Lymph nodes, also referred to as lymph glands, are a crucial part of the immune system. These nodes are located throughout the body but are visible and able to be felt only when they are enlarged or swollen. Lymph nodes are small, soft, round, or oval structures and are connected to each other in a chain. Lymph is a watery fluid that circulates within the lymphatic vessels and lymph nodes are found near these vessels. Within its capsule, a node is comprised of particular types of immune cells. These cells are mainly lymphocytes, which produce proteins that encapsulate and fight viruses and other germs. Lymph nodes are regional, and each group of them corresponds to a particular area of the body signifying abnormalities in that region. Some are directly under the skin while others are deep inside the body. However, even the most superficial lymph nodes are not usually visible or palpable unless they are swollen.
A wide variety of infections are the most common sources of swelling of the lymph nodes, for example, strep throat, ear infections, and mononucleosis. More serious medical conditions, such as HIV infection, lymphomas, other cancers, or lupus may cause swollen lymph glands. Symptoms associated with lymph node swelling and related diseases can include discomfort in the area of the swelling, fever, and fatigue. Keep in mind, not all swollen lymph nodes are abnormal.
Symptoms of swollen lymph nodes include:
As a general rule, swollen lymph nodes caused by infections, inflammation, or cancers can be painful or tender. Some benign causes of swollen lymph nodes may not cause discomfort.
Lymph nodes in various parts of the body may become swollen for different reasons. People can often see swollen lymph nodes
Swollen lymph nodes on the side of the neck or under jaw are the most common. They may signify an infection around that area, such as a tooth infection or abscess, throat infection, viral illness, or upper respiratory infection. Most of the causes of swollen lymph nodes in this area are benign; however sometimes swelling of these lymph nodes can also suggest a cancer in the head and neck area.
Swollen lymph nodes behind the ear or in the base of the skull may be consistent with an infection around the scalp or possibly an eye infection. The most common cause of swollen scalp lymph nodes are skin conditions affecting the scalp, such as dandruff, an abscess, or soft tissue infection.
The lymph nodes in the underarm are anatomically significant in breast cancer. They are often examined in patients undergoing evaluation for breast cancer. They also play a significant role in staging and predicting the outcome of breast cancer during removal of the cancer tissue from the breast. Numerous cancers including lymphoma and leukemia can cause enlargement of these lymph nodes. These lymph nodes can also become swollen due to trauma or an infection of the arm on the same side.
Enlarged lymph nodes above the collarbone are always considered abnormal. These generally suggest either a cancer of or an infection in a nearby region. This could include lung infection, lung cancer, lymphoma in the chest cavity, or breast cancer. Sometimes cancers that are more distant may seed these lymph nodes, such as genital cancers or colon cancer. Additionally, certain inflammatory conditions such as tuberculosis can cause swelling of these nodes.
Swollen lymph nodes in the groin may be ordinary in young people but they could also be the result of some sexually transmitted diseases, local infections, and infections of a lower extremity or genital cancers.
If you detect swollen lymph nodes, see your healthcare provider for an evaluation and possible treatment. Swollen lymph nodes closer to the surface of the body are typically diagnosed by a doctor feeling for areas known to have merging of lymph nodes, such as swollen lymph nodes under the arms or swollen lymph nodes in the sides of the neck. These swollen lymph nodes can be seen and palpated easily. Other times, deeper lymph nodes mat necessitate imaging studies such as a CT scan.
Keep in mind that there is no specific treatment for swollen lymph nodes. The underlying cause needs to be diagnosed and addressed, which may resolve the swollen lymph node. If an infection causes swollen lymph nodes, they may resolve in a few weeks. However, it is common for lymph nodes to remain enlarged an extended period after an infection has been treated. If swollen lymph nodes are a result of an autoimmune disorder, they may shrink in size during periods of remission and then enlarge again when the illness exacerbates. If the underlying cause is due to cancer, it depends on the type and stage of the cancer and whether it has spread to other parts of the body and the lymph nodes may remain enlarged for the length of the treatment.