The medical term for a high white blood cell count is leukocytosis. White blood cells are your body's protection when you have an infection and their purpose is to attack any virus, bacteria or fungus that is present. If your white blood cell count is abnormally high, it can be the indication of some type of illness. Increased neutrophils, a type of white blood cell, is called neutrophilia. Neutrophila is the most frequent type of leukocytosis.
If your white blood cell count is exceptionally high, it may mean the presence of an infection. Your body's immune system responds to infection by sending white blood cells, which are stored in your tissues, into your circulating blood to kill fungi or bacteria, and then your bone marrow begins producing more white cells. After the infection has cleared up, your white blood cell count should return to a normal level.
Certain medications can increase your body's production of neutrophils, causing an elevated white blood cell count. Some of these medications include corticosteroids, antibiotics, anti-seizure drugs and epinephrine.
Bone Marrow Disease
Because white blood cells are produced in your bone marrow, some diseases, such as myeloproliferative disorders of the bone marrow, can cause an increased production. Some of these include the various types of leukaemia, myelofibrosis, polycythemia vera and some cancers.
Removal of your spleen can result in a slightly higher level of white blood cells. During the last month of pregnancy and during labour, women may have an elevated white blood count. Other causes of a high level of white blood cells can include smoking, physical or emotional stress and tissue damage. An increased count may also be the result of an autoimmune disorder such as rheumatoid arthritis.
If you have an ongoing condition that warrants a complete blood count test, and an elevated white blood cell count is discovered, you should discuss the results with your doctor. In many cases the cause is simple and easily treatable. However, in some cases additional tests may be needed in order to diagnose your problem.