Steroid-resistant nephrotic syndrome:: long-term evolution after sequential therapy

We present a retrospective study of 30 children of mean age 3.02 +/- 1.81 years with steroid-resistant nephrotic syndrome (SRNS) treated with intravenous injection of methylprednisolone plus orally administered prednisone; 24 children also received cyclophosphamide (CP). Sixteen were resistant to steroids from the beginning, and 14 after a mean of 11.26 +/- 16.61 months. The initial histological diagnosis was: 18 minimal change disease (MCD), 11 focal segmental glomerulosclerosis (FSGS) and one diffuse mesangial proliferative glomerulonephritis (DMPG). Total remission was achieved in 22 patients (73.3%), partial response in three (10%) and no response in five (16.6%), two of whom were brothers carrying an NPHS2 gene double mutation. There was no difference in response between the MCD and FSGS patients; the only patient with DMPG did not respond. Only initial resistance was a sign of bad prognosis. At follow-up (6.4 +/- 3.6 years from last pulse), 21/22 were still in remission, 14/21 were without treatment. Six patients required cyclosporine or mycophenolate mofetil because of steroid dependence. Two non-responders developed end-stage renal failure (ESRF); the remaining patients maintained normal glomerular filtration. The treatment was well tolerated. In conclusion, most of the patients treated with sequential therapy consisting of methylprednisolone (MP) (100%) and CP (80%) showed remission and preserved renal function, but 20% developed steroid dependence.