Glomerular Disease (Clinical) Flashcards
What is glomerulonephritis? How is it classified?
- Group of immune mediated disorders that affect the glomeruli
- Classified based on kidney biopsy findings
What are some features of glomerulonephritis?
- Haematuria (visible / non-visible)
- Proteinuria (low grade or nephrotic)
- Hypertension
- Renal impairment
What are some features of nephritic syndromes?
- Haematuria
- Mild proteinuria
- Hypertension
- Renal impairment (low urine volume)
What are some features of nephrotic syndromes?
- Severe proteinuria (>3.5g/day or 350mg/mmol creatinine, urine may look frothy)
- Hypoalbuminaemia
- Oedema
- Hyperlipidaemia
Why is there hyperlipidaemia associated with nephrotic syndrome?
liver increases production in response to hypoalbuminaemia, excess production of lipids is a side effect
What are the two major types of glomerulonephritis? Difference between the two?
- Proliferative: excessive number of cells in the glomeruli, include invading leukocytes
- Non-proliferative: glomeruli look normal or have areas of scarring, normal cell number
List some descriptive terminology used when describing glomerulonephritis
Diffuse: >50% of glomeruli affected
Focal: <50% of glomeruli affected
Global: all the glomerulus affected
Segmental: part of the glomeruli affected
What is the most common cause of glomerulonephritis? Mechanism?
IgA Nephropathy
- Characterized by IgA deposition in the mesangium & mesangial proliferation.
Who tends to be affected by IgA nephropathy?
Most common in 2nd and 3rd decade of life with males more commonly affected
How does IgA nephropathy mediated glomerulonephritis tend to present?
- Microscopic haematuria.
- Microscopic haematuria + proteinuria
- Nephrotic syndrome
- IgA crescentic glomerulonephritis
What is post-infectious glomerulonephritis? What type of bacteria tend to cause it?
Glomerulonephritis occurring typically 10-21 days past a throat or skin infection
- Most commonly with Lancefield group A Streptococci.
How does post-infectious glomerulonephritis tend to present?
- Nephritic syndrome (high RBC in urine)
- Oedema / hypertension
How does crescentic glomerulonephritis tend to present?
++ Nephritic syndrome
Slight nephrotic syndrome
What is anti-GBM disease?
Anti-Glomerular Basement Membrane disease is an autoimmune disease where autoantibodies attack the capillaries in the kidneys &/or lungs
How does anti-GBM disease present? How is it diagnosed?
Presents as nephritic syndrome (may also have lung haemorrhage - Goodpasture’s syndrome)
- Diagnosed by detected anti-GBM antibodies in the serum & kidney
How is anti-GBM disease treated?
- aggressive immunesuppression
- steroid, plasma exchange
- cyclophosphamide (immunosuppressant)
What are some examples of non-proliferative glomerulonephritis?
Minimal Change Disease
Focal and segmental glomerulonephritis
Membranous Nephropathy
How does non-proliferative glomerulonephritis tend to present as a whole?
- Nephrotic syndromes
What are some general measures taken to treat nephrotic syndromes?
- Treat oedema: salt and fluid restriction and loop diuretics.
- Hypertension: use Renin-Angiotensin-Aldosterone-blockade.
- Reduce risk of thrombosis: Heparin or Warfarin.
- Reduce risk of infection e.g. pneumococcal vaccine.
- Treat dyslipidemia e.g. statins
What is the most common glomerulonephritis in children?
Minimal Change Disease Non-Proliferative Glomerulonephritis
How does Minimal Change Disease glomerulonephritis tend to present?
++ Nephrotic Syndrome
classic triad: proteinuria, hypoalbuminaemia, oedema, +/- hyperlipidaemia
How is Minimal Change Disease glomerulonephritis treated?
Steroids (tends to cure proteinuria):
Prednisolone – 1mg/kg for up to 16 weeks.
Once remission achieved , slow taper over 6 months.
Initial relapse treated with further steroid course.
What is the prognosis like for minimal change disease glomerulonephritis?
- Tends to be favourable, with steroid treatment the risk of end stage disease is low
What are Focal and segmental glomerulonephritis (FSGS)? Prognosis?
- Not a single disease, rather a syndrome with multiple causes.
- Pathology is focal and segmental sclerosis (scarring) in the glomerulus.
- Prognosis is poor as generally steroid resistant with high chance of progression to end stage kidney disease
How does Focal and segmental glomerulonephritis (FSGS) tend to present? Treatment options?
Presents with nephrotic syndrome
- Treat with steroids and hope for even partial remission
What is the most common cause of nephrotic syndrome in adults?
Membranous Nephropathy glomerulonephritis
- Most cases are idiopathic
Describe the pathophysiology of membranous nephropathy glomerulonephritis?
Membranous nephropathy is deposition of immune complexes on the glomerular basement membrane (GBM) with GBM thickening
What are some diagnostic markers for membranous nephropathy?
- Anti-phospholipase A2 receptor (PLA2R) antibody positive in 70% of idiopathic cases
- Thrombospondin type 1 domain containing 7A (THSD7A) in ~2%.
Treatment for membranous nephropathy glomerulonephritis? Prognosis?
- Immunosuppression and steroids
- A third resolve spontaneously, good prognosis for those whose proteinuria resolves w treatment
- 25% on dialysis at 10 years, can recur in transplants
What is the most important investigation when it comes to differentiating different types of glomerulonephritis?
- Renal biopsy
- Urine & blood tests also useful for detecting nephrotic vs. nephritic but histology confirms diagnosis often
