What is an abnormal white blood cell count?
White blood cells are disease-fighting cells in your blood. Making up only 1% of your blood cells, they fight infection and are essential for good health. There are five different types of white blood cells in your body. Usually, there is an average amount of each type in your blood.
Your white blood cell count is the number of white blood cells in your body (in total and by each type). Your doctor may test your white blood cell count to see if it is normal or abnormal. Your body can have an abnormal white blood cell count from a high number of white blood cells (leukocytosis) or a low number of white blood cells (leukopenia).
There are many different causes for an abnormal white blood cell count ranging from a common cold to a genetic disorder. Successful treatment depends on the cause of your abnormal count.
What are the symptoms of an abnormal white blood cell count?
A high number of white blood cells (leukocytosis) typically does not cause symptoms in and of itself, and any symptoms, such as fever, hives and breathing problems, are typically due to the underlying cause of the abnormal white blood cell count. You may have no symptoms if your high count is related to stress or a reaction to a medication. In rare and extreme cases (typically associated with leukemia), your blood can thicken (hyperviscosity syndrome) causing stroke, bleeding, vision and breathing problems.
A low number of white blood cells (leukopenia) will not produce any symptoms. However, if your count is very low, you may have symptoms of an infection including high fever, chills and sweating.
What causes an abnormal white blood cell count?
While an abnormal white blood cell count can point to a blood disorder or other medical condition, there are a variety of causes for both a high or low count.
A high white blood cell count (leukocytosis) can be triggered by:
- Chronic infection
- Chronic inflammatory diseases
- Malignancy
- Medications such as steroids
- Physical/environmental stresses
- Pregnancy
- Tobacco use
A low white blood cell count (leukopenia) can be triggered by:
- Autoimmune disorders
- Benign ethnic neutropenia
- Familiar neutropenia
- Chronic idiopathic conditions
- Congenital conditions
- Cyclic conditions
- Drug use
- Spleen conditions
- Infections
- Nutrition
- Bone marrow suppression
- Primary bone marrow process
How is an abnormal white blood cell count diagnosed?
Your doctor will perform a physical exam, consider symptoms, current medications, and your and your family’s medical history. Next, your doctor will order one or more blood tests. One of these may be a complete blood count with differential (CBC with diff) which identifies the percentage of each type of white blood cell you currently have in your body. If needed, you may have a bone marrow biopsy (removing a tiny piece of bone marrow for examination).
How is an abnormal white blood cell count treated?
After diagnosing the cause of a high or low white blood cell count and recommending a treatment plan, your doctor will periodically recheck your count.
Treatment of a high white blood count (leukocytosis) is based on the underlying factor or condition causing it. This can include treatment for the underlying condition, medication and lifestyle changes. If your high white blood count becomes extreme and your blood starts to thicken (hyperviscosity syndrome) emergency treatment is needed.
Treatment of a low white blood count (leukopenia) is also based on underlying factors or conditions. Your doctor may stop treatments such as chemotherapy or prescribe a low-bacterial diet. If your white blood cell count is very low, your doctor may refer you to a blood specialist (hematologist).