Definition
By Mayo Clinic staffHigh white blood cell count is an increase in disease-fighting cells (leukocytes) circulating in your blood. High white blood cell count is also called leukocytosis.
The threshold for high white blood cell count varies from one medical practice to another. A count of more than 10,500 leukocytes in a microliter of blood is generally considered a high white blood cell count. The threshold for leukocytosis in children varies with age and sex.
- Laboratory reference values. Leukocytes. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2010.
- Coates TD. Definition and mechanisms of leukocytosis and neutrophilia. http://www.uptodate.com/home/index.html. Accessed July 12, 2010.
- Blood studies: Hematology and coagulation. In: Fischbach FT, et al. A Manual of Laboratory and Diagnostic Tests. 8th ed. Philadelphia, Pa.: Lippincott Williams & Wilkins; 2009. http://ovidsp.ovid.com/ovidweb.cgi?T=JS&NEWS=N&PAGE=booktext&D=books&AN=00140036/7th_Edition/11&XPATH=/OVIDBOOK%5B1%5D/METADATA%5B1%5D/TBY%5B1%5D/EDITORS%5B1%5D. Accessed July 12, 2010.

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