Renal Pathology 5

Question 1

what is nephrosclerosis?

Answer 1

sclerosis of the renal arterioles and small arteries

Question 2

what is nephrosclerosis strongly associated with?

Answer 2

hypertension

Question 3

how do the kidney appear in cases of nephrosclerosis?

Answer 3

the kidneys are either normal or moderately reduced in size; the cortical surfaces have a fine, even granularity

Question 4

hypertension secondary to renal artery stenosis is due to what?

Answer 4

increased production of renin from the ischemic kidney

Question 5

in cases of renal artery stenosis, what class of drug would you use to treat the resultant elevation in renin with?

Answer 5

ARBs- aka drugs that block angiotensin II

Question 6

what is fibromuscular dysplasia?

Answer 6

a focal irregular thickening in medium and large muscular arteries including renal, carotid arteries

Question 7

what demographic of patient is FMD more commonly seen?

Answer 7

women in their 3rd-4th decade of life

Question 8

what can FMD lead to?

Answer 8

aneurysms, which can then rupture

Question 9

what are the two forms of thrombotic microangiopathy we discussed?

Answer 9

thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS)

Question 10

what is typical HUS?

Answer 10

most frequently associated with the consumption of food contaminated by e. coli O157:H7

Question 11

who is most at risk for typical HUS?

Answer 11

children and older adults

Question 12

what are the signs and symptoms of typical HUS?

Answer 12

following an episode of diarrhea, increased bleeding tendencies, renal failure, microangiopathic hemolytic anemia, thrombocytopenia, and neurologic changes

Question 13

more than half of those affected with atypical HUS have an inherited deficiency in what?

Answer 13

complement regulatory proteins, such as factor H, factor I, and CD46

Question 14

if a patient has atypical HUS that is not caused by an inherited deficiency in complement regulatory proteins, what might they have instead?

Answer 14

antiphospholipid syndrome (either primary or secondary to lupus), complications of pregnancy or postpartum, systemic sclerosis, malignant hypertension, chemotherapeutic and immunosuppressive agents, or irradiation of the kidney

Question 15

what are 5 examples of chemotherapeutic and immunosuppressive drugs that could lead to atypical HUS?

Answer 15

mitomycin, cyclosporine, cisplatin, gemcitabine, and antagonists of VEGF

Question 16

how is TTP usually manifested?

Answer 16

pentad of symptoms: fever, neurologic symptoms, microangiopathic hemolytic anemia, thrombocytopenia, and renal failure

Question 17

what is the initiating event of TTP?

Answer 17

platelet aggregation induced by very large multimers of vWF, which accumulate due to a deficiency of ADAMTS13

Question 18

why might a patient have a deficiency in ADAMTS13?

Answer 18

they may have inhibitory autoantibodies, or they may have inherited an inactivating mutation in ADAMTS13

Question 19

how do you treat TTP?

Answer 19

plasma exchange, which removes autoantibodies and provides functional ADAMTS13

Question 20

what is the morphological appearance of the kidney in cases of TTP?

Answer 20

there is diffuse cortical necrosis. the pale ischemic necrotic areas are confined to the cortex

Question 21

what are the histologic features of a kidney with TTP?

Answer 21

acute ischemic infarction; fibrin stain showing thrombi in the glomerular capillaries

Question 22

at what vertebral level do the renal arteries arise from the abdominal aorta?

Answer 22

L1

Question 23

how is bilateral renal artery disease usually diagnosed?

Answer 23

arteriography

Question 24

what does bilateral renal artery disease usually cause?

Answer 24

chronic ischemia with renal insufficiency in older individuals sometimes in the absence of HTN

Question 25

why is it so important to recognize and diagnose bilateral renal artery disease?

Answer 25

surgical revascularization can prevent further decline in renal function

Question 26

what is atheroembolic renal disease?

Answer 26

when there is embolization of fragments of atheromatous plaques from the aorta or renal artery into intrarenal vessels

Question 27

what demographic of patients is atheroembolic renal disease most likely?

Answer 27

in older adults with severe atherosclerosis, especially after surgery on the abdominal aorta, aortography, or intra-aortic cannulization

Question 28

what are some other sources/reasons from renal emboli?

Answer 28

mitral stenosis with a fib, MI with mural thrombosis, and vegetative endocarditis

Question 29

what is sickle cell nephropathy?

Answer 29

when sickle cell disease/trait leads to a variety of alterations in renal morphology and function

Question 30

what are the most common abnormalities seen in sickle cell nephropathy?

Answer 30

hematuria and a diminished concentrating ability; patchy papillary necrosis; proteinuria