• Lymphocytosis is the hallmark of a viral infection.
• No, we don't use the term right-shifted differential.
• Many of the lymphocytes will demonstrate reactive features, which we unfortunately referred to as "atypical changes."
• We now reserve the term "atypical" for disturbances in maturation, even suggesting (dysplasia). Unfortunately, this misapplied term will be with us for a long time.
• As with the rise in PMNs with a bacterial infection, the lymphocytosis of a viral infection can be striking. Values of up to 20,000 are possible.
• Mononucleosis is the quintessential example. The irony is that the cells for which this disease is named are actually lymphocytes and not monocytes at all.

What about the scatter plot?                                                          Back