Like the blood system, the lymphatic system is essential for the proper functioning of the body. It is made up of specific organs and a large network of lymphatic vessels, in which the lymph circulates. This liquid ensures in particular the circulation of lymphocytes known for their role in the immune system.

Lymphatic network

The lymphatic system is made up of a large network of lymphatic vessels. These are arranged in parallel with certain blood vessels. They are found in many tissues of the body except the nervous system, bone marrow, cartilage and muscles. Each vessel connects tissue to a lymphatic organ.

Lymphatic organs

The lymphatic system has several specific organs. Among them, we distinguish:

• primary lymphatic organs, including bone marrow and thymus, which are responsible for the production of lymphocytes;
• secondary lymphatic organs, including lymph nodes and spleen, which differentiate and proliferate lymphocytes.

lymph

Lymph circulates within the lymphatic system. This whitish-colored biological fluid has a composition similar to blood plasma, with the exception of red blood cells. Lymph contains white blood cells, nutrients and wastes. The lymphatic system contains between 1 and 2 liters of lymph.

Structure of the lymphatic system

Although the structure of the lymphatic system has similarities with that of the blood system, there are some differences. The most important is theno pump in the lymphatic system. If the blood is propelled by the pumping activity of the heart, the lymph circulates through the structure of the walls of the lymphatic vessels, muscle contractions and body movements.

Immune response

The lymphatic system plays an essential role in the immune system to ensure the body’s defense. The lymphatic organs ensure the production of lymphocytes while the lymph ensures their transport in the lymphatic network. These white blood cells are involved in destruction of pathogens.

Drainage of the body

Within the lymphatic system, lymph can drain certain fluids when they are present in excess in the tissues. This drainage contributes to the detoxification of the body.

Functioning of the body

In addition to ensuring the transport of white blood cells, lymph contributes to the circulation of nutrients and hormones essential to the body.

Lymphoma

Cancer cells can grow in the lymphatic system. Depending on the appearance of cancer cells, there are two forms of lymphoma:

• Hodgkin lymphoma : Also called Hodgkin’s disease, this cancer of the lymphatic system is characterized by abnormal development of type B lymphocytes. Their proliferation and accumulation in the lymph nodes leads to the development of a malignant tumor. This form is, however, rarer than so-called non-Hodgkin’s lymphomas.
• Non-Hodgkin lymphoma : Formerly called lymphosarcoma, this cancer can take many forms, such as Burkitt’s lymphoma. Non-Hodgkin lymphomas are characterized by an abnormal and uncontrolled multiplication of lymphocytes.

Lymphoedème

It results in swelling of a limb, especially in the legs (leg edema). It is due to a accumulation of lymph in the interstitial tissues, which occurs when the lymphatic network no longer drains the lymph sufficiently. Lymphedema can be genetic in origin but can also appear following infection, cancer or surgery.

Treatment of lymphomas

It depends on the type of lymphoma diagnosed (Hodgkin’s disease or non-Hodgkin’s lymphoma), its course and its severity. Cancer treatment can be done with chemotherapy, radiotherapy or immunotherapy. In more severe cases, a bone marrow transplant may be necessary.

Treatment of lymphedema

This treatment is symptomatic, that is to say, it aims to relieve the symptoms of lymphedema. Compression bandages, elastic restraint, manual lymphatic drainage and physiotherapy sessions may in particular be recommended.

Lymph node examination

This clinical examination is very frequently used. It involves palpating the lymph nodes to assess their size and consistency. Swollen glands are often a sign of infection.

Lymphocyte analysis

Circulating through the lymphatic system, these white blood cells can be analyzed. The levels of white blood cells are notably evaluated during a blood test. Using microscopy, the size and shape of lymphocytes can also be studied to check for abnormalities.

Lymphoscintigraphie

This medical imaging test allows you to visualize the lymph vessels and nodes. Lymphoscintigraphy can be performed in the upper limbs as well as the lower limbs. This lymphography makes it possible to deepen a diagnosis or to confirm the lymphatic origin of a disease.

Surgical biopsy

A tissue or lymph node sample may be taken if lymphoma is suspected.

For a long time, lymph was considered “white blood” because of its whitish color.