Test guide
White Blood Count (WBC)
A white blood count measures the number of white blood cells (WBCs) in your blood. White blood cells, also called leukocytes, are part of your immune system . They are a type of blood cell made in your bone marrow and found in your blood and lymph tissue (part of your immune system). If you are injured or get sick, the white blood cells will travel through your bloodstream and tissues to where they are needed. There, they will help your body fight off infections and other diseases.
What it is for
A white blood count is most often used to help diagnose or monitor disorders related to having a high white blood cell count or low white blood cell count. Disorders related to having a high white blood count include: Source: MedlinePlus, National Library of Medicine. Medical test information is public domain. Source identity and definition checked automatically on 2026-10-18. No individual clinical interpretation or human reviewer is asserted.
Limitations
Reference intervals and interpretation depend on the laboratory, specimen, method and clinical context. This source definition is educational information; it does not establish a diagnosis, product approval or suitability for an individual.
Also known as
- WBC count, white cell count, white blood cell count, Leukocyte Count, WBC
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