The Effect of Age at Onset on the Prognosis of Childhood Steroid-Sensitive Nephrotic Syndrome

Minimal change nephrotic syndrome(MCNS) is the most common form of Idiopathic Nephrotic Syndrome(INS) in childhood. Although most of the children with INS respond to steroid, a majority of them have subsequent relapses. In this study the effect of age at onset on the outcome of steroid-responsive nephrotic syndrome(NS) was evaluated. Medical records of all children with INS(1-10 years old) and initial response to steroid were reviewed. They had been followed for at least 7 years, and age of onset, sex, number of relapses, pathology report and other immunosupressive therapy were considered. They were studied in 3 age groups: 1-3 years, 4-6 years and 7-10 years at the onset of NS. Sixty-one children(46 boys and 15 girls) were included in this study. There were 23, 24 and 14 children in the above-mentioned age groups respectively. Kidney biopsy had been done for 46 children 76.5% of whom had MCNS. Cyclophosphamide, chlorambucil and cyclospurin had been used for 18.4 and 1 of them respectively. Children with onset of NS at 1-3, 4-6 and 7-10 years of age had(mean±SD) 7±5.92, 4.54±3.74 and 1.57±1.81 of relapses respectively. The duration of disease was also 5.52±4.15, 5.37±3.57 and 1.92±1.54 years respectively. Regarding the number of relapses and duration of disease, the differences between the 7-10 years age group and the other 2 groups were statistically significant(P<0.05). It can be concluded that age at onset is a reliable predictor of the course and prognosis of childhood steroid-responsive NS.