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    Complete Blood Count (CBC)

    Complete Blood Count (CBC)



    Why It Is Done

    A complete blood count may be done to:

    • Find the cause of symptoms such as fatigue, weakness, fever, bruising, or weight loss.
    • Check for anemia.
    • See how much blood has been lost if there is bleeding.
    • Diagnose Reference polycythemia Opens New Window.
    • Check for an infection.
    • Diagnose diseases of the blood, such as leukemia.
    • Check how the body is dealing with some types of drug or radiation treatment.
    • Check how abnormal bleeding is affecting the blood cells and counts.
    • Screen for high and low values before a surgery.
    • See if there are too many or too few of certain types of cells. This may help find other conditions, such as too many eosinophils may mean an allergy or asthma is present.

    A complete blood count may be done as part of a regular physical examination. A blood count can give valuable information about the general state of your health.



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