Flashcards in Renal Path II Deck (21):
What is the presentation of acute pyelonephritis?
fever, flank pain, costovertebral angle tenderness
WBCs in urine, WBC casts
**often ascending UTI like E coli
What does a CT show w/ acute pyelonephritis?
striated parenchymal enhancement
What are risk factors for acute pyelonephritis?
indwelling urinary catheter
When do you see thyroidization of the kidney?
get eosinophilic casts
What is drug-induced interstitial nephritis?
give drugs that act as haptens and induce hypersensitivity 1-2 weeks later
get pyuria and azotemia
What are the presenting symptoms of drug-induced interstitial nephritis? Treatment?
Treat w/ 1-2 weeks corticosteroids
Which drugs cause drug-induced interstitial nephritis?
What is diffuse cortical necrosis?
cortical infarction of both kidneys via combo of vasospasm and DIC
seen in patients who experience obstetric catastrophes or septic shock or ARDs.
What are the 2 mechanisms of injury in acute tubular necrosis? Key finding?
ischemic and nephrotoxic
see granular muddy brown casts
What are the 3 phases of acute tubular necrosis?
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
How does ischemia cause acute tubular necrosis? Which parts of the kidney are most susceptible to injury?
renal tubular cells slough into lumen
PCT and thick ascending limb are super suspectible
What are some toxic substances that could cause nephrotoxic acute tubular necrosis?
crush injury (myoglobinuria)
What do you see in renal papillary necrosis?
sloughing off of necrotic renal papillae
gross hematuria and proteinuria
**triggered by recent infection or immune stimulus
Which conditions is renal papillary necrosis associated with?
What defines acute renal failure?
decline in renal fcn w/ increase in creatinine and BUN
Describe prerenal azotemia.
BUN/CR>20 (BUN reabsorbed relatively more)
decreased renal blood flow
decreased FENa 500
Describe intrinsic renal failure.
BUN/Creatinine ratio 2%
Describe postrenal azotemia.
caused by outflow obstruction like BPH or kidney stone
only get this w/ bilateral obstruction
What are the consequences of renal failure?
Uremia (increased BUN)
Na+/H2O retention--pulmonary edema, heart failure
EPO failure (anemia)
Renal osteodystrophy from decreased VIT D activation
What are the consequences of uremia in renal failure?
nausea and anorexia