplants performed from 1967 to 1995 by the Saskatchewan Renal Transplant Unit. Forty-eight gr afts in 46 patients were studied, of which 39 were first and nine seco nd grafts. Forty-two were for primary and six for secondary renal dise ase. Thirty-five received azathioprine/prednisone prophylaxis, and 13 received cyclosporine/prednisone with/without azathioprine. Ten-year a ll graft actuarial survival was 84%, 10-year actuarial graft survival in patients with primary renal disease 90%, and with subsequent graft after first HLA graft failed 97.5%, for age-matched population 98.5% ( P=NS). Overall death rate was 8.7% (4/ 46); in secondary renal disease patients 50% (3/6); in primary renal disease patients 2.5% (1/40, P=0 .004). All (9/9) HLA-identical second grafts functioned, Acute rejecti on with azathioprine/prednisone prophylaxis occurred in 55% (9/17) of grafts treated with <6 pre-graft blood transfusions, with the same pro phylaxis but >5 units in 12% (2/16, P=0.015), and with cyclosporine pr ophylaxis in 13% (2/15, P=0.021). Pulse steroids alone reversed all ac ute rejections. Grafts failed in 6.2% (3/48), all in primary renal dis ease patients and one from technical one noncompliance, and one chroni c rejection. Graft cost/patient/year amortized over 9 years is $3,855 and comparable dialysis cost would be $35,650; cost for all patients o n dialysis for 9 years would be $11,293,320 while comparable graft cos t was $1,221,418, a saving of 89.2%. Our conclusions are that HLA-iden tity associates with the following: (1) a 10-year actuarial survival i n primary renal disease that equals that of the age-matched population , (2) uniform success in repeat grafts, (3) virtual absence of chronic rejection despite a high incidence of acute rejection in azathioprine /prednisone grafts that (4) always reversed on pulse steroids, and (5) a cost reduction for grafting of 93.2% compared with dialysis therapy .