Glomerulonephritis

Question 1

Clinical Classifications of glomerulonephritis

Answer 1

1. Nephritic syndrome - Blood and protein in urine, renal dysfunction and hypertension
2. RPGN - Progression renal failure over days to weeks usually with nephritic presentation with pathological finding of crescent formation on biopsy
3. Nephrotic syndrome - >3.5gms of proteinuria, hypoalbuminuria, hyperlipidaemia and oedema
4. Chronic GN - persistent proteinuria with or without haematuria and slowly progressive impairment of renal function

Question 2

Histological Classification of GN

Answer 2

1. Mesangial cell disease
   - IgA nephropathy
   - Diabetic GN
   - Class 2 lupus nephritis
2. Epithelial cell injury
   - Membranous nephropathy
   - Minimal change disease
   - Focal and segmental glomerulosclerosis
   - Class 5 lupus nephritis
3. Endothelial cell injury
   - Mesangiocapillary glomerulonephritis
   - Class 3 and 4 lupus nephritis
   - Anti GBM disease
   - Vasculitic disease
   - Cryoglobulinaemia
   - HUS

Question 3

Post-streptococcal GN

Answer 3

Usually children
Post group A beta haemolytic streptococcus infection

10-21 days after pharyngitis or impetigo

Acute nephritic syndrome - haematuria, proteinuria, oedema, HTN

Usually recovers without ongoing renal impairment

Question 4

Glomerular Basement Membrane disease

Answer 4

Antibody to alpha 3 type 4 collagen

Results in:

• Focal necrotising GN
• Pulmonary haemorrhage

IF = linear IgG staining

Treatment =

• plasma exchange
• prednisone and cyclophosphamide

Question 5

IgA Nephropathy

epidemiology and pathophysiology

Answer 5

Commonest cause of GN worldwide
White and Asian prevalence
M>F
20-30yrs

Usually idiopathic

Abnormal glycosylation of hinge regions of IgA –> Ag-Ab complexes –> mesangial deposition –> nephropathy

Question 6

IgA Nephropathy

Diagnosis and presentation

Answer 6

IF = IgA deposition and mesangial hypercellurlarity –> fibrosis
Only biopsy if severe

Presentation:
Recurrent haematuria - synpharyngitic with viral URTI or gastroenteritis
Chronic GN
HTN
CRF

Question 7

IgA nephropathy

Natural history and Treatment

Answer 7

Usually benign
10-20% CRF after 20yrs

Usually worse if nephrotic range proteinuria, HTN, high creatinine, old age or male

Treatment = control BP - ACE-Is
Pred if heavy proteinuria

Question 8

Henoch schonlein Purpura

Answer 8

Childhood with viral like prodrome –> lower limb rash, arthralgia, abdominal colic, haematuria and IgA nephropathy

Most resolve spontaneously
3-5%–> CRF

NSAIDS and steroids

Question 9

Thin membrane glomerulopathy

Answer 9

Thin GBM on EM <300nm

20-40% of haematuria

Presents with proteinuria
Usually have family history

Good prognosis

Question 10

Alports Syndrome

Answer 10

X linked genetic disorder - mutations in the genes coding the alpha chains of 3, 4 and 5 of type 4 collagen

Results in GBM splitting
–> haematuria, proteinuria and progressive CRF

Also have high frequency deafness

Question 11

Rapidly progressive glomerulonepritis

Answer 11

Renal failure <6 weeks
Haematuria, protienuria, oligouria, HTN, Rising Cr, haemoptysis, arthragia/myalgia, weight loss

Peaks 20-30yrs and >55yrs

ANCA associated vasculitis is the most common cause

Crescents >50% of glomeruli, interstital inflammation
Other histology dependent on cause of RPGN

Treatment = prednisone and cyclophosphamide
Plasmaphoresis if anti-GBM or ANCA as cause

–> 50% ESRF
High mortality - pulmonary haemorrhage, sepsis, renal failure

Question 12

Classes of lupus nephritis

Answer 12

Class 1 = Minimal change disease
Class 2 = Mesangial disease
Class 3 = Focal proliferative disease
Class 4 = Diffuse proliferative disease
Class 5 = Membraneous disease
Class 6 = Sclerosis

Question 13

Which classes of lupus need treatment?

Answer 13

Class 3-5

Class 3 and 4 =

• Pred and Cyclophosphamide or MMF for induction then
• Pred and azathioprine for maintenance

Class 5 =

• With normal Cr and minimal proteinuria = ACE-Is
• Proteinuria = Pred + cyclophosphamide or CNI or MMF or azathioprine