Why get tested? If your doctor thinks that you might have an infection or a disease that affects the production of white blood cells and to monitor treatment
When to get tested? As part of a complete blood count (CBC), which may be ordered for a variety of reasons
Sample required? A blood sample drawn from a vein in your arm or by a fingerstick (children and adults) or heelstick (newborns)
This article was last reviewed on March 2, 2008.
This page was last modified on April 8, 2009.
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