Nephrotic syndrome is a disorder of the kidneys that results from increased permeability of the glomerular filtration barrier. It is characterized by 4 major clinical characteristics that are used in establishing the diagnosis: proteinuria, hypoalbuminemia, edema, and hyperlipidemia. This article reviews nephrotic syndrome in the pediatric population, with special attention paid to minimal change nephrotic syndrome. Nephrotic syndrome can affect children of any age, from infancy to adolescence, and is most commonly seen among school-aged children and adolescents. The prevalence worldwide is approximately 16 cases per 100,000 children with an incidence of 2 to 7 per 100,000 children.
The kidney uses a complex filtration system known as the glomerular filtration barrier (GFB). It is composed of a glomerular basement membrane sandwiched between a fenestrated endothelium and an epithelial layer made up of podocytes and their foot processes. Many cases are linked to the immune system, which normally protects the body against disease and infection. There are different types of nephrotic syndrome. It is often not possible to find out which type your child has until after they have taken a course of steroids.