IgA nephropathy

Question 1

What is IgA nephropathy?

Answer 1

• also called Berger’s disease or mesangioproliferative glomerulonephritis
• commonest cause of glomerulonephritis worldwide
• thought to be caused by mesangial deposition of IgA immune complexes, often post-infection
• there is considerable pathological overlap with Henoch-Schonlein purpura (HSP)
• histology: mesangial hypercellularity, positive immunofluorescence for IgA & C3

Question 2

How do you differentiate between IgA nephropathy and post-streptococcal glomerulonephritis?

Answer 2

• post-streptococcal glomerulonephritis is associated with low complement levels
• main symptom in post-streptococcal glomerulonephritis is proteinuria (although haematuria can occur)
• there is typically an interval between URTI and the onset of renal problems in post-streptococcal glomerulonephritis

Question 3

How does IgA nephropathy commonly present?

Answer 3

• young male, recurrent episodes of macroscopic haematuria
• typically associated with mucosal infections e.g., URTI
• nephrotic range proteinuria is rare
• renal failure
• recovery often rapid between attacks

Question 4

What conditions are associated with IgA nephropathy?

Answer 4

• alcoholic cirrhosis
• coeliac disease/dermatitis herpetiformis
• Henoch-Schonlein purpura

Question 5

What is the management of IgA nephropathy?

Answer 5

• BP control with ACE inhibitor

- With a nephritic presentation, immunosuppression may slow decline of renal function

Question 6

What is the prognosis in IgA nephropathy?

Answer 6

• 20% of adults develop ESRF over 20yrs.
• markers of good prognosis: frank haematuria
• markers of poor prognosis: male gender, proteinuria (especially > 2 g/day), hypertension, smoking, hyperlipidaemia, ACE genotype DD