diabetic nephropathy Flashcards
what is diabetic nephropathy
kidney damage caused by type 1 and type 2 diabetes
diabetic nephropathy is the leading cause of
end stage renal failure in the UK
in diabetes mellitus there is
excess glucose in the blood so when the blood is filtered in the kidneys some of it spills into the urine (glycosuria), also excess glucose in the blood starts to bind to proteins by a process called non-enzymatic glycation, because glucose gets through the endothelium to the basement membrane the process of non-enzymatic glycation can occur at the basement membrane which causes it too thicken, this process particularly affects the efferent arteriole causing it to narrow in a process called hyaline arteriosclerosis
this creates an obstruction making it
difficult for blood to leave the glomerulus which increases pressure within the glomerulus which increases the glomerular filtration rate causing the afferent arteriole to dilate which further increases the pressure within the glomerulus
the increase pressure within the glomerulus
increases the glomerular filtration rate causing hyper filtration which is the first even in diabetic nephropathy
in response to the hyper-filtration the
mesangial cells secrete more structural metrix resulting in the formation of kimmlestein wilson nodules (which are tiny balls of protein)
thickening of the glomerular basement membrane
counter-intuitively increases its permeability which allows proteins to enter the filtrate because the space between the slit processes of podocytes increases
eventually these changes damage
the glomerulus so much that it can no longer filter blood properly so the glomerular filtration rate falls
initially during the hyper-filtration phase
there are no overt symptoms but over time the GFR falls
because there are no overt symptoms initially of diabetic nephropathy it is
extremely important to screen the urine of people with diabetes for proteinuria
proteinuria is measured from the
urinary albumin excretion rate
normal albumin levels
less than 30mg/ day
microalbuminuria
30-300mg/day
macroalbuminuria
more than 300mg/day
diabetic neprhopathy is a
progressive complications which can be slowed down but not completely stopped
