Too few white blood cells (leukopenia or leukocytopenia)


What is it about ?

Blood consists of three types of cells: red blood cells, white blood cells and platelets. Each type of cell has a specific function. Thus, red blood cells carry oxygen to organs and tissues. Platelets play a role in clotting. White blood cells defend the body against infections. Blood cells are produced in the bone marrow.

There are different types of white blood cells (or leukocytes, from the Greek leukos which means white). The two most important are neutrophils and lymphocytes. A lack of white blood cells is called leukopenia or leukocytopenia. Since this is almost always a lack of neutrophils, it is usually referred to as neutropenia.

A lack of lymphocytes (lymphopenia) is often associated with infections, but it is also seen when the immune system is not working properly.

Neutropenia can be mild, moderate, or severe. It can be acute, appearing over a few hours to a few days, or chronic, developing over a few months to a few years. The causes of neutropenia are numerous:

  • In adults, mild acute neutropenia is usually due to medication, and there are almost never any symptoms. This is a common side effect of anti-cancer drugs (chemotherapy) and drugs that prevent the immune system from working (immunosuppressants).
  • Acute neutropenia is commonly seen withviral infection (eg with the flu), and it usually goes away on its own after recovery, but it can also sometimes last for several weeks. Bacterial infections do not cause a decrease but an increase in the number of neutrophils.
  • In certain immune system conditions (autoimmune diseases), the body considers its own neutrophils to be foreign substances and destroys them.
  • The blood diseases cancerous in nature often cause neutropenia among other abnormalities. In acute leukemia, for example, the blood contains immature white blood cells.
  • Sometimes we don’t find no explanation chronic neutropenia. So the risk of infection is not increased.
  • There are also congenital and hereditary forms neutropenia, but they are rather rare.

Sometimes it is pseudo-neutropenia (false decrease in the number of neutrophils), when a large number of white blood cells stick to the wall of the blood vessels (“margination”). This results in a decrease in the number of white blood cells circulating in the blood, when their total number is normal.

How to recognize it?

Neutropenia can put you at risk for all kinds of infections. You may then have a fever, headache, muscle pain, and generally feel unwell. The other symptoms depend on the location of the infection. The risk of infection increases with the severity of neutropenia and in the presence of conditions with an increased risk of infections, such as decreased immunity. The infection progresses rapidly and, in severe cases, can even lead to severe generalized infection (sepsis), which is life threatening.

How is the diagnosis made?

The diagnosis of neutropenia is made by a blood test. Neutropenia can be discovered by chance, during a routine blood test. Neutropenia is often suspected when there are repeated or unusual infections (for example, upper respiratory tract infections or painful lesions around the mouth or anus).

The doctor will ask you questions, examine you, and review old blood tests to determine when neutropenia started and what could be causing it. He will thus distinguish between acute and chronic forms.

If the doctor suspects a malignant disease, he will refer you to a doctor specializing in blood diseases (hematologist) for a bone marrow sample.

Pseudo-neutropenia is likely if there is an abnormally large increase in the number of neutrophils after taking cortisone.

What can the doctor do?

Treatment depends on the cause. A bacterial infection in a person with severe neutropenia is treated with antibiotics that attack a large number of bacteria (broad spectrum antibiotics).

Growth factors that stimulate the production of white blood cells are sometimes given. Cortisone can help with immune disease. If the spleen increases in size, surgery is done to remove the spleen, if necessary.

If the leukopenia is due to a drug, the doctor will ask you to stop the offending drug immediately, if possible.

A follow-up by blood control may be sufficient in mild to moderate forms.

Want to know more?

Source

Foreign clinical practice guide ‘Leukopenia’ (2000), updated on 23.06.2016 and adapted to the Belgian context on 09.07.2019 – ebpracticenet