Nephrotic syndrome

At a glance

• Nephrotic syndrome: proteinuria over 3.5 g/day (UPCR over about 300 mg/mmol), serum albumin under 30 g/L, and oedema, usually with hyperlipidaemia. The definition and oedema mechanisms are in Oedema.
• It reflects podocyte injury: a bland urine with few red cells, unlike nephritic syndrome.
• In adults, the main primary causes are membranous nephropathy, FSGS and minimal change disease. Diabetic kidney disease is the commonest secondary cause.