HLA-DR7 PREDICTS THE RESPONSE TO ALKYLATING-AGENTS IN STEROID-SENSITIVE NEPHROTIC SYNDROME

There is a lack of reliable predictors of the response to alkylating a gents in children with idiopathic nephrotic syndrome (NS). HLA-DR7 is strongly associated with the frequency of relapses in steroid-sensitiv e NS before cytostatic therapy. We therefore examined retrospectively the time to the first relapse and the incidence of subsequent relapses in 54 HLA-typed children with frequently relapsing NS, after treatmen t with cyclophosphamide (n = 49) or chlorambucil (n = 5) for 8 or 12 w eeks; 38 patients were HLA-DR7 positive and 16 negative with 80% in bo th groups being steroid dependent. HLA typing was performed using sero logical or DNA typing methods. Renal biopsy showed minimal glomerular changes. A lower proportion of HLA-DR7 positive than negative patients remained in remission after 3 years (36% vs. 81%, P < 0.02) and 5 yea rs (36% vs. 72%, P < 0.03). In the first 3 years after cytostatic ther apy the mean number of prednisone-treated relapses was 1.3/patient per year in HLA-DR7-positive patients compared with 0.4 in negative patie nts (P < 0.025). There was no statistically significant difference in the proportion of relapse-free patients with and without steroid depen dency. The HLA status predicts the response of NS patients to alkylati ng agents better than the rate of previous relapses.