Exam 2 Vascular issues of kidneys Flashcards
What is benign nephrosclerosis
a process in which there is hyaline sclerosis of the renal arterioles and small arteries. can lead to HTN
What do kidneys look like in someone with nephrosclerosis
cotex has a grainy look. decreased size
medial hypertrophy with narrowed lumen
collagen in bowlmas space
What are signs of nephrosclerosis
moderate dec in renal blood flow, GFR is normal or slightly reduced
there is mild proteniuria
multi focal ischemia of the kidney parenchyma
what are the demographics of benign nephrosclerosis
older age and african american
What renal disease is assoc with malignant HTN
accelerated nephrosclerosis- small vessel disease
severe changes
What is the definition of malignant arteriolosclerosis/ nephrosclerosis
renal vascular disorder, exhibiting injury, associated with malignant or accelerated HTN
what are the pathologic effects from malignant arterosclerosis
ischemic kidneys and extremely high levels of renin
what is the pathogenesis of malignant HTN effects on kidneys begining with renal vascular disease
increased permeability of small vessels endothelial ireeversible injury focal vascular cell death platelet deposition(thrombosis) fibrinoid necrosis of arterioles and small arteries hyperplastic arterolitis
What are signs of malignant HTN
papilledema, retinal hemorrhage, encephalopathy, CV abnormalities, renal failure
What do you do to Tx malignant HTN
aggressive anti HTN
how many people with malignant nephrosclerosis regain renal function
50%
What do kidneys look like from malignant HTN (gross) not microscopic
flea bitten appearance of renal hemorrhages
What is renal artery stenosis/large vessel disease
athermatous plaque occlusion at origin of artery
or fibromuscular dysplasia of the renal artery
what type of renal artery stenosis is most common in men
atheromatous plaque occlusion
what type of renal artery stenosis is most common in women
fibromuscular dysplasia of renal arter
mainly in the media portion of artery
What is important about the Tx for large vessel disease, renal artery stenosis
curable with surgery
is renal artery stenosis more b/l or unilateral
uni
what is the demographic for renal artery stenosis
younger age group of women
what does fibromuscular dysplasia of renal artery look like on contrast CT
string of beads
Where does angiotensin II work systemically
cardiac and vascular hypertrophy
systemic vasoconstriction, increased blood volume, renal sodium and fluid retention(from adolsterone and ADH too)
what do the kidneys look like grossly in renal a stenosis
reduced in size
diffuse ischemic atrophy
What is the clinical presentation of large a disease/renal artery stenosis
looks like essential HTN
bruit of affected kidneys
elevated plasma renin
respond well to ACE inhibitor
what is used to Dx renal artery stenosis
renal scans, IV pyelography
what is the post surgery cure rate for renal artery stenosis
70-80%
What are the two main types of thrombotic microangiopathies and what does this mean
hemolytic uremic syndrome and thrombotic thrombocytopenic purpura
diverse insults leading to excessive activation of platelets which deposit thrombi in capillaries and arterioles in various tissue beds
What are seen in peripheral blood smears in thombotic microangiopathies
schistocytes which are fragmented RBCs
What are common toxins that trigger endothelial injury
bacterial toxins, cytokines, viruses, certain medications
anti-endothelial Ab
What is the pathogenesis of typical HUS
associated with diarrhea from consuming contaminated food with shiga like toxin E coli O157:H7
mostly in children
leads to platelet activation and vasoconstriction
describe atypical HUS
non-epidemic, non-diarrheal
can he from inherited mutations of complement protein regulators (Factor H and I)
multiple insults to endothelium
antiphospholipid syndrome, pregnancy associated, systemic sclerosis and malignant HTN, chemo and kidney irradiation
what is the most common way to acquire atypical HUs in adults
chemotherapeutic agents and immunosuppressive drugs
What is associated with deficiency in ADAMS13 protease and what is the normal function of this protease
associated with TTP
protease regulates function on vWF (inhibitory regulation) so when deficient constitutively activated
what is a major sign of TTP and what age group is it seen most in
prominent neurologic involvement, presents as adults younger than 40
What is the mechanism of destruction with atypical HUs
platelet activaiton, thombosis in microvscular beds leading to increased endothelin production, vasoconstriction and hypoperfusion of tissues
What would the kidney look like during acute active disease of HUS or TTP
thick capillary walls, subendothelial deposits of fibrin, disruption mesangial matrix
What thrombotic microangiopathies can present with chronic disease? what does it look like
atypical HUS and TTP
scarring of renal Cx, split BM of glomeruli
arteries wall thickening (onion skinning)
persistent hypoperfusion–> HTN
What is clinical presentation of typical HUS
influenza like diarrhea, sudden bleeding like hematemesis and melena, oliguria, hematuia, microangiopathic hemolytic anemia, thrombocytopenia and sometimes neuro Sx
What is the most common type of C’ deficiency seen in atypical HUS
deficient Factor H
What is the clinical presentation of TTP
fever and neuro symptoms, microangiopathic hemolytic anemia, thrombocytopenia, renal failure in 50%
What does microangiopathic hemolytic anemia look like in peripheral blood smear
fragmented RBC, many immature RBC
What has worse prognosis typical or atypical HUS
atypical
What type of microangiopathy do you do plasmapheresis with
TTP successful in >80%
Is artherosclerotic ischemic renal disease unilateral or bilateral
b/l
What population is arteroembolic renal disease more likely in
older patients with severe atherosclerosis
Why are kidneys at high risk of damage from emboli
only have 1 main artery bringing in blood supply
what are underlying processes that can lead to arteroembolic renal disease
mural thrombosis from left side of the hear, vegetative endocarditis, aortic aneurysms, aortic atherosclerosis
what is clinical signs of sickle cell nephropathy
hematuria, hyposthenuria
patchy papillary necrosis
30% have proteinuria, sub-nephrotic range
when does diffuse cortical necrosis occur
after obstetric emergencies, aburtption placenta, septic shock or extensive surgeries
what does diffuse cortical necrosis look like
massive ischemic necrosis limited to cortex
intravascular thrombosis focally
if diffuse cortical necrosis is b/l what is prognosis
fatal
what do renal infarcts look like microscopically and clinically
white anemic in fats, sharply demarcated
ringed by zone of hyperemia
usually clinically silent, somtimes Tender CVA with showers of RBC in urine
can cause HTN
