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The CBC: Toxic granulation, Dohle bodies, etc.

  • Automated Diff: done by Coulter counter by a spectrometer.  Can pick up bands, blasts and abnormal RBC morphology
  • Manual Diff: Only done if ordered or there are red flags on the automated diff, which may vary by hospital.  Shows WBC morphology

WBC morphologytoxic granulationDohle bodies or vacuoles are red flags for serious infection, more so than bands.  Always look to see if they have been called out.  Atypical lymphocytes have causes beyond mononucleosis.  For these search the sample page below.

RBC morphologyHowell-Jolly bodies can signify hyposplenism, leukemia, thalassemia, or pernicious anemia and the first two of these are associated with decreased immunity.  Pappenheimer bodies can signify splenectomy, MDS, sickle cell disease, sideroblastic anemia, hemolysis or lead poisoning, the first three of which can be associated with decreased immunity

WBC Demargination: my strategy for how to handle an elevated WBC count that I think is just due to demargination is as follows:  These WBC counts will usually be between 11-16, although they can be higher.  I order a Sed rate and a CRP.  If  both are normal, I usually don’t worry about the elevated WBC count if my clinical suspicion is also low.


Pain, anxiety, trauma, pregnancy or any form of emotional or physiologic stress can cause any or all of the following lab abnormalities, probably from endogenous adrenaline release and/or hyperventilation

  1. Leukocytosis from demargination (often left shift but should not have toxic granulation or Dohle bodies and CRP should be normal)
  2. Hyperglycemia from adrenalin
  3. Hypokalemia from shift into cells similar to giving albuterol for hyperkalemia
  4. Low bicarb non-gap metabolic acidosis to compensate for respiratory alkalosis (hyperventilation).  This probably starts within minutes but is only remarkable if hyperventilation has been going on for more than half an hour (my estimate)