Flashcards in Session 9 - Glomerular damage Deck (48)
What are the main foci of kidney disease?
• Vascular supply
What is a primary glomerular injury?
• One which just effects the glomerulus
What is a secondary glomerula injury?
• A systemic illness which happens to effect the glomerulus
What are the four main sites of glomerular injury?
○ Anything that effects podocytes/podocyte side of glomerular basement membrane
• Within glomerula basement membrane
○ Inside the basement membrane
○ Supporting capillary loop
Why can the nephron be termed a "functional unit"
• Same blood supply to glomerulus and nephron
○ Thus, ischaemic disease in glomerulus reduces blood supply to nephron, causing damage
What are the two main pathologies of the glomerulus?
• It can become blocked
○ "Renal Failure"
○ Decreased GFR
• It can leak
○ One, other or both
What is proteinuria?
• Presence of excess serum proteins in the urine (<3.5g filtered every 24 hours)
What does proteinuria indicate?
• Podocyte damage, causing fenestration to widen and causing protein to be leaked when it would normally be filtered
Less severe nephrotic syndrome
What is nephrotic syndrome?
• More than 3.5g of protein lost in urine per day
Soon becomes hypoalbuminaemia
How does the body respond to hypoalbuminaemia as a result of nephrotic syndrome?
• Liver starts to pump out more albumin, along with more cholesterol!
What is nephritic syndrome?
• Glomerulus is blocked
• GFR drops
• Creatinine increases
• Haematuria (glomerulus blood vessels ruptured)
What are the four main areas in the glomerula capillary loop where damage can occur?
• With GBM
What is the difference between primary and secondary kidney disease?
• Primary kidney disease - Pathology soley affecting kidney
• Secondary kidney disease - Systemic disease which affects kidney
What is the likely site of injury in proteinuria/nephrotic syndrome?
• Podocyte/subepithelial damage
Give three primary causes of proteinuria/nephrotic syndrome
• Minimal change glomerulonephritis
• Focal segmental glomerulosclerosis
• Membranous glomerulonephritis
Give two common secondary cuases of proteinuria/nephrotic syndrome
• Diabetes mellitus
When does minimal change glomerulnephritis occur?
• Occurs in childhood/adolescence
• Incidence reduces with increasing age
What are the symptoms of glomerulonephritis?
• Heavy proteinuria or nephrotic syndrome
• Responds to steroids
• Usually no progression to renal failure
Why does minimal change glomerulonephritis occur?
• Podocytes destroyed, loss of filtration slits
What is the pathogenesis of minimal change glomerulonephritis?
• Unknown circulating factor damaging podocytes
• No immune complex deposition
Why is minimal change glomerulonephritis called thus?
• Normal golmeurli under a light microscope
How can you detect minimal change glomerulonephritis?
• Electron microscope, damage to podocytes evident
What is Focal segmental glomerulosclerosis
• Nephrotic syndrome which effects adults
• Steroids minimally effective
What does a patient with focal segmental glomerulosclerosis normal present with?
• Massive proteinuria
• Renal failure
Why is it called focal segmental glomerula sclerosis?
• Focal - Involving less than 50% of glomeruli on light microscopy
• Segmental - Involving part of the glomerular tuft
• Sclerosis - Scarring
What is the main pathology of Focal segmental glomerulosclerosis?
• Damage to glomerulus causing scarring
• Circulating factor damages podocytes
• Progressive renal failure
What causes Focal segmental glomerular nephritis?
• A circulating factor
What is membranous glomerulonephritis?
Commonest cause of nephrotic syndrome in adults
Immune complex deposits
Capillary loop thick
Basement membrane specley
What causes membranous glomerulonephritis?
• Autoimmune response to podocytes
• Immune complex deposits (IgG)
○ May also be secondary, as often associated with diseases such as lymphoma