Risk factors affecting second renal transplant outcome, with special reference to primary allograft nephrectomy.

Removal of a failed primary renal allograft was found by some groups to adversely affect the outcome of a second kidney transplant. Recent data does not support this view and fail to show any such effect. Such data, however, are limited by small numbers or univariate analysis. The records of 192 patients receiving a primary and a subsequent kidney transplant between January 1980 and July 1992 were retrospectively reviewed. Immunosuppression initially included azathioprine and prednisone; cyclosporine was introduced in December 1983 with Minnesota antilymphocyte globulin (MALG) added for induction in May 1987. Regraft survival rates were 66% at one year and 60% at two years. Using Kaplan-Meier survival analysis patients having primary transplant nephrectomy had a worse second allograft outcome than patients who kept their failed grafts (P = 0.0003). Multivariate analysis showed a significant relationship between primary allograft survival and retransplant outcome. To eliminate this influence, patients whose first graft failed within six months of transplantation were excluded from the analysis. This resulted in 90 patients whose first graft functioned for more than 6 months. Graft survival was 80% at one year and 73% at 2 years in this select population. Patients with prior transplant nephrectomy still had a worse retransplant outcome than those who kept their failed grafts (P = 0.05). Multivariate analysis identified primary allograft nephrectomy, older donor age, longer interval from nephrectomy to retransplant, and lack of MALG at induction as negative risk factors. In conclusion, primary allograft nephrectomy may have a negative influence on second renal transplant outcome. This result may be improved by reducing donor age and the time interval from nephrectomy to retransplantation, and using MALG at induction.