Glomerulonephritis Flashcards
(54 cards)
What are the main kinds of glomerular disease?
Diabetic Nephropathy
Glomerulonephritis (GN)
Amyloid/ Light Chain Nephropathy
Transplant Glomerulopathy
What are the two most common causes of end stage renal disease?
- Diabetes
- Chronic glomerulonephritis
What is glomerulonephritis?
An immune mediated disease of the kidneys affecting the glomeruli causing secondary tubulointerstitial damage
What are podocytes?
Cells that spread out around capillaries in branches, forming protein bridges (actin and myosin) between these branches to provide strong mechanical strength for the capillaries
What are mesangial cells?
Cells found between groups of capillaries that work in tandem with the glomerular basement membrane:
They act like smooth muscle cells and can cause vasoconstriction
They have immune function, releasing cytokines
What does the glomerular basement membrane consist of?
It is acellular and consists of collagen and protein
Which components of the glomerulus are injured in prolfierative glomerulonephritis?
Mesangial cells
Endothelial cells
Why does haematuria occur in proliferative GN?
Mesangial and endothelial cells are exposed to blood, so injury causes red cells in urine and a proliferative lesion and activation of the inflammatory cascade
This causes a nephritic syndrome
What does injury to podocytes result in?
Non-proliferative lesion and protein in urine
There is no activation of the inflammatory cascade since the podocytes are not exposed to blood
This causes nephrotic syndrome
What colour is urine typically in glomerulonephritis?
‘Smoky’, ‘rusty’ or coca-cola coloured
How should urine be examined if GN suspected and what would be expected?
Urinalysis: haematuria, proteinuria
Urine microsopy: RBC (dysmorphic), RBC & granular casts, lipiduria
Urine Protein: creatinine Ratio
24 hour urine - quantify proteinuria
How is haematuria normally picked up in glomerulonephritis?
Dipstick test - the haematuria is painless
How is proteinuria judged?
Microalbuminuria (30-300mg albuminuria/day)
Asymptomatic proteinuria (< 1 g/day)
Heavy proteinuria (1-3 g/day)
Nephrotic syndrome (> 3 g/day))
What is the usual diagnosis if red cell casts seen on microscopy of urine?
Indicates active, aggressive proliferative lesion
How does glomerulonephritis present?
Oedema
Hypoalbuminuria
Decresed renal function
Hypertension
Haematuria
Frothy urine
Why does hypertension occur in glomerulonephritis?
Fluid retention
Proliferative lesion causing increased renin secretion
What are the three indicators of nephrotic syndrome?
Oedema
Hypoalbuminuria
Proteinuria
Why does impaired immunity occur in nephrotic syndrome?
Opsonising antibodies are leaked out into urine
What is a complication of nephrotic syndrome that would make a patient present with unilateral loin pain and haematuria for the first time, and why?
Renal vein thrombosis
Hypoalbuminuria can change liver function, causing increased production of clotting and fibrotic factors
What are the features of nephrotic syndrome?
Proteinuria > 3 g/day (mostly albumin, also globulins)
Hypoalbuminaemia (<30)
Oedema
Hypercholesterolaemia
Usually normal renal function
What are the features of nephritic syndrome?
Acute Renal Failure
Oliguria
Oedema/ Fluid retention
Hypertension
Active urinary sediment: RBC’s, RBC and granular casts
What are the complications of nephrotic syndrome?
Infections
Renal vein thrombosis
Pulmonary emboli
Volume depletion: often due to overuse of ACEi, may lead to pre-renal AKI
Vit D deficiency
Subclinical hypothyroidism
What are the four components of histological classification of glomerulonephritis?
Proliferative/non-proliferative
Focal/diffuse (< or > 50% glomeruli affected)
Global/segmental (all or part glomerulus affected)
Crescentic
What does ‘crescentic’ mean on histological description of glomerulonephritis?
Presence of crescents: cells burst into Bowman’s space and form crescents around the glomerulus, causing ischaemia and death of the glomerulus
