Week 10 - Glomerular pathology Flashcards
What urine abnormality is dominant in nephritic syndrome?
-Haematuria
What urine abnormality is dominant in nephrotic syndrome?
-Proteinuria
Which group of glomerular pathology leads to hypoalbuminaemia?
-Nephrotic syndrome
Why do you get oedema in nephrotic syndrome?
- Loss of albumin in the urine results in a decreased oncotic pressure in the capillaries
- ECF which is pushed into the interstitium by hydrostatic pressure at the proximal capillary is not drawn back and oedema occurs
Why does hyperlipidaemia occur in nephrotic syndrome?
- Due to hypoalbuminaemia
- Liver tries to compensate by increasing protien production however there is a side effect of increasing lipid production
Which part of the glomerulus is affected in nephritic syndrome?
-Problems with epithelia
Which part of the glomerulus is affected in nephrotic syndrome?
-Podocyte damage
What are the 3 common primary causes of nephrotic syndrome?
- Minimal change glomerulonephritis
- Focal Segmental Glomerulosclerosis
- Membranous glomerulonephritis
What is the most common secondary cause of nephrotic syndrome?
-Diabetes mellitus
When does minimal change glomerulonephritis present?
- In childhood/adolescence
- Incidence decreases with age
What is the primary urine abnormality in minimal change glomerulonephritis?
-Proteinuria
Does minimal change glomerulonephritis progress to renal failure?
-Not usually
What is the cause of minimal change glomerulonephritis?
-Destruction of podocytes via an unknown mechanism
What are the differences between minimal change glomerulonephritis and focal segmental glomeruloslcerosis?
- FGS occurs in adults
- FGS is less responsive to setroids
- FGS progresses to renal failure due to scarring
What is the cause of membranous glomerulonephritis?
-Immune complex formation which become caught in the filter and cause a thickened glomerular basement membrane
What is thought to be the cause of immune complex formation in membranous glomerulonephritis?
-Phospholipase on podocytes causing an autoimmune response by IgG
What is the rule of 3rds in membranous glomerulonephritis?
- 3rd patients remit
- 3rd patients ill but stable
- 3rd patients enter renal failure
What is thought to be a secondary cause of membranous glomerulonephritis?
-Lymphoma
How does diabetes mellitus lead to nephrotic syndrome?
-Microvascular damage leads to progressive proteinuria and progressive renal failure with mesangial sclerosis
What is the most common cause of glomerulonephritis?
-IgA nephropathy
Name 2 hereditary diseases which cause nephritic syndrome
- Alport
- Thin glomerular basement membrane disease
When does IgA nephropathy present?
-At any age
How does IgA nephropathy present?
-Usually with macro/microscopic haematuria
What is IgA nephropathy associated with mucosal infections?
-During infection there is an increased production of IgA which increases blockage in the glomerulus
Does IgA nephropathy progress to renal failure?
-Significant portion
What is the pathophysiology of IgA nephropathy?
- IgA forms immune complexes which become deposited in the mesangium
- Mesangial damage results in proliferation of mesangial cells and excessive matrix production
Why does alports disease cause nephritic syndrome?
-Abnormal type 4 collagen in BM
What clinical problem is associated with alports disease?
-Deafness
Which hereditary nephritic syndrome progresses to renal failure?
- Alports
- Thin basement membrane disease does not
What is good-pasture syndrome? What is its cause? How is it treated?
- Acute onset of severe nephritic syndrome which is rapidly progressive to renal failure (within 24 hours)
- Caused by autoantibody to T4 collagen in glomerular BM
- Treated with immunosuppressants and plasmophoresis if caught early
What is vasculitis and how does it cause nephritic syndrome?
-Group of systemic disorders which are associated with ANCA causing rapid progressive glomerulonephritis
What are the two types of pathology that can occur at the glomerulus?
- The filter can block -> nephritic syndrome
- The filter can leak -> nephrotic syndrome
