A WBC count is part of the full blood count (FBC), which is requested for a variety of reasons. Changes in the WBC, whether it is high or low, may indicate a worsening or improvement in a medical condition.
An elevated number of white blood cells is called leucocytosis. This can result from bacterial infections, inflammation, leukaemia, trauma, medication, or stress. A WBC count of 11.0–17.0x109/L cells would be considered mild to moderate leucocytosis.
A decreased WBC count is called leucopenia. It can result from many different situations, such as
medication, especially chemotherapy, or radiotherapy
Increased WBC levels may be seen during the late stages of pregnancy.
If you have had your spleen removed, you may have a persistent mild to moderate increased WBC count.
The WBC count tends to be lower in the morning and higher in the late afternoon. WBC counts change with age with normal newborns and infants typically have a higher WBC counts than adults. It is not uncommon for the elderly to fail to develop leucocytosis (a high WBC) as a response to infection.
There are many drugs that cause both increased and decreased WBC counts.
This article was last reviewed on 18 November 2010. | This article was last modified on 18 June 2015.
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