Improved patient and graft survival after treatment of acute rejections of cadaveric renal allografts with rabbit antithymocyte globulin.

In a prospective randomized trial, we compared the effectiveness of rabbit antithymocyte globulin (RATG) in the treatment of acute renal allograft rejection with the results of treatment by high oral doses of prednisone. Fifty recipients of cadaveric kidneys were included in each group. In the RATG group, the prednisone dose was not increased and a dose-by-rosette protocol was used to keep T cell levels between 50 and 150/mm. The three-month and one-year graft survival rates in the RATG group were 84% and 78%, and were significantly higher than those in the prednisone group (64% and 50%). A significant difference in patient survival could also be detected. In the RATG group the three-months and one-year patient survival rates were 100% and 98%, and patient survival rates in the prednisone group were 91% and 84%, respectively. The percentage of second rejections was higher in the prednisone group and 70% of these patients showed a good response to subsequent RATG treatment. Renal function after six months was similar in both groups. No serious side effects were encountered in the RATG group. The incidence of infections was the same in both groups. Treatment of acute rejections with RATG is preferable to prednisone treatment. It improves long-term graft and patient survival and is steroid-sparing.