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Leukocytosis (High White Blood Cell Count)


WBCs are a kind of blood cell that helps the body fight illness. The bone marrow produces all blood cells, including the WBCs.

A sufficient number of WBCs is required for the circulatory system to function properly. Since The primary function of WBCs is to combat disease, they are critical to one’s overall health and well-being. The bone marrow produces a steady supply of these cells. When they are not needed to aid the body’s fight against an infection or illness, they are stored in the blood and lymphatic systems until they are required.

An increased white blood cell count, or leukocytosis, is an indication of inflammation, infections, physical damage, and immune system malfunction. A high WBC count suggests that the number of disease-fighting cells in the blood has increased.

What is considered a high WBC count?

The presence of more than 11,000 WBCs (leukocytes) per microliter of blood corresponds to a high white blood cell count.

To establish if a patient has leukocytosis, doctors often conduct a CBC test i.e. complete blood count. It may be requested by the primary care physician as part of a routine physical examination or to assist in the identification of a specific illness.

Although an increased WBC count does not always imply sickness, it may suggest the existence of an underlying problem such as infection or stress. It may also be the result of a stressful event, allergies, or a medical issue. As a consequence, a high white blood cell count usually requires additional investigation and testing.

Depending on the underlying reason, WBC issues may show in a number of ways, although some people may be asymptomatic (without symptoms). Some of the symptoms associated with high WBC count are fatigue, fever, dizziness, body pain, sweating, chills, mouth sores, cough and bruising. 

A high WBC count may resolve on its own at times. For instance,occurrence of fever as a consequence of a sickness. When your body is attacked, it produces an increased amount of WBCs to combat the bacterium or virus that is causing the problem.

In certain cases, further treatment to decrease the WBC count may be required. It is important to understand both the cause and possible symptoms of a high WBC in order to manage it properly.


A rise in WBC count may be caused by infections, abnormal bone marrow, immunological disorders, chronic lung sickness, inflammatory or allergic reactions, smoking, and physical as well as emotional stress.

  • Infection: When microorganisms multiply in the tissues or blood, the bone marrow becomes more active. It generates an increased amount of WBCs to fight the infection. Since infection may induce inflammation and WBCs are produced in response to inflammation, an increase in WBC count can be ascribed to both the inflammatory response and the infection. The body’s response to an infection is the most common cause of an elevated WBC count. 
  • Leukemia: An increased WBC count may be caused by leukemia. This is a cancerous alteration in the blood and bone marrow that causes an abnormally high production of WBCs, which is harmful to the patient’s health. Individuals suffering with leukemia are more vulnerable to other illnesses since these additional cells are often unable to function correctly. 
  • Autoimmune disorders: Certain autoimmune illnesses like Crohn’s and Graves’ disease, may result in an increase in WBC counts. 
  • Smoking and COPD: They may both cause a reduction in airflow to the lungs, which can be fatal. As the lungs and airways become more inflamed, the body reacts by generating more WBCs. Thus these factors are also responsible for high WBCs.

Some other conditions responsible for elevated levels of WBCs are:


leukocytosis is a response to an underlying illness, its symptoms are frequently ambiguous. Common leukocytosis symptoms include fever, weariness, weakness, and a general unwell sensation. Leukocytosis is frequently detected by normal blood tests for other medical reasons, and individuals may not exhibit obvious symptoms directly connected to the disorder. The finding of leukocytosis often necessitates additional inquiry to establish the cause.


A blood test to determine the total white blood cell count is used for leukocytosis diagnosis. White blood cell normal ranges can vary slightly based on the laboratory and the individual’s age and gender. A white blood cell count of more than 11,000 to 11,500 cells per microliter of blood is considered high and indicates leukocytosis. Additional tests, such as a differential white blood cell count, bone marrow aspiration, and other diagnostic procedures, may be required to discover the underlying cause of leukocytosis.


Leukocytosis treatment relies mainly on resolving the underlying illness or trigger that has resulted in an elevated white blood cell count. Leukocytosis is not an illness in and of itself but rather a symptom of a more significant issue, ranging from infections (bacterial, viral, or fungal), inflammatory disorders, and autoimmune diseases to more severe problems like leukemia. As a result, treatment will differ significantly depending on the precise cause.

When an infection is the root cause, antibiotics or antiviral drugs may be recommended to treat the illness and, as a result, lower the white blood cell count. Medications such as corticosteroids or immune-modulating therapies may be prescribed to regulate the immune response and reduce inflammation in inflammatory or autoimmune disorders. A hematologist-oncologist will devise a treatment plan for more severe illnesses like leukemia, including chemotherapy, radiation therapy, or stem cell transplantation.

When To See A Doctor

You should seek medical attention if you have signs of inflammation, infection, or an autoimmune disease. You should see your doctor if you have been experiencing the following sign or symptoms:

A high WBC count is often found when the doctor requests a test to identify the existence of a disease in the body.

A high WBC count, when coupled with the results of other tests, assists in the identification of the cause of the illness. Alternatively, the doctor may advise further tests to get a better understanding of the issue and underlying cause.


This information is intended for educational purposes only and should not be considered a substitute for professional medical advice. If you have concerns about Leukocytosis or any other medical condition, please see a doctor for an accurate diagnosis and personalized treatment suggestions.