steroid-responsive nephrotic syndrome of childhood

Cyclophosphamide has been shown to be effective in preventing relapse of steroid-responsive nephrotic syndrome of childhood (Barratt and Soothill, 1970). However, a similar significant effect was not observed by Abramowicz et al. (1970), in a doubleblind trial of azathioprine. This drug was administered in a dosage of 60 mg/M2 surface area per day for 6 months to steroid-responsive nephrotic children, maintained on intermittent prednisone. This study did show, however, that there was a nonsignificant trend toward fewer relapses in the treated group. We thought that their use of intermittent prednisone militated against detection of a therapeutic effect of azathioprine because of the low rate of relapse in the placebo group. In view of the anxiety about the side effects of cyclophosphamide (Fairley, et al., 1972), we felt that it was necessary to re-examine the possibility that azathioprine might enhance the stability of remission in those patients.