Leukocyte count (WBC)

Leukocyte count (WBC)

April 28, 2022

Leukocyte count (WBC)

What is a Leukocyte count (WBC)?

A white blood cell (WBC) count is a test that measures the number of white blood cells in your body. It may also be called a leukocyte test. This test is often included with a complete blood count (CBC), which is commonly used to screen for different conditions that may affect your overall health.

The term “white blood cell count” is also used more generally to refer to the number of white blood cells in your body.

There are several types of white blood cells, and your blood usually contains a percentage of each type. Sometimes, however, your white blood cell count can fall or rise out of the healthy range. This may be due to an underlying condition or infection.

Why is this analysis important?

A WBC count is often done as part of a full blood count. These tests may be ordered as part of a routine blood test.

White blood cells, also called leukocytes, are an important part of the immune system. They originate in the bone marrow but move throughout the bloodstream. These cells help fight infection by attacking bacteria, viruses, and germs that invade the body.

A white blood cell count can detect hidden infections within your body and alert doctors to undiagnosed medical conditions, such as autoimmune diseases, immune deficiencies, and blood disorders. This test also helps doctors monitor the effectiveness of chemotherapy, radiation treatment, and other therapies in people with cancer.

What are some of the causes of high Leukocyte count (WBC) levels?

Leukocytosis is the medical term used to describe a high WBC count. This can be triggered by:

  • Infections such as tuberculosis, sepsis, or septic shock

  • Fever

  • Injury or burn

  • Pregnancy

  • Allergies

  • Asthma

  • A recent vaccination

  • Some medications, such as corticosteroids, epinephrine, and non-steroidal anti-inflammatory (NSAID) drugs

  • Stress

  • Tissue damage

  • Acute hemolysis

  • Hemorrhage

  • Leukemoid reaction

  • Heart attack

  • Surgery

What are some of the causes of low Leukocyte count (WBC) levels?

Leukopenia is the medical term used to describe a low WBC count. This can be triggered by:

  • Autoimmune disorders

  • Bone marrow disorders or damage

  • Severe infections

  • Liver and spleen diseases, such as an enlarged spleen

  • Lupus

  • Radiation therapy

  • Some medications, such as chemotherapy and antibiotics

  • Lymphoma

  • Alcoholism

  • Some infectious diseases

Other considerations

Most times this test is complemented with a white blood cell count differential, which provides a breakdown of your white blood cell count. It separates the count out by the different types of white blood cells and looks to see if they are in the normal range.

There are five major types of white blood cells. They have different roles in protecting your body from infection and dealing with infected cells. These types of white blood cells include:

  • Neutrophils

  • Lymphocytes

  • Eosinophils

  • Monocytes

  • Basophils