White Blood Cell Count Test
This blood test provides insight into your immune system by measuring the number of white blood cells in your blood.
What is a White Blood Cell Count Test?
A White Blood Cell (WBC) Count Test is a key part of a full blood count and helps assess your body’s ability to fight infection, respond to inflammation or manage immune-related conditions. White blood cells play a vital role in your immune defence. Abnormal levels can point to underlying issues such as infection, autoimmune disorders, bone marrow problems or the effects of certain medications.
Why is a White Blood Cell Count Test carried out?
A WBC count is used to detect infections, inflammation or immune system issues. It is also useful in monitoring conditions such as leukaemia or the effects of chemotherapy and immunosuppressive treatments.
What is a normal WBC count range?
In adults, a normal white blood cell count typically ranges from 4,000 to 11,000 cells per microlitre of blood. However, ‘normal’ can vary slightly depending on the laboratory, and results should always be interpreted in the context of your overall health and symptoms.
What does a high white blood cell count mean (leukocytosis)?
Leukocytosis means your white blood cell count is higher than normal. This is often a response to infection, inflammation, physical stress or trauma. In some cases, it may be associated with bone marrow conditions or certain types of cancer. A persistently high count may require further investigation, especially if accompanied by other symptoms.
What does a low white blood cell count mean (leukopenia)?
Leukopenia refers to a reduced number of white blood cells, which may impair your ability to fight infections. It can result from viral illnesses, autoimmune diseases, bone marrow disorders or side effects of medications such as chemotherapy. If levels fall significantly, it may increase your risk of infections and warrant further blood tests and assessments.
Can the WBC count fluctuate daily?
Yes. White blood cell levels can vary slightly from day to day due to factors like stress, time of day, recent infections or medications. Minor fluctuations are usually harmless, but notable or persistent changes may indicate an underlying issue.
White Blood Cell Count Test FAQs
- What does a white blood cell count test show?
It measures the total number of white blood cells in your blood, helping identify infections, immune responses or bone marrow disorders.
- Is the WBC test part of a routine full blood count?
Yes. A white blood cell count is included in a full blood count, which also measures red blood cells, platelets and other markers.
- Can medications affect white blood cell levels?
Yes. Certain medications (including chemotherapy, antibiotics or steroids) can lower or raise your white cell count.
- Do I need to fast before a white blood cell count test?
No, fasting is not necessary before a white blood cell count test. You can attend your appointment as normal.
Why Choose The Forbury Clinic?
At The Forbury Clinic, we understand that changes in immune health can feel uncertain. That’s why our consultant-led team provides prompt, accurate white blood cell testing with expert follow-up support when needed. Whether you’re investigating new symptoms or monitoring a known condition, we deliver results with clinical precision and clear, compassionate care – ensuring you’re supported at every step.
Book a full blood count today to check your white blood cell levels and better understand your immune health.