Swollen Lymph Nodes: Facts, Common infections & Treatments

What's in this article?

1 Swollen lymph nodes facts
2 What are lymph nodes?
3 What causes swollen lymph nodes?
4 Swollen Lymph Nodes Symptoms
5 How are swollen lymph nodes treated?
6 How long will lymph nodes remain swollen?

Swollen lymph nodes facts

Lymph nodes, also referred to as lymph glands, are important part of the immune system.
Lymph nodes are located throughout the body, but visible and palpable only when they are enlarged or swollen.
Lymph nodes are regional, and each group of them corresponds to a particular region of the body and reflects abnormalities in that region. Common areas where swollen lymph nodes are more prominent and therefore more readily noticeable are behind the ear, in the neck, the groin, under the chin and in the armpits.
These are also usually the areas your doctor will check for lymph node enlargement.
In general, infections are the most common causes of lymph node enlargement. Other causes include inflammation and cancers. There is a wide variety of infections from a strep throat or ear infection, to mononucleosis or HIV infection, which can cause swelling of lymph nodes.
Lymphoma and leukemia cause swelling of lymph nodes, and many cancers spread to lymph nodes.
Rarely, a medication can cause swelling of a lymph node.
Symptoms associated with lymph node swelling and related diseases can include pain in the area of the swelling, fever and fatigue.
Not all swollen lymph nodes are abnormal.

What are lymph nodes?

Lymph nodes are small, bean-shaped glands throughout the body. They are part of the lymph system, which carries fluid (lymph fluid),nutrients, and waste material between the body tissues and the bloodstream.

The lymph system is an important part of the immune system, the body’s defense system against disease. The lymph nodes filter lymph fluid as it flows through them, trapping bacteria, viruses, and other foreign substances, which are then destroyed by special white blood cells called lymphocytes.

Lymph nodes may be found singly or in groups. And they may be as small as the head of a pin or as large as an olive. Groups of lymph nodes can be felt in the neck, groin, and underarms. Lymph nodes generally are not tender or painful. Most lymph nodes in the body cannot be felt.

What causes swollen lymph nodes?

Lymph nodes often swell in one location when a problem such as an injury, infection, or tumor develops in or near the lymph node. Which lymph nodes are swollen can help identify the problem.

The glands on either side of the neck, under the jaw, or behind the ears commonly swell when you have a cold or sore throat. Glands can also swell following an injury, such as a cut or bite, near the gland or when a tumor or infection occurs in the mouth, head, or neck.
Glands in the armpit (axillary lymph nodes) may swell from an injury or infection to the arm or hand. A rare cause of axillary swelling may be breast cancer or lymphoma.
The lymph nodes in the groin (femoral or inguinal lymph nodes) may swell from an injury or infection in the foot, leg, groin, or genitals. In rare cases, testicular cancer, lymphoma, or melanoma may cause a lump in this area.
Glands above the collarbone (supraclavicular lymph nodes) may swell from an infection or tumor in the areas of the lungs, breasts, neck, or abdomen.

Common sites for swollen lymph nodes include the neck, groin, and underarms.

The most common cause of swollen lymph nodes is an infection, particularly a viral infection, such as the common cold. However, there are other types of infections, including parasitic and bacterial, and other possible causes of swollen lymph nodes. They include:

Common infections

Strep throat
Measles
Ear infections
Infected (abscessed) tooth
Mononucleosis
Skin or wound infections, such as cellulitis or erysipelas
Human immunodeficiency virus (HIV) the virus that causes AIDS

Uncommon infections

Tuberculosis
Certain sexually transmitted infections, such as syphilis
Toxoplasmosis a parasitic infection resulting from contact with the feces of an infected cat or eating undercooked meat
Cat scratch fever a bacterial infection from a cat scratch or bite

Immune system disorders

Lupus a chronic inflammatory disease that can target your joints, skin, kidneys, blood cells, heart and lungs
Rheumatoid arthritis a chronic inflammatory disease that targets the tissue that lines your joints (synovium)

Cancers

Lymphoma cancer that originates in your lymphatic system
Leukemia cancer of your body’s blood-forming tissue, including your bone marrow and lymphatic system
Other cancers that have spread (metastasized ) to lymph nodes

Other possible, but rare causes include certain medications, such as the anti-seizure medication phenytoin (Dilantin), and preventive medications for malaria.

Swollen Lymph Nodes Symptoms

The symptoms of swollen lymph nodes depend upon both the location and cause of the enlargement.
Patients may experience symptoms of an upper respiratory infection (runny nose, sore throat, fever) and feel slightly tender or painful nodes under the skin around the ears, under the chin, or on the upper part of the neck under the jaw.
Sometimes there may be a skin infection or redness and streaking of the skin, and one may feel an enlarged node in the vicinity in the direction toward the heart.
Swelling of a lymph node located deep inside the body may have different consequences from swelling of those just under the skin. The blockage in the flow of lymph from swelling in a deeper node may cause a swelling of a limb or, for example, swelling of lymph nodes in the lung could cause a chronic cough, even though you would not be able to feel a swollen node in that location.
Generalized swelling of lymph nodes throughout the body may occur due to infection, systemic inflammation, or cancer.

How are swollen lymph nodes treated?

Treatment for swollen glands focuses on treating the cause. For example, a bacterial infection may be treated with antibiotics, while a viral infection often goes away on its own. If cancer is suspected, a biopsy may be done to confirm the diagnosis.

Any swollen lymph nodes that don’t go away or return to normal size within about a month should be checked by your doctor.

How long will lymph nodes remain swollen?

Lymph nodes may remain swollen or firm long after an initial infection is gone. This is especially true in children, whose glands may decrease in size while remaining firm and visible for many weeks.