Nephrotic syndrome may be caused by primary (idiopathic) renal disease or by a variety of secondary causes. Patients present with marked edema, proteinuria, hypoalbuminemia, and often hyperlipidemia. In adults, diabetes mellitus is the most common secondary cause, and focal segmental glomerulosclerosis and membranous nephropathy are the most common primary causes. Venous thromboembolism is a possible complication; acute renal failure and serious bacterial infection are also possible, but much less common. Thirteen children of Israeli-Jewish origin with SRNS and biopsy-proven FSGS and 15 children of both ethnic groups with steroid-responsive FSGS were tested, and none was found to have mutations in NPHS2.
Treatment of most patients should include fluid and sodium restriction, oral or intravenous diuretics, and angiotensin-converting enzyme inhibitors. Some adults with nephrotic syndrome may benefit from corticosteroid treatment, although research data are limited. Intravenous albumin, prophylactic antibiotics, and prophylactic anticoagulation are not currently recommended. In nephrotic syndrome, a variety of disorders cause proteinuria, often resulting in marked edema and hypoalbuminemia. Hyperlipidemia is a common associated finding.