Take a look at some data from POD #1!
Choose the highest yield tests below (more than one choice may be correct)!
Haptoglobin & lactate dehydrogenase (LDH)
Excellent! The haptoglobin is undetectable and the LDH is 1,545 U/L (normal: 140 – 280 U/L).
Peripheral blood smear
In this patient with new anemia, AKI, and the urine findings above, this is a potentially helpful test. Image courtesy of the American Society of Hematology & Peter Maslak
Creatine phosphokinase (CPK)
A good idea, given the large blood without significant hematuria and the appearance of the urine supernatant after centrifuge. CPK for this patient is within the normal range.
Not so fast…Take a closer look at the data we have so far.
Urine hemoglobin & myoglobin levels
Great choice! Hemoglobin is detected in the urine and myoglobin is undetectable.
This patient’s history and urinalysis are not suggestive of a urinary tract infection. Pick again!
Even though this is a cheap, non-invasive test, the utility of this test is very low for this patient. Give it another shot!
Hepatitis B virus, hepatitis C virus, and human immunodeficiency virus (HIV) serologies
These viruses may be associated with various glomerular diseases – these serologies may not be the most helpful tests here. Try again!
With this new data, what’s the diagnosis here? Pick 1!
Contrast-induced nephropathy (CIN)
Acute tubular necrosis (ATN)
Acute interstitial nephritis (AIN)
Confident in your diagnosis? Click here to wrap this case up!