Long-term follow-up in children with steroid-resistant nephrotic syndrome.

A prospective study was performed in order to evaluate the efficacy of oral cyclophosphamide and chlorambucil in inducing a remission in children with steroid-resistant primary nephrotic syndrome (NS). Out of 215 children with steroid-resistant primary NS, 164 had been followed from one to 10 years. The children had a mean age of 8.2 years, with a range from one to 16 years. Steroid resistance was more common in children over six years of age compared with the other age groups. Hematuria was seen in 68 of the 164 children (41%); hypertension in 41 (25%); and hyperlipidemia in 112 (68%). Hypocomplementemia was noted in 24 of the 65 (37%) children in whom complement concentrations were determined. Renal biopsy was performed in 117 of the children. Pathologic changes consisted of minimal change nephrotic syndrome (MCNS) in 14 children (12%), membranoproliferative glomerulonephritis (MPGN) in 45 (38%), focal segmental glomerulosclerosis (FSGS) in 20 (25%), mesangial proliferation (MP) in 23 (20%), and membranous glomerulonephritis in six children (5%). Cyclophosphamide (2 mg/kg/day) was given to 164 patients, with complete remission and partial remission rates of 20.7% (34 of 164 children) and 24.4% (40 of 164 children), respectively. In this group, sustained remission and sustained partial remission rates were found in 20% (32 children) and 13% (21 children), respectively. Chlorambucil was given to 40 children with steroid- and cyclophosphamide-resistant nephrotic syndrome, with total remission and partial remission rates of 20% (eight children), and 12.5% (five children), respectively. These rates did not change during the follow-up. Thus, cyclophosphamide is valuable in the treatment of children with steroid-resistant NS with a variety of histologic changes.