Lymph nodes are small glands that filter lymph, the clear fluid that circulate through the lymphatic system. They become swollen in response to infection and tumors.
Lymph circulates through your entire body through channels similar to blood vessels (lymphatic system). The lymph nodes are glands that store white blood cells, which are responsible for killing invading organisms.
The lymph nodes act like a military checkpoint. When bacteria, viruses and abnormal or diseased cells pass through the lymph channels they are stopped at the node.
When faced with infection or illness, the lymph nodes accumulate the debris of the disease such as bacteria, and dead or diseased cells.
Lymph nodes (glands) are located throughout the body and near the skin surface on either side of the neck, in the armpits, under the jaw, on either side of the groin, and above the collarbone. They become swollen in relation to infection in that area. For example, the lymph nodes in the neck can become swollen in response to an upper respiratory infection, like the common cold.
Lymph nodes become swollen in response to illness or infection. It is one sign that your lymphatic system is working to rid your body of the agents responsible.
Swollen lymph glands in the head and neck are normally caused by illnesses such as (Mayo):
- ear infections
- HIV infection
- infected tooth
- mononucleosis (mono)
- skin infections
- strep throat
More serious conditions such as immune system disorders or cancers can cause the lymph nodes throughout the body to swell. Immune system disorders that cause the lymph nodes to swell include lupus and rheumatoid arthritis.
Any cancers that spread in the body can cause the lymph nodes to swell. When cancer from one area spreads to the lymph nodes, survival rate decreases. Lymphoma, which is a cancer of the lymphatic system, also causes the lymph nodes to swell.
Some medications, and allergic reactions to medications, can cause the lymph nodes to swell. While rare, anti-seizure and antimalarial drugs can cause lymph nodes to swell.
Sexually transmitted infections, such as syphilis, can cause the lymph nodes in the groin area to swell.
A swollen lymph node gland can range from the size of the pea to the size of an egg.
The swollen lymph nodes may be painful to the touch or when making certain movements.
Swollen lymph nodes under the jaw or on either side of the neck may hurt when you turn your head in a certain way or when you are chewing food. They can often be felt simply by running your hand over your neck just below the jawline. They may be tender.
Swollen lymph nodes in the groin may cause pain when walking or bending.
Other symptoms that may be present along with swollen lymph nodes are:
- runny nose
If you experience any of these symptoms, or if you have painful swollen lymph nodes and no other symptoms, consult your doctor. Lymph nodes that are swollen but not tender can be signs of a serious problem, such as cancer.
In some cases, the swollen lymph node will get smaller as other symptoms dissipate. However, if a lymph node is swollen and painful, or if the swelling lasts more than a few days, see your doctor.
If you’ve recently become ill or had an injury, make sure to let your doctor know. This information is vital in helping your doctor determine the cause of your symptoms.
Your doctor will also inquire about your entire medical history. Since certain diseases or medications can cause swollen lymph nodes, your medical history is important in helping to establish a diagnosis.
After discussing the symptoms with your doctor, he or she will perform a physical exam. This consists of checking the size of your lymph nodes and feeling them to see if they’re tender.
After the physical examination, a blood test may be administered to check for certain diseases or hormonal disorders.
If necessary, the doctor may order an imaging test to further evaluate the lymph node or other areas of your body that may have caused the lymph node to swell. Common imaging tests used to check lymph nodes include CT scans, MRIs, X-rays, and ultrasound.
In certain cases, further testing is needed.
The doctor may order a lymph node biopsy. This is a minimally-invasive test, which consists of using thin needle-like tools to remove a sample of cells from the lymph node. The cells are then sent to a laboratory where they are tested for major diseases, such as cancer.
If necessary, the doctor may remove the entire lymph node.
Swollen lymph node glands may become smaller on their own without any treatment. In some cases, the doctor may wish to simply monitor them without treatment.
In the case of infections, you may be prescribed antibiotics or antiviral medications to eliminate the condition causing the swollen lymph nodes. Your doctor might also give you medications such as aspirin and ibuprofen to combat pain and inflammation.
Swollen lymph nodes caused by cancer may not shrink back to normal size until the cancer is treated. Cancer treatment may consist of removing the tumor or any affected lymph nodes. It may also consist of chemotherapy to shrink the tumor.
Your doctor will discuss which treatment option is best for you.