Glomerular disease pathology Flashcards
What is a podocyte?
glomerular epithelial cell with foot processes
cells in bowmans capsule that wrap around capillaries of the glomerulus
What proteins are not filtered at the glomerulus?
bigger or equal to albumin + ig
3 parts of filter barrier membrane at glomerulus
endothelial cell cytoplasm
basal lamina
podocyte
What are mesangial cells?
“tree-like” group of cells which support capillaries
What is found in the efferent arteriole?
blood cells, some fluid, albumin+larger proteins and antibodies
What is glomerulonephritis?
disease of the glomerulus which can be inflammatory or non inflammatory
Difference between primary and secondary glomerulonephritis
primary - only affects glomerulus
secondary - other parts of body affected eg SLE
Aetiology of glomerulonephritis
Ig deposition stuck in filter
can be no Ig deposition eg diabetic glomerular disease
4 common presentations/signs of glomerulonephritis
haematuria
heavy proteinuria (nephrotic syndrome)
slowly increasing proteinuria
acute renal failure - rising creatinine
4 causes of haematuria
UTI
Urinary tract stone
urinary tract tumour
glomerulonephritis - rare
What should always be checked before a renal biopsy?
clotting screen
What happens in mesangial proliferative glomerulonephritis?
IgA deposition in mesangial cells causing proliferation which leads to increased matrix production
prognosis of mesangial proliferative glomerulonephritis
most resolve and self limiting
small % - chronic renal failure due to continued deposition of matrix
If serum albumin is low but urine albumin high what does this suggest?
leaky glomerular filter
membranous glomerulonephritis
What immunoglobulin is related to membranous glomerulonephritis?
IgG
What happens to the glomerular basement membrane in membranous glomerulonephritis ?
thickened
spikes of new basement membrane matrix
What does the IgG do in membranous glomerulonephritis ?
not filtered and lodges between basal lamina and podicyte
activates complement to punch holes in filter - leaky
Consequence of IgG activating complement
albumin now in urine - nephrotic syndrome
Prognosis of membranous glomerulonephritis
1/4 - chronic renal failure in 10 years
can have underlying malignancy
What happens in diabetic nephropathy?
small, compressed capillary lumen due to increased mesangial matrix
reduced blood flow - atherosclerosis
thickened capillary wall leaks albumin
What are the nodules of mesangial matrix in diabetic nephropathy called?
Kimmelsteil - Wilson lesion
What Ig is present in diabetic nephropathy?
none
What 2 factors means inevitable decline in diabetic nephropathy?
continued poor glycaemic control
established diabetic nephropathy
What does rapidly rising creatinine signify?
acute renal failure
What is crescentic glomerular nephritis?
cellular proliferation and influx of macrophages causing a crescent tuft and crushed glomerulus leading to inflammation and scarring
What is granulomatosis with polyangitis?
a form of vasculitis which affects vessels in kidneys, nose and lungs
What is ANCA?
antibody indicating vasculitis
Is ANCA deposited in the kidney?
no
What are ANCA antibodies directed towards?
enzymes in primary granules of neutrophils
What do ANCA antibodies lead to?
produce tissue damage via interactions with primed neutrophils and endothelial cells
Prognosis of granulomatosis with polyangitis
fatal - 6 months if untreated
75% remission with cyclophosphamide
