EM Lab Quiz

QUESTIONS:

  1. What is toxic granulation and what is its significance?
  2. What are Dohle bodies and what are their significance?
  3. What are common causes of normal troponin in acute coronary syndrome?
  4. What are the common causes of false negative D-dimer in pulmonary embolism?
  5. What is a good way to determine if the WBC is elevated from demargination rather than disease?
  6. What non-hepatic disease process can cause massive elevation of the AST >> ALT?
  7. What are 4 transient & benign lab abnormalities that can be caused by severe pain or anxiety?
  8. What factors can cause a falsely low BNP
  9. Does renal failure cause an elevated troponin-i?
  10. What are some red herring lab abnormalities that can be caused by pulmonary embolism?

 

ANSWERS:

  1. Toxic granulation is a marker of serious infection (worse than bandemia).  It is also sometimes called toxic vacuoles.
  2. Dohle bodies are a marker of serious infection and are worse than bandemia.
  3. Troponin can be normal in episodic chest pain lasting less than 30 minutes and in the first 2-4 or more hours of an MI
  4. D-dimer can be falsely negative when symptoms have been present for more than a week
  5. Order an ESR &/or a CRP.  Demargination of neutrophils can occur from pain, physiologic stress, anxiety and steroids as well as other causes.  None of these is likely to also cause elevation of the sedimentation rate or C reactive protein
  6. Rhabdomyolysis causes elevation of CK >> AST >> ALT
  7. The “stress quadrad” is high WBC, high glucose, low potassium (from shift) and low bicarb (from hyperventilation)
  8. Obesity can lower the BNP
  9. It should not.  It can cause an elevated troponin-t however.  Elevated troponin-i should not be blamed on renal failure.  If you pay attention you will notice that most dialysis patients have a normal troponin-i
  10. PE can cause elevations of BNP, troponin and the WBC count that can lead to erroneous diagnosis of cardiac or infectious diseases