Lymph nodes are small, bean-shaped structures that are a part of the body’s immune system. Located throughout the body, including the neck, armpits, and groin, they are connected by lymphatic vessels. These nodes act as filters, trapping foreign substances like bacteria, viruses, and damaged cells, including cancer cells, as lymph fluid passes through them. Within the nodes, immune cells identify and eliminate these harmful invaders, defending the body against infection and disease.
Characteristics of Normal Lymph Nodes
Normal lymph nodes are typically small, pea-sized or less than 1 centimeter in diameter. When healthy, they feel soft and movable, and can be gently rolled under the skin. Their movability is a sign of health. You might feel them in areas like your neck, jaw, armpits, or groin, though many are too small or deep to be felt. They are typically not painful or tender.
Reasons for Lymph Node Enlargement
Lymph nodes commonly enlarge when the body fights an infection or inflammation. This occurs as immune cells within the nodes multiply to combat pathogens like bacteria or viruses. Common reasons for this temporary swelling include colds, flu, strep throat, ear infections, skin infections, or minor injuries near the nodes. While enlarged, these nodes often remain somewhat soft and may still be movable, though they may feel firmer. The swelling usually subsides as the infection resolves, typically within a few days to a few weeks.
When to Seek Medical Advice
Certain characteristics of enlarged lymph nodes warrant medical evaluation. A node that feels hard or rubbery, rather than soft, is concerning. Similarly, if a node is fixed or immovable when gently pushed, meaning it does not roll freely under the skin, it requires medical attention.
Nodes that grow rapidly or remain enlarged for several weeks (e.g., more than 2 to 4 weeks) without an obvious cause should also be checked. Also, seek advice if enlarged nodes are accompanied by symptoms like unexplained weight loss, persistent fever, night sweats, or fatigue. While some infections can cause tenderness, redness, or warmth around a node, persistent or severe symptoms also warrant medical advice. Consulting a healthcare professional is important if any of these characteristics are present, for proper diagnosis and to rule out serious underlying conditions.