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Leukocytosis, a disease affecting the body's white blood cells

The body’s white blood cells (leukocytes) help to protect against illness and disease and fight off other harmful germs. When these white blood cells are above the normal range, it is called leukocytosis. Common causes of leukocytosis include having an infection, but it also can occur if a person has had bone tumors or leukemia.

Other stresses to the body caused by strenuous exercise, epileptic convulsions, emotional stress, and pregnancy/labor are also known to be causes of this condition. Leukocytosis can also be caused by anesthesia, as a side effect of medication or an epinephrine injection.

Blood tests are used to diagnose this disease. Bone marrow biopsies may also be used.

There are different types of white blood cells and types of leukocytosis which are classified by the type of white blood cell that is increased.

Neutrophils are the most common type of white blood cell. They are the body’s first line of defense in fighting infection and viruses, and often signal other components of the immune system to respond to these foreign invaders.

Neutrophilia is a type of leukocytosis that affects neutrophils and is often associated with infections and inflammation from injuries and arthritis. Known causes of neutrophilia include:

  • An adverse reaction to drugs such as steroids, lithium and inhalers

  • Emotional or physical stress

  • Certain types of leukemia

  • Removal of Spleen

  • Smoking

Lymphocytes in your blood create T cells that directly destroy harmful invaders and B cells that produce antibodies to recognize these foreign cells if seen again by the immune system.

Lymphocytosis is an increased number of these types of cells. It is a common type of leukocytosis and is associated with both viral infections and leukemia. Known causes of lymphocytosis include:

  • Allergic reactions

  • Viral infections

  • Whooping cough (pertussis)

  • Certain types of leukemia

Monocytes. These types of cells are larger and live longer than many white blood cells. They work to help to break down bacteria and remove cellular debris.

Monocytosis, which is uncommon, happens when there are a high number of these cells. Known causes of monocytosis include:

  • Infections caused by certain things including mononucleosis, Epstein Barr virus, tuberculosis and fungus

  • Removal of Spleen

  • Autoimmune diseases

Eosinophils are white blood cells that attack parasites and react to inflammation.

An elevated number of these cells is Eosinophilia. Known causes of eosinophilia include:

  • Seasonal allergies

  • Other types of allergic reactions

  • Certain kinds of skin diseases

  • Certain types of cancer

Basophils are small cells that create a reaction when infectious agents invade your blood. These type of white blood cells secrete chemicals such as histamine, a marker of allergic disease, which help to control the body's immune response.

Basophilia, which is a rare condition is when there is a high level of these types of cells. It is associated with leukemia. Known causes of basophilia include:

  • Bone marrow cancer or leukemia (more common)

  • Allergic reactions (less common)

Signs and Symptoms

  • Allergic reaction in the lungs that causes wheezing or breathing problems

  • Allergic skin reaction including hives, itchy skin and rashes

  • Dizziness, or feeling faint or sweaty

  • Infection site pain or fever

  • Mouth, stomach or intestinal bleeding (areas of body covered with mucosa)

  • Pain or tingling in your legs, arms or abdomen

  • Stroke

  • Vision problems

  • Weight loss