Neutropenia is a blood disorder characterized by an abnormally low level in the blood of a type of white blood cell called neutrophils. This damage to the body’s immune system exposes the patient to a risk of infection, the greater the greater the deficit of defense cells. Neutropenia is inherited or acquired, its causes are multiple (autoimmune, chemotherapy, medication, etc.) and its degrees of severity very diverse, from very mild to very serious and involving the life-threatening prognosis. Severe neutropenia often results from anti-cancer treatment.

Symptoms of neutropenia are the multiple opportunistic bacterial and fungal infections that affect the patient. The risk of infection increases with the severity and duration of neutropenia. They preferentially develop on the skin and mucous membranes, the ENT region and the lungs. Staphylococci, streptococci, enterococci, pneumococci and Pseudomonas aeruginosa (++ link ++) are the most frequent agents of infection. The most common signs of neutropenia are: fever, chills, sore throat, mouth ulcers, bleeding gums, dental problems, abdominal pain, diarrhea, lesions around the anus, pain when urinating, cough …

A complete blood count is used to measure the concentration of neutrophils in the blood and to measure the severity of the neutropenia.

• Neutropenia is severe if the number of polynuclear neutrophils (PN) is less than 500 / mm3. It is most commonly the result of treatment for a cancerous tumor, chemotherapy, radiotherapy, or biological agents and poses a serious risk of infection.
• Neutropenia is moderate when the number is between 1700 / mm3 and 1000 / mm3. It is then benign and asymptomatic.

There are three types of white blood cells: monocytes, lymphocytes and granulocytes. The latter are divided between eosinophils, basophils… and neutrophils concerned by neutropenia. They are produced in the bone marrow and the risk of neutropenia occurs when the latter no longer produces enough neutrophils, and / or when they are destroyed prematurely. Neutropenia can have various origins: infectious, medicinal, toxic, post-chemotherapy / radiotherapy, congenital, a disease of the immune system (HIV).

Severe acquired neutropenia is often caused by cancer treatment. Some chemotherapy and radiotherapy treatments can destroy healthy cells in the body, including white blood cells, in addition to cancer cells. Destruction of neutrophils often interferes with the administration of chemotherapy treatment. Note, however, that not all chemotherapies necessarily induce severe neutropenia.

Recently developed drugs are prescribed to stimulate the production of neutrophils by the bone marrow (Neupogen, Neulasta…) and to protect the organism against the occurrence of infections. These are called granulocyte growth factors, or granulocyte growth factors. Antibiotics are given to fight opportunistic infections and the fever that frequently occurs in severe neutropenia. However, taking them too frequently increases the risk that infectious agents develop resistance to antibiotic treatments.