Post-streptococcal glomerulonephritis

Question 1

Post-streptococcal glomerulonephritis?

Answer 1

• Cause of acute glomerulonephritis
• Post-streptococcal glomerulonephritis typically occurs 7-14 days following a group A beta-haemolytic Streptococcus infection (usually Streptococcus pyogenes).
• It is caused by immune complex (IgG, IgM and C3) deposition in the glomeruli. Young children most commonly affected.

Question 2

Caused by?

Answer 2

• Infection of Group A beta haemolytic strep.
• Immune mechanism

Question 3

Features?

Answer 3

• general: headache, malaise
• haematuria
• proteinuria
• hypertension/fluid overload
• low C3
• raised ASO titre
• smokey urine

Question 4

IgA nephropathy and post-streptococcal glomerulonephritis are often confused as they both can cause renal disease following an URTI

Answer 4

Question 5

Investigations?

Answer 5

• Red smokey coloured urine
• Proteinuria<3g daily
• Raised urea and creatinine
• C3/C4 proteins down
• ASO and anti DNAse titres up
• Renal biopsy shows Ig3 and C3 deposits

Question 6

Renal biopsy features?

Answer 6

• post-streptococcal glomerulonephritis causes acute, diffuse proliferative glomerulonephritis
• endothelial proliferation with neutrophils
• electron microscopy: subepithelial ‘humps’ caused by lumpy immune complex deposits
• immunofluorescence: granular or ‘starry sky’ appearance

Question 7

Proliferation of endothelium and mesangium with recruitment of neutrophils. Tubules are normal:

Answer 7