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High white blood cell count

Medically reviewed by Drugs.com. Last updated on Dec 15, 2022.

Definition

A high white blood cell count is an increase in cells in the blood that fight infections.

What's considered high in a white blood cell count varies from one lab to another. This is because laboratories set their own reference ranges based on the populations they serve. In general, for adults a count of more than 11,000 white blood cells in a microliter of blood is considered high.

Causes

A high white blood cell count usually means one of the following has increased the making of white blood cells:

Specific causes of a high white blood cell count include:

When to see a doctor

A test a health care provider orders to diagnose a condition can reveal a high white blood cell count. A high white blood cell count is rarely found by chance.

Talk to your care provider about what your results mean. A high white blood cell count plus results from other tests might show the cause of your illness. Or you might need other tests for more information about your condition.

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