SFP: cystic disease, renal vessels, outflow obstruction

Question 1

Who do we see benign nephrosclerosis in?

Answer 1

Elderly patients with increased frequency/severity if they have HTN and diabetes.

Question 2

What are pathophysiologic characteristics of benign nephrosclerosis?

Answer 2

Low GFR, loss of concentrating ability, proteinuria.

Question 3

What does the kidney look like in benign nephrosclerosis?

Answer 3

Granular due to ischemic changes from a narrowed arteriole secondary to chronic HTN.

Question 4

What does chronic HTN cause histologically in blood vessels?

Answer 4

Reduplication of internal elastic lamina; can cause luminal obstruction.

Question 5

When might we see hyaline arteriolosclerosis?

Answer 5

Benign nephrosclerosis secondary to chronic HTN.

Question 6

What is malignant HTN?

Answer 6

HTN that causes immediate signs of end organ damage.

Question 7

What is seen in the renal system with malignant HTN/hypertensive emergency?

Answer 7

Renal failure/AKI, stimulation of RAAS and salt retention.

Question 8

What does the kidney look like in acute hypertensive emergency/malignant HTN?

Answer 8

“Flea-bitten” appearance from rupturing of arterioles or glomerular capillaries.

Question 9

What is seen histologically in malignant HTN?

Answer 9

Onion-skin lesions and fibrin thrombotic microangiopathy.

Question 10

What is thrombotic microangiopathy?

Answer 10

Seen in malignant HTN; fibrin thrombi in arterioles and glomeruli that block off blood flow and cause necrosis.

Question 11

What causes renal artery stenosis?

Answer 11

Atherosclerosis or fibromuscular dysplasia in young women.

Question 12

Physiologically, what does renal artery stenosis lead to?

Answer 12

Renovascular HTN with elevated renin due to decreased flow.

Question 13

What morbidities are associated with renal artery stenosis?

Answer 13

Uncontrolled HTN and chronic kidney disease.

Question 14

What will happen in unilateral renal artery stenosis?

Answer 14

Affected side will be ischemic and side without stenosis will be hypertensive.

Question 15

What is the pathophysiology of thrombotic microangiopathies?

Answer 15

Clot formation causes a high-pressure system in the vessel that impacts the flow of the blood cells. This causes the cells to shear and form schistocytes in peripheral blood.

Question 16

What is the most common cause of thrombotic microangiopathies?

Answer 16

Hemolytic uremic syndrome.

Question 17

When does hemolytic uremic syndrome often occur?

Answer 17

In the setting of GI infection (Shiga toxin from E coli) or Complement-mediated.

Question 18

What are secondary causes of thrombotic microangiopathies?

Answer 18

Pregnancy, SLE (antiphospholipid antibody), malignant HTN, GI infection.

Question 19

What defect causes thrombocytopenic purpura?

Answer 19

ADAMTS 13 that breaks down von Willebrand.

Question 20

What is the triad for presentation of thrombotic thrombocytopenia purpura?

Answer 20

1. Hemolytic anemia 2. Thrombocytopenia 3. Renal failure.

Question 21

What is cystic renal dysplasia?

Answer 21

Congenital abnormality that causes histologic abnormality; can be associated with abnormalities of lower urinary tract.

Question 22

What is seen on histology in cystic renal dysplasia?

Answer 22

Dilated tubules, primitive stroma, cartilage.

Question 23

Describe simple cysts in the kidney.

Answer 23

Common and of little consequence that are not carcinogenic; fluid is clear.

Question 24

What is acquired cystic kidney disease?

Answer 24

Occurs in end-stage renal disease aka those on dialysis or post-transplant. It will happen in the native kidney, not transplanted.

Question 25

What is the gross pathology of acquired cystic kidney disease?

Answer 25

Multiple cysts in cortex and medulla.

Question 26

How do we treat acquired cystic kidney disease?

Answer 26

The cysts may have to be removed since they increase risk for neoplasms.

Question 27

Describe the population of autosomal dominant polycystic kidney disease.

Answer 27

Seen in end stage renal disease in adults.

Question 28

What genes are associated with autosomal dominant polycystic kidney disease?

Answer 28

PKD1 and PKD2; encode for mechanosensation by cilia and calcium flux.

Question 29

What do kidneys look like in autosomal dominant polycystic kidney disease?

Answer 29

Huge kidneys with cysts everywhere.

Question 30

What 3 things are associated with autosomal dominant polycystic kidney disease?

Answer 30

Liver cysts, cerebral berry aneurysms, MVP.

Question 31

What is a major complication of autosomal dominant polycystic kidney disease?

Answer 31

Subarachnoid hemorrhage.

Question 32

What is the population of autosomal recessive polycystic kidney disease?

Answer 32

Children.

Question 33

What is the gene associated with autosomal recessive polycystic kidney disease?

Answer 33

PKHD1.

Question 34

What is the gross pathology of autosomal recessive polycystic kidney disease?

Answer 34

Enlarged smooth kidneys with radially oriented cysts.

Question 35

What causes mortality in autosomal recessive polycystic kidney disease?

Answer 35

Liver or kidney failure.

Question 36

A patient with autosomal recessive polycystic kidney disease survives infancy. What complication are they likely to develop?

Answer 36

Liver cirrhosis.

Question 37

Describe medullary sponge kidney.

Answer 37

Pretty harmless and associated with nephrolithiasis.

Question 38

What is nephronophthisis?

Answer 38

A chronic renal disease that starts in kids.

Question 39

What is the most common cause of end stage renal disease in kids and young adults?

Answer 39

Nephronophthisis-medullary cystic disease.

Question 40

What is the gross pathology of nephronophthisis?

Answer 40

Cysts at corticomedullary junction.

Question 41

What unique symptoms might be seen in nephronophthisis?

Answer 41

Polyuria and polydipsia; tubules can’t concentrate stuff, so we lose solutes, causing us to drink more water.

Question 42

Describe the pain felt with passing renal stones.

Answer 42

“Renal colic” aka flank pain radiating to the groin.

Question 43

What do renal stones predispose someone to?

Answer 43

Obstruction and infection.

Question 44

What are the most common types of renal stones?

Answer 44

Calcium oxalate and calcium phosphate.

Question 45

What is a unique cause of renal stones?

Answer 45

Struvite; associated with proteus infection.

Question 46

What causes stone formation?

Answer 46

Hypercalciuria, magnesium ammonium phosphate (struvite), gout.

Question 47

What are some acquired causes of outflow tract obstruction?

Answer 47

Stones, necrotic papillae, tumors, inflammation, pregnancy, neurogenic causes.

Question 48

What is the pathophysiologic result of outflow tract obstruction?

Answer 48

Hydronephrosis aka dilation of renal pelvis and calyces.

Question 49

What can happen to the fluid in outflow tract obstruction?

Answer 49

When it becomes stagnant it can become infected.