L7: Kidney disease and renal failure Flashcards
3 categorises of kidney disease
pre-renal
intrinsic
post-renal
what does post-renal lead to in the kidney
hydronephrosis
can nephrons regenerate
NO
urinary excretion rate=
filtration rate - reabsorption rate + secretion rate
3 layers of glomerular capillaries
endothelium
basement membrane
podocytes
how does glomerular filtrate move through the podocytes
through slit pores between them
apart from the basement membrane what can also stop protein passage
the podocytes also have a negative charge
main consequence of nephrotic syndrome
protein loss
4 features of nephrotic syndrome
peripheral oedema
proteinuria
hypoalbuminaemia
hypercholesterolaemia
what biochemical markers are needed for a nephrotic syndrome diagnosis
proteinuria
hypoalbuminaemia
what is nephrotic range proteinuria almost always due to
glomerular disease
what are most nephrotic diseases associated with
podocyte injury and loss of anionic charge in the capillary wall
what 2 things does proteinuria result from
loss of charge and size selectivity
2 mechanisms for oedema in nephrotic syndrome
overfill and underfill mechanism
underfill mechanism=
- reduced oncotic pressure means fluid moves into ECF
- reduced plasma volume activates sodium and water reabsorption
what is the overfill mechanism
a defect in sodium excretion increases blood volume increasing hydrostatic pressure moving fluid into ECF
3 primary causes of nephrotic disease
minimal change disease
focal segmental glomerulosclerosis
membranous GN
what is minimal change disease
- effacement of pedicles causing protein leakage
- little chronic damage
treatment of minimal change disease
steroids
what is segmental glomerulosclerosis
- segmental scarring lesions within glomerular tuft
- bad prognosis (hard to treat)
membranous nephropathy
electron dense immune deposits on basement membrane creating holes
in whom are secondary causes of nephrotic disease more common
adults
in whom are primary causes of nephrotic disease more common
children
name 4 secondary causes of nephrotic disease
diabetic nephropathy
amyloidosis
chronic viral infection
cancer