OBSERVATIONS ON RECOVERY OF RENAL-FUNCTION FOLLOWING TREATMENT FOR ACUTE REJECTION

The characteristics of rejection and rejection response have not been systematically described in renal transplant recipients. The Efficacy Endpoints Conference Database contains characteristics from 953 episod es of rejection occurring at 19 North American, European, and Australi an transplant centers. This database was used to profile renal transpl ant rejection episodes treated with primary steroid therapy, primary a ntilymphocyte antibody therapy, and rescue antilymphocyte antibody the rapy. Primary steroid therapy was used in 88% of the rejection episode s. A successful response was more common in recipients without fever ( 72% v61%; P < 0.004), in recipients experiencing less than a Banff Gra de III rejection (92% v 75%; P = 0.009), and was more likely associate d with graft function at 1 year following the rejection than rejection episodes that failed steroid therapy (89% v82%; P = 0.013). Steroid s uccess was statistically identifiable by day 2 of therapy and clinical ly useful by day 3; serum creatinine on these days of therapy is shown as a ratio of the rejection creatinine (102% v112% day 1,success vfai lure, P < 0.002; 104% v122% day 2, success vfailure, P < 0.0001; 105% v125% day 3, success vfailure, P < 0.0001). Response to primary antily mphocyte antibody therapy reached significance at day 5 of therapy whe n serum creatinine decreased below the rejection creatinine level in a ntilymphocyte successes but remained at or above the rejection creatin ine in those who failed the therapy (90% v135%; P < 0.01). For rescue antilymphocyte antibody therapy, a response was evident after 5 days o f therapy (approximate to day 9 to 10 of rejection) when serum creatin ine began to decline and continued lower throughout the 10-day course of antilymphocyte antibody therapy (day 14 to 15 of rejection; serum c reatinine 3.0 mg/dL v4.4 mg/dL for success vfailure; P < 0.004). Serum creatinine was lower throughout the first year following therapy in e ach success group (steroids, antilymphocyte antibody therapy as primar y or as rescue), and a greater percentage of failures of any of the th ree therapies resulted in graft loss. Interestingly, 1-year graft surv ival was not different in the patients who were treated with antilymph ocyte antibody therapy as primary than those who received these antire jection agents as rescue therapy (81% and 84%, respectively). The Effi cacy Endpoints Conference Database provides an essential tool for prof iling acute rejection in renal transplantation and should lead to impr oved evaluation of rejection therapies. (C) 1998 by the National Kidne y Foundation, Inc.