Flashcards in Renal function test Deck (23):
Ratio BUN: Cr > 20 vs <20 suggest what?*******
can this be used as a dx?
>20: pre renal injury (dehydration, volume depletion)
<20: intra-renal injury (something actually happening inside kidney)
should not rely soley for dx, but can be helpful in directing work-up
what does muddy brown cast indicate in microscopy*******
its granular: Acute Tubular Necrosis
pyelonephritis, interstitial nephritis, post-strep glomerular nephritis
Eosinophils in microscopy
AIN (acute/allergic interstitial nephritis), contrast
what will you see in Multiple myloma microscopy
sometimes light chains will not be picked up on urinalysis.
No protein on dipstick, proteinuria on UPC ratio
Rhabdomyolysis: + blood, but NO RBC
Myoglobin, not hemoglobin in blood
If you suspect kidney stones, what type of test would you want? **
Benefits of using CT scan over ultrasound****
to dx kidney stones, nephro or urolithiasis
better quality use for obese patients
Can delineation of lesion better than ultrasound
necessary for angiography (to see blood vessels)
what are the 3 categories for Acute kidney injury? main causes?******
Pre-renal: dehydration, volume depletion
intra-renal (glomerulonephritis, ATN, acute interstitial nephritis(AIN))
you need to figure out where the injury is coming from
what is the NSAID effect on kidneys?
NSAID can constrict afferent arteriole of glomerulus -->decrease hydrostatic pressure in glomerulus
what is the most common cause of Acute kidney injury in ambulatory patient is what? other indications? ************
-renal artery stenosis
-meds:diuretic, NSAIDs, ACEI,ARB
patient that comes in dehydrated with kidney injury, what should you immediately ask about and immediately stop?
what happens when you are taking NSAID + ARB/ACEI with renal injury?***********
Decreased hydrostatic pressure I. Glomerulus--->Decrease in GFR.
what is the common treatment for post-renal AKI? *******
foley catheter--relief obstruction
-when someone pees a lot immediately, make sure they dont get volume depleted.
****only replace 1/2 the liquid they peed out/output
what is the most common cause of AKI in hospitalized patient?********
acute tubular necrosis
RBC cast and dysmorphic RBC indicates what******
which patients is most likely in need of kidney biopsy
what are the two major causes of ATN?******
ischemia: not delivering blood correctly (low perfusion to kidneys)
toxins: some sort of medication (antibiotics: Aminoglycosides)
Features of ATN****
Muddy brown casts***
history of precipitating event
which disease have WBC casts?****** what is the most common cause for this?
Acute interstitial nephritis (AIN)--usually due to rxn to medication (Naficillin)
what are some diagnostic clues for AIN
-eosinophils on urine microscopy
-exposure to new medication