acute kidney injury

Question 1

what are the 3 classifications of acute kidney injury (AKI)?

Answer 1

prerenal, intrinsic, postrenal

Question 2

prerenal is the most common cause of AKI, and is caused by what?

Answer 2

hypoperfusion leading to lower GFR

low CO = low effective renal blood flow

Question 3

what lab result will you see in prerenal dz?

Answer 3

BUN:Crea >20:1
hyaline casts
concentrated urine

Question 4

what are 3 types of intrinsic renal dz? (accounting for up to 50% of AKI)

Answer 4

acute tubular necrosis
acute interstitial nephritis
glomerulonephritis

Question 5

causes of ATN?

Answer 5

toxic or ischemic injury (prolonged pre-renal state), sepsis, vascular occlusion
85% of intrinsic renal dz.
AMINOGLYCOSIDES - exogenous (external)
MYOGLOBIN - endogenous (internal)

Question 6

causes of AIN?

Answer 6

INFLAMMATION! of renal tubules and interstitium
usually caused by DRUGS
10-15% of intrinsic renal dz.

Question 7

what drugs cause AIN?

Answer 7

PCN, cephalosporins, sulfas, NSAIDS

Question 8

what causes glomerulonephritis?

Answer 8

immune complex deposition
anti-GBM associated/goodpasture
pauci-immune (ANCA-related): wegener, curg-strauss

Question 9

s/s of ATN?

Answer 9

nausea/vomiting
malaise
BP changes

Question 10

s/s AIN?

Answer 10

classic triad:
FEVER
transient maculopapular rash
arthralgies

Question 11

diagnostic data ATN

Answer 11

-abrupt decrease GFR
MUDDY BROWN CASTS
BUN:Crea < 20:1

Question 12

tx for ATN?

Answer 12

• loop diuretics
• protein restriction
• dialysis

Question 13

diagnostic data AIN?

Answer 13

• sterile pyuria (wbc in urine w/out bact)
• elevate crea
• eosinophilia
• WHITE CELL CASTS

Question 14

tx for AIN?

Answer 14

supportive/removal of causative agent

corticosteriods if persists (prednisone)