Most patients with idiopathic nephrotic syndrome are steroid-responsive, but about 50% relapse and often become steroid-dependent and exposed to long-term steroid complications. The aim of this study was to determine predictive risk factors for steroid and/or cyclosporine A (CyA) dependence. In France, steroid responsiveness is defined as remission after 1 month of oral prednisone (60 mg/m(2) per day) and-in the case of persistent proteinuria on day 30-three methylprednisolone pulses (MPP; 1 g/1.73 m(2) on days 1, 3, and 5). Thirty-five steroid-responsive children, followed between 1999 and 2006, were included in this study. Median age at diagnosis was 4.9 years. All patients initially received prednisone 60 mg/m(2) per day. Twenty-four of the 35 patients were steroid-dependent, with 12 requiring MPP. Of the latter 12 patients, 83.3% were treated with CyA during follow-up; in comparison, only 16.7% of the patients who did not receive MPP required CyA during follow-up (chi-square test, P = 0.001). T risk for steroid dependence was 100% in our cohort if remission was achieved after day 20. Patients who need MPP are at high risk to require CyA to achieve disease control. By identifying these children, we could use adequate immunosuppressive drugs earlier and reduce morbidity related to steroids and multiple relapses.