Long-term follow-up of children with steroid-responsive nephrotic syndrome

Background: Nephrotic syndrome is one of the most remarkable diseases in childhood. The majority of patients have prompt response to corticosteroids. Methods: In this study, we retrospectively evaluate the outcome of patients with steroid-responsive nephritic syndrome. Medical records from January 1996 to September 2006 were reviewed to identify all children with steroid sensitive nephrotic syndrome at the Pediatric Medical Center, Tehran, Iran. Initial steroid therapy was 60 mg/m2 per day for four weeks. Levamisole, a steroid-sparing agent, was prescribed at a dose of 2.5 mg/kg on alternate days in conjunction with alternate-day prednisolone. If no benefit was observed by three months, levamisole was discontinued and immunosuppressive therapy with cyclophosphamide at a dose of 3 mg/kg daily for 8 weeks, or cyclosporin A at a dose of 3-5 mg/kg was prescribed.   Result: Of 745 children with steroid sensitive nephrotic syndrome, 63.1% of patients were male. The most common causes were minimal change disease (98/324, 30.2%) and focal segmental glomerulosclerosis (81/324, 25%). At presentation, microscopic hematuria was found in 22.6% of the patients. During follow-up, 9.2% had no relapse at any time, while 15.8% were frequent relapsers. The remission period ranged from 3.5 to 168 months. At the last follow-up, 57.6% of the patients were in remission, 37.7% relapsed and 29 children developed chronic renal failure. The outcome of nephrotic syndrome was not associated with age or gender. The end clinical status of patients correlated with duration of remission, number of subsequent relapses and response to cytotoxic agents.Conclusions: Steroid-responsive nephrotic syndrome in children should be followed over a long period, especially patients with early relapse. Relapse was seen in more than 90% of patients. Documentation of histopathology by renal biopsy may be helpful to identify those at increased risk for a poor outcome