Clinical QuickieHematology/Coagulation
WBC
Leukocytosis does not equal infection.
The Total Count Is Only the Start
WBC can rise from infection, inflammation, physiologic stress, medications, smoking, tissue injury, asplenia and hematologic disease.
The total count alone does not identify the cause.
Look at Trajectory and Differential
Compare with baseline and duration.
Absolute cell counts, differential and smear are more informative than the total WBC alone.
Medication and Stress Effects Are Common
Corticosteroids, beta agonists, lithium, epinephrine and growth factors can elevate WBC.
Surgery, trauma, seizures and other stressors can cause demargination.
Treat the Syndrome, Not the Count
Fever, focal symptoms, exam, hemodynamics, cultures/imaging when indicated and other cell lines determine whether infection or marrow disease is plausible.
The WBC is one data point in a clinical picture.
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