HLA-identical renal transplants: impact of cyclosporine on intermediate-term survival and renal function

Seventy-two and 34 consecutive HLA-identical sibling renal transplant recipients were treated with azathioprine/prednisone (AZA; follow-up, 5.0 years) and cyclosporine/prednisone (CSA; mean follow-up, 2.9 years), respectively. Both groups were similar in age, sex, race, and number of transplants, but there were more diabetics in the CSA group (34% v 8%). Actual patient survival at 1 year and actuarial patient survival at 5 years were 100% and 96%, respectively in the CSA group compared with an actual patient survival of 91% and 82% at 1 and 5 years, respectively, in the AZA group. Actual graft survival at 1 year improved from 85% in the AZA group to 97% in the CSA-treated recipients (P less than 0.05). Mean serum creatinine at 5 years remained stable in the AZA group at a mean of 123 mumol/L (1.4 mg/dL) compared with a progressive increase in this parameter to a mean of 212 mumol/L (2.4 mg/dL) after the same time interval in the CSA patients. Furthermore, the slopes of the serum creatinine against time were significantly different between the two groups (P less than 0.01). Mean daily CSA dose averaged 4 mg/kg 12 months following transplantation, with a decrease to 2.4 mg/kg by the fifth year. Causes of death in the AZA group were cardiovascular (eight), sepsis (three), cancer (one); and in the CSA group, Kaposi's sarcoma (one). Causes of graft failure in the AZA group were immunological (six), sepsis (three), technical (two), recurrence of disease (one), and patient death with a functioning graft (five). Technical (one), noncompliance (two), recurrence of disease (one), and patient death with a functioning kidney (one) caused graft failure in the CSA group. No difference in posttransplantation serum cholesterol or incidence of new onset diabetes was observed between the two groups, but hypertension was significantly more frequent (51% v 21%, P less than 0.01) when CSA was used. In conclusion, intermediate-term results of CSA-treated HLA-identical transplant recipients showed improved patient and graft survival with less complications apart from hypertension. However, the slow, but relentless, increase in serum creatinine in the CSA-treated patients compared with those treated with AZA is of concern.