Focal segmental glomerulosclerosis accounts for approximately 20% of cases of the nephrotic syndrome in children and 40% of such cases in adults. The cardinal feature is progressive glomerular scarring. This review of the condition discusses the following topics:

• Clinical features
• Pathogenesis
• Pathological definition
• Primary (idiopathic) disease
• Virus-induced disease
• Drug-induced disease
• Disease secondary to hemodynamic adaptations
• Prognostic features
• Therapy
• Recurrence after kidney transplantation