Lymph Nodes

What are lymph nodes?

Lymph nodes are small organs, around the size of a pea, that are responsible for filtering substances that travel through our lymphatic system. They are made up of infection-fighting cells and lymph tissue. Lymph nodes are found in the armpits, neck, groin and many other parts of the body.

If your lymph nodes swell or get bigger, it can be a sign that your body is fighting illness or an infection.

What do lymph nodes do?

Our lymphatic system forms part of our immune system, helping to fight infection. Consisting of vessels, tissues, glands and organs, the lymphatic system moves a colorless liquid, called lymph, back into the blood. As well as protecting us from foreign invaders, the lymphatic system maintains fluid levels in the body, removes waste from cells, and absorbs nutrients and fats.

The lymph nodes are bean-shaped glands that filter and monitor lymph as it passes through them. They recycle the fluid that the body needs and hold onto components that keep us healthy. They destroy and eliminate anything the body doesn’t need, such as invading viruses or infections.

Where are lymph nodes located?

We have hundreds of lymph nodes throughout our body. They are normally found where major blood vessels come together, such as in the neck, armpit, abdomen, chest, behind the ear, and groin.

They are made up of lymph tissue and many types of cells, including white blood cells (lymphocytes), plasma cells, T cells, B cells, dendritic cells, and macrophages.

What medical conditions can affect the lymph nodes?

There are many different conditions that can affect the health of your lymph nodes. These include:

• Swollen lymph nodes: Called lymphadenopathy, this condition causes the lymph nodes to enlarge if the immune system is fighting illness or an infection.
• Lymphoma: This refers to cancers that start in the lymphatic system, including non-Hodgkin’s lymphoma and Hodgkin’s lymphoma.
• Lymphangioleiomyomatosis: This is a lung disease that causes cells to multiply out of control in the lymph nodes, lungs and kidneys.
• Autoimmune lymphoproliferative syndrome: This is a genetic condition in which too many white blood cells collect in the lymph nodes, spleen and liver.
• Mesenteric lymphadenitis: This condition causes swelling of the lymph nodes in the abdomen.
• Kikuchi's disease: This condition causes lymph nodes to enlarge and become painful.
• Castleman disease: Refers to a group of conditions which cause too many cells to grow in the lymphatic system.

What are the symptoms of lymph node conditions?

Symptoms of lymph node conditions will vary, but the most common symptoms are associated with a swelling of the lymph nodes (lymphadenopathy), including:

• Tenderness or pain in the lymph nodes
• Swelling or bulging of the lymph node
• Fever, runny nose or sore throat
• Sweating, usually at night

How are conditions of the lymph nodes diagnosed?

Imaging tests are used to evaluate the size and health of your lymph nodes, including:

• Computed tomography (CT) scan
• Positron emission tomography (PET) scan
• X-ray

A blood test may also be taken to check for signs of illness or cancers that may affect cells within the lymph nodes.

Sometimes, a biopsy of the lymph nodes is performed so a tissue sample can be examined for abnormalities.

How are lymph node conditions treated?

The treatment that is offered will depend on the lymph node condition diagnosed and your symptoms, but may include:

• Antibiotics to fight an infection
• Applying a warm compress
• Chemotherapy, immunotherapy or radiation therapy if caused by certain cancers
• Medication to treat the condition which is causing swelling
• Over-the-counter pain medication
• Removing damaged lymph nodes with surgery

Our lymph nodes are part of the immune system and filter substances to keep us healthy. By taking care of your overall health, and doing things such as taking regular exercise, eating a balanced diet, drinking lots of water and getting enough sleep, your lymph nodes and lymphatic system will work at their best.

Always talk to a doctor if you notice any swelling in your lymph nodes.