How Do I Calculate Total Lymphocyte Count?

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Calculate a total lymphocyte count by multiplying the white blood cell count by the percentage of lymphocytes in a complete blood cell count test, according to Aetna InteliHealth. Typical lymphocyte counts in the blood range from 15 to 40 percent of all white blood cells.

Lymphocyte levels vary depending on several factors, notes Aetna InteliHealth. Viral infections and drugs may alter lymphocyte counts. Totally healthy people may also appear to have low lymphocyte levels. For example, one lab may report a total white blood cell count of 6,000, which is considered a normal number. The percentage of lymphocytes may also be normal at 16 percent, yet the total lymphocyte count is 960. The lab test may say the 960 count is low even when other figures sit within normal ranges.

Some websites provide online calculators for lymphocyte counts, such as the Health Sciences Library System at the University of Pittsburgh. Input the total white blood cell count as a number, index, points or score. Include the lymphocyte count as percentage, fraction or ratio. A separate blank on the right side of the screen shows the absolute number of lymphocytes up to three decimal places.

A white blood cell count includes T cells and B cells, according to MediaLab Incorporated. Someone’s T cells get further divided into helper cells and cytotoxic suppressor cells. A white blood cell count has absolute numbers for each cell and ratios of helper cells to suppressor cells.