The Nephrotic Syndrome

Hospital Physician October 2007 25 T he nephrotic syndrome is a constellation of renal and extrarenal manifestations that can be caused by a multitude of systemic diseases as well as by primary insults to the kidney. The prevalence of the syndrome depends largely on the underlying causes, which vary significantly by age of onset. The nephrotic syndrome is classically characterized by 6 main abnormalities of which proteinuria of greater than 3.5 g/24 hr is the cornerstone. The cardinal manifestations of the nephrotic syndrome include edema, hypoalbuminemia, hyperlipidemia, and lipiduria. Hypercoagulability is also a well-known complication of the nephrotic syndrome. Because of the diversity of disease processes that can cause the nephrotic syndrome, the prognosis and treatment vary dramatically depending on the underlying etiology. This article reviews the presentation, complications, and common underlying causes of the nephrotic syndrome and briefly discusses the diagnostic work-up and treatment.