[Treatment of idiopathic nephrotic syndrome in children].

The annual incidence of the nephrotic syndrome has been estimated to be 1-3 per 100,000 children<16 year of age. In children, the most common cause of nephrotic syndrome is idiopathic nephrotic syndrome (INS). INS is defined by the presence of proteinuria and hypoalbuminemia and by definition is a primary disease. Renal biopsy study shows non-specific histological abnormalities of the kidney including minimal changes, focal and segmental glomerular sclerosis, and diffuse mesangial proliferation. Steroid therapy is applied in all cases of INS. Renal biopsy is usually not indicated before starting corticosteroid therapy. The majority of patients (80-90%) are steroid-responsive. Children with INS who do not achieve a complete remission with corticosteroid therapy commonly present focal and segmental glomerular sclerosis and require treatment with calcineurin inhibitors (cyclosporine or tacrolimus), mycophenolate mofetil or rituximab, plus renin-angiotensin system blockade. In this article we review the recent accepted recommendations for the treatment of children with INS.