What does a slightly high lymphocyte percentage mean on my bloodwork??

Q. My recent blood test showed a lymphocyte reading of 52%. My total white blood cell count is 5,400. Do I need to worry?

A. I suspect that you are reporting results from a complete blood count (CBC). What a blood test result means for you depends on why your doctor ordered the test.

It's unlikely that you need to worry about your high lymphocyte percentage, assuming there were no other unusual findings reported on your CBC.

The lymphocyte count on a blood sample is measured as a percentage of the total number of white blood cells. In addition to lymphocytes, there are other types of white blood cells, including granulocytes. These are usually the main white cell type in a blood sample. Lymphocytes are next, with a range of 15% to 40%.

Although the blood test report gives the percentage of lymphocytes, the absolute number of lymphocytes per cubic centimeter of blood is more helpful. This count is calculated by taking the total white blood cell count and multiplying it by the percentage of lymphocytes.

A high lymphocyte count is defined as an absolute lymphocyte count of 4,000 or greater. Doctors call this lymphocytosis.

Your absolute lymphocyte count is normal, so you do not have lymphocytosis.

Multiplying your total white blood cell count times 52% equals 2,808 lymphocytes. This is well below the 4,000 number that defines lymphocytosis.

So why might your percent of lymphocytes be a little high? The most common cause is a recent viral infection, such as a cold or the flu. But you could feel perfectly fine and have this test result.

Discuss the result with your doctor to determine if and when the CBC needs to be repeated.

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