Renal Path II

Question 1

What is the presentation of acute pyelonephritis?

Answer 1

fever, flank pain, costovertebral angle tenderness
neutrophils
WBCs in urine, WBC casts
**often ascending UTI like E coli

Question 2

What does a CT show w/ acute pyelonephritis?

Answer 2

striated parenchymal enhancement

Question 3

What are risk factors for acute pyelonephritis?

Answer 3

indwelling urinary catheter
obstruction
vesicoureteral reflux
diabetes
pregnancy

Question 4

When do you see thyroidization of the kidney?

Answer 4

Chronic pyelonephritis

get eosinophilic casts

Question 5

What is drug-induced interstitial nephritis?

Answer 5

give drugs that act as haptens and induce hypersensitivity 1-2 weeks later
get pyuria and azotemia

Question 6

What are the presenting symptoms of drug-induced interstitial nephritis? Treatment?

Answer 6

fever
rash
eosinophilia
azotemia

Treat w/ 1-2 weeks corticosteroids

Question 7

Which drugs cause drug-induced interstitial nephritis?

Answer 7

NSAIDs
Diuretics
Penicillin Derivatives
PPI
sulfonamides
rifampin
allopurinol
indinavir
mesalamine

Question 8

What is diffuse cortical necrosis?

Answer 8

cortical infarction of both kidneys via combo of vasospasm and DIC
seen in patients who experience obstetric catastrophes or septic shock or ARDs.

Question 9

What are the 2 mechanisms of injury in acute tubular necrosis? Key finding?

Answer 9

ischemic and nephrotoxic

see granular muddy brown casts

Question 10

What are the 3 phases of acute tubular necrosis?

Answer 10

1. inciting event
2. maintenance phase—oliguric, 1-3 weeks, risk of hyperkalemia, metabolic acidosis, uremia
3. recovery phase-polyuric, BUN and serum creatinine fall, risk of hypokalemia

Question 11

How does ischemia cause acute tubular necrosis? Which parts of the kidney are most susceptible to injury?

Answer 11

renal tubular cells slough into lumen

PCT and thick ascending limb are super suspectible

Question 12

What are some toxic substances that could cause nephrotoxic acute tubular necrosis?

Answer 12

aminoglycosides
radiocontrast dye
lead
cisplatin
crush injury (myoglobinuria)

Question 13

What do you see in renal papillary necrosis?

Answer 13

sloughing off of necrotic renal papillae
gross hematuria and proteinuria
**triggered by recent infection or immune stimulus

Question 14

Which conditions is renal papillary necrosis associated with?

Answer 14

SAAD papa
Sickle Cell
Acute pyelonephritis
analgesics (NSAIDs)
Diabetes

Question 15

What defines acute renal failure?

Answer 15

decline in renal fcn w/ increase in creatinine and BUN

Question 16

Describe prerenal azotemia.

Answer 16

BUN/CR>20 (BUN reabsorbed relatively more)
decreased renal blood flow
decreased FENa 500

Question 17

Describe intrinsic renal failure.

Answer 17

BUN/Creatinine ratio 2%

Urine osmolality

Question 18

Describe postrenal azotemia.

Answer 18

caused by outflow obstruction like BPH or kidney stone
only get this w/ bilateral obstruction
FENa

Question 19

What are the consequences of renal failure?

Answer 19

MAD HUNGER
Metabolic Acidosis
Dyslipidemia
Hyperkalemia
Uremia (increased BUN)
Na+/H2O retention--pulmonary edema, heart failure
Growth retardation
EPO failure (anemia)
Renal osteodystrophy from decreased VIT D activation

Question 20

What are the consequences of uremia in renal failure?

Answer 20

nausea and anorexia
pericarditis
asterixis
encephalopathy
platelet dysfunction

Question 21

Describe what the deal is with renal osteodystrophy.

Answer 21

failure of Vit D hydroxylation, hypocalcemia and hyperphosphatemia.
hyperparathyroidism.
Causes subperiosteal thinning of bones
supplement w/ Vit D and Ca++