Acute Glomerulonephritis

Question 1

Define

Answer 1

minimal change disease, focal-segmental glomerulosclerosis, membranous; causes:
* Post-infectious (streptococcus in children)
* Vasculitis - e.g. HSP, SLE, Wegener granulomatosis, microscopic polyarteritis, polyarteritis nodosa
* IgA nephropathy (adults, but includes HSP in children)
* Mesangiocapillary glomerulonephritis
* Goodpasture’s

In acute nephritis, increased glomerular cellularity restricts the glomerular blood flow and thus GFR is reduced.

This leads to:
* Decreased urine output and volume overload
* Hypertension- may cause seizures
* Oedema- initially periorbital
* Haematuria + proteinuria

There may be rapid deterioration in renal function (rapidly progressive glomerulonephritis)- this can occur with any cause of acute nephritis. If untreated, it can lead to CKD

 
Range of immune mediated disorders  inflammation in the glomerulus and other kidney compartments, 1st or 2nd:
1. Minimal change
2. Diffuse (all glomeruli)
3. Focal (some glomeruli)
4. Segmental (only parts of affected glomerulus)

Question 2

Minimal change disease

Answer 2

Children 2-4yo, 90% nephrotic syndrome

Normal renal function / complement / BP

Usually responds to high dose prednisolone (steroid-sensitive nephrotic syndrome)

Question 3

Focal segmental glomerulonephritis

Answer 3

Segmental scarring and foot process fusion, common in older children

HTN, impaired renal function

50% respond to steroids and 50% ESR

Question 4

Membranous nephropathy

Answer 4

Widespread thickening, granular deposits of Ig and complement, more common in adults

Question 5

Signs and symptoms

Answer 5

Nephrotic syndrome – low albumin, oedema, proteinuria

Nephritic syndrome – haematuria, HTN, proteinuria

Decreased urine output and volume overload / oedema

Hypertension and seizures

Other symp N
* Fever
* Malaise
* Weight loss
* Haemoptysis

Question 6

Investigations

Answer 6

Urine dipstick testing, urea, U&Es, urine MC&S, urinary sodium

FBC, ESR, creatinine, albumin

• Spot urine albumin: creatinine ratio (ACR)

Complement levels (C3, C4)

ANCA

Anti-GBM antibody

Anti-streptolysin O or anti-DNase B titres (recent streptococcal throat infection)

HBV, HCV, malaria screen

Kidney USS

Question 7

Management

Answer 7

Depends on type, severity and complications § Minimal change -> see “Nephrotic Syndrome” / corticosteroids

Focal-segmental -> depends on cause…

• Corticosteroids
• Immunosuppressive drugs
• Plasmapheresis
• ACE inhibitors and ARBs
• Diuretics
• Diet change

Membranous ->supportive, ACEi and ARBs

o Correct water and electrolyte balances

o Treat oedema with diuretics and potassium supplement

o BP management, dietary advice, lipid lowering therapy

Question 8

Post-streptococcal and Post-infectious Nephritis

Answer 8

Usually followed by streptococcal sore throat or skin infection

Diagnosed by evidence of:

Recent streptococcal infection

Culture of organism, raised anti-streptolysin O/ anti-DNase B titres:
* Anti-streptolysin O titre: detects most strains of group A streptococcus
* Anti-DNase B titres: detects group A b-haemolytic streptococci

LOW complement (C3) levels
* Returns to normal after 3-4 weeks

Long term prognosis is GOOD