Granulocytosis occurs when there are too many granulocytes in the blood. It’s a condition that’s closely related to chronic myelogenous leukemia (CML) and other bone marrow disorders.
Granulocytes are white blood cells that have small granules or particles. These granules contain numerous proteins that are responsible for helping the immune system fight off viruses and bacteria. Neutrophils, eosinophils, and basophils are three types of granulocytes.
Granulocytes form and mature in the bone marrow. Bone marrow is the spongy tissue found inside many of your bones. Bone marrow contains stem cells, which eventually develop into different types of blood cells, including granulocytes. When granulocytes leave the bone marrow, they circulate through the bloodstream and respond to signals from the immune system. Their role is to attack foreign substances that cause inflammation or infection.
An increase in the number of granulocytes occurs in response to infections, autoimmune diseases, and blood cell cancers. An abnormally high white blood cell count usually indicates an infection or disease. Granulocytosis is one condition characterized by a high white blood cell count.
Granulocytosis is the main feature of CML. This is a rare blood cell cancer that begins in the bone marrow. CML is most common among older adults, but it can occur in people of any age. It also affects men more than women. People who have been exposed to radiation, such as radiation therapy for cancer treatment, have a higher risk of developing CML as well.
People with CML may develop the following symptoms:
- abnormal bleeding
- frequent infections
- a loss of appetite
- pale skin
- pain below the ribs on the left side of the body
- excessive sweating during sleep
CML causes a buildup of underdeveloped granulocytes in the bone marrow and bloodstream. Normally, the bone marrow produces immature stem cells in a controlled way. These cells then mature and turn into red blood cells, white blood cells, or platelets. In people with CML, this process doesn’t work correctly. Immature granulocytes and other white blood cells begin to form and multiply uncontrollably, crowding out all the other types of necessary blood cells.
The presence of granulocytes in the bloodstream is normal. These white blood cells are part of your immune system and help defend your body against harmful bacteria and viruses. However, a high number of granulocytes in the blood isn’t normal and usually indicates a health problem.
Bone marrow disorders are a major cause of granulocytosis. Bone marrow is the sponge-like tissue found inside of the bones. It contains the stem cells that produce white blood cells, red blood cells, and platelets. Your white blood cells help fight infection and inflammation, your red blood cells carry oxygen and nutrients, and your platelets enable the blood to clot.
Common bone marrow disorders that can cause granulocytosis are:
- CML, which is a cancer of the white blood cells
- polycythemia vera, which is a disorder in which the body produces too many red blood cells
- primary thrombocythemia, which is a disease in which the body produces too many platelets
- primary myelofibrosis, which is a blood cancer that causes a buildup of scar tissue in the bone marrow
Granulocytosis can also be seen in combination with:
- a bacterial or bloodstream infection
- kidney failure
- some autoimmune diseases, including rheumatoid arthritis
- metastatic cancer
- inflammatory bowel disease
- extreme physical or emotional stress
- a burn injury
- a heart attack
- the use of certain medications, including corticosteroids
This condition is normally diagnosed with a physical examination and a complete blood count (CBC). The CBC is a test that measures the amount of red blood cells, white blood cells, and platelets in your blood. Abnormal numbers of these cells can indicate that you have a disease. If you have granulocytosis, you have too many granulocytes in your blood.
The CBC involves giving a sample of blood. You’ll have blood drawn from a vein in your arm. The blood sample will then be sent to a lab for analysis. As with any blood draw, there’s a small chance of discomfort, bleeding, or infection.
Granulocytosis is a symptom of other conditions. It’s not considered a separate disease, and it usually isn’t treated directly. Instead, treatment addresses the underlying condition causing granulocytosis. Treating any existing conditions should also reduce the number of granulocytes in your blood.
Your treatment will depend on the disease causing your granulocytosis. If it’s related to cancer, your treatment may include the following:
- During a bone marrow transplant, your bone marrow will be removed and replaced with healthy stem cells. These stem cells may come from your body or from a donor’s body.
- Chemotherapy is an aggressive form of chemical drug therapy that helps destroy cancerous cells in the body.
- Radiation therapy uses high-energy radiation to shrink tumors and kill cancerous cells.
- Surgery to remove the spleen may be recommended for people with CML.
Some conditions respond well to medications, and other conditions can be treated with blood transfusions. Your doctor will determine the best treatment plan for you.