 In most cases, the pathogenesis of NS remains elusive, and the clinical phenotype of patients does not allow discrimination among different causes. Thus, children with NS are usually treated with corticosteroids before a biopsy is taken, and approximately 80 of them respond to such a treatment. According to this observation, pediatric NS has been separated into two broad categories; Steroid-Sensitive Nephrotic Syndrome SSNS and Steroid-Resistant Nephrotic Syndrome SRNS. In both these categories the biopsy result is usually Minimal Change Disease MCD while a few may show Focal and Segmental Glomerulosclerosis FSGS. Although children affected by SSNS have good long-term prognosis, most patients with SRNS progress to End Stage Renal Disease ESRD within 2-10 years of diagnosis . 