Nephrotic Syndrome

Question 1

What is nephrotic syndrome?

Answer 1

It is the quadrad of signs and symptoms:
Heavy proteinuria
Hypoalbuminaemia
Generalised oedema (due to oncotic pressure)
Hypercholestrolaemia 

nephrOtic think Oedema

Question 2

What is nephritic syndrome?

Answer 2

In lay terms represents worse damage

Proteinuria
Haematauria and urinary red cell casts
High BP
Oliguria

Question 3

What is the aetiology of the symptoms in nephrotic syndrome?

Answer 3

Increased glomerular permeability to large molecules: (proteins and albumin)

This causes proteinuria and hypoalbuminaemia.

The oedema is a result of oncotic pressures due to the low albumin.

Question 4

What are the primary causes of nephrotic syndrome?

Answer 4

Idiopathic membranous nephropathy (most common cause in adults)

Focal segmental glomerulosclerosis (most common cause in black races)

Minimal change disease (most common cause in children)

Question 5

What are the causes the pathophysiology in idiopathic membranous nephropathy?

Answer 5

Inflammation of the glomeular arterioles associated with protein leakage.

Can be caused by: 
– Malignancy
– Drugs (Gold, Penicillamine,
Captopril)
– Autoimmune (RA, SLE)
– Infections

Question 6

What is the pathophysiology in focal segmental glomerulosclerosis?

Answer 6

Scarring of certain sections of glomerulus seen on renal biopsy. Leads to protein leakage which can lead to nephrotic syndrome.

In 30-50% of cases the patient will develop end stage renal failure in 10 years.

Question 7

What are the causes of focal segmental glomerulosclerosis?

Answer 7

Vesicoureteric reflux

IgA Nephropathy

Vasculitis

Sickle Cell

Heroin use

Alport’s syndrome (congenital syndrome)

Question 8

What occurs in minimal change disease?

Answer 8

There is a diffuse loss of podocyte processes leading to leakage of albumin.

It is an autoimmune T-lymphocyte mediated condition.

It is called minimal change disease as historically on microscopy there was minimal change that could be seen.

Question 9

What are the causative associations with minimal change disease?

Answer 9

Hodgkin’s Lymphoma

Drugs (NSAIDs)

Question 10

What are the secondary causes of nephrotic syndrome?

Answer 10

Main secondary causes are:

Diabetic nephropathy
Drugs
SLE

Other causes are:

Secondary:

Vascular: Pre eclampsia, Vasculitis, HSP

Infection: HIV, Hep B & C, Malaria, Schistosomiasis, Syphilis, Toxoplasmosis

Autoimmune: Transplant rejection

Metabolic: DM, Amyloid

Inflammatory: SLE, rheumatoid arthiritis

Neoplasm: Myeloma, lymphoma, leukemia

Drugs: NSAIDs, Lithium, Dimorphine

Question 11

How should nephrotic syndrome be investigated?

Answer 11

Bedside:
Urinalysis (expect to see proteinuria)

Bloods:

• FBC, LFTs, U&E’s
• Lipid profile, Coagulation screen, Bone profile
• Infection screen if suspected

Imaging:
USS
CXR (if sob think pulmonary oedema)

Renal Biopsy (needed to find underlying cause and guide treatment)

Question 12

How should nephrotic syndrome be treated?

Answer 12

Fluid restriction
Limit dietary sodium
High dose diuretics

In children with minimal change disease steroids have a role.