Lymph nodes are small, bean-shaped glands that play a role in the body’s immune system. They function as filters, trapping viruses, bacteria, and other harmful substances before they can spread. Within these nodes, immune cells such as lymphocytes identify and fight off infections. When lymph nodes swell, it often indicates immune cells are actively combating an infection or illness.
Where to Find and Feel Swollen Lymph Nodes
Lymph nodes are distributed throughout the body, but certain areas are more accessible for self-assessment. Common locations include the neck, armpits, and groin. In the neck, nodes are present under the jaw, along the sides, and at the back of the neck, near the hairline.
To check for swelling, gently use your fingertips to feel these areas. Normal lymph nodes are small, soft, and movable, feeling like tiny peas or beans beneath the skin. When they swell, they become noticeably larger, sometimes reaching the size of a grape or small plum.
A swollen lymph node may feel firm or rubbery and can be tender or painful to the touch. They can also feel fixed in place rather than easily movable. Comparing one side of your body to the other can help identify any asymmetry or unusual lumps.
Why Lymph Nodes Swell
The most common reason for swelling is an infection. When the body encounters a pathogen, nearby lymph nodes become activated, increasing immune cell production and fluid accumulation. This activation causes the nodes to enlarge as they filter and combat microorganisms.
Common infections include upper respiratory infections like the common cold or flu, strep throat, and ear infections. Skin infections near a lymph node cluster, such as a cut or insect bite, can also lead to localized swelling. Other viral infections, like mononucleosis or chickenpox, often cause widespread enlargement.
Less common causes include inflammatory conditions, such as rheumatoid arthritis or lupus, where the immune system attacks healthy tissues. In rare instances, they can indicate more serious conditions, including cancers like lymphoma or leukemia, or the spread of cancer. Most instances are due to benign, self-limiting infections.
When to Consult a Doctor
Most swollen lymph nodes are benign and resolve on their own, but some characteristics warrant medical evaluation. Consult a healthcare provider if a swollen lymph node persists for more than two to four weeks without improvement. Nodes that continue to grow, or become very hard and fixed in place rather than movable, also require attention.
Seek medical advice if the swelling is accompanied by other concerning symptoms. These include unexplained weight loss, night sweats, or a persistent fever. Nodes that appear without obvious signs of infection, such as a sore throat or skin wound, should also be evaluated. Prompt medical attention ensures proper diagnosis and timely management.
Medical Evaluation for Swollen Lymph Nodes
Medical evaluation for swollen lymph nodes begins with a thorough physical examination. The doctor will carefully feel the affected lymph nodes, assessing their size, tenderness, consistency, and mobility. They will also inquire about your medical history, recent infections, medications, and other symptoms.
Based on the initial assessment, further diagnostic tests may be recommended to determine the cause of the swelling. Blood tests are often among the first steps, including a complete blood count (CBC) to check for infection or other abnormalities. Specific infection markers or antibody tests may also be performed to identify particular viruses or bacteria.
In some cases, imaging studies like an ultrasound or computed tomography (CT) scan might be ordered to get a clearer view of the lymph nodes and surrounding tissues. If the cause remains unclear or a serious condition is suspected, a biopsy may be necessary. During a biopsy, a small tissue sample is removed and examined under a microscope for a definitive diagnosis.