Lymph nodes are small, bean-shaped structures that are part of the body’s defense system. While usually unnoticed, their swelling or pain signals an active bodily response. Understanding their role helps clarify why this pain occurs.
The Lymphatic System and Its Nodes
The lymphatic system plays a significant role in the body’s immune and circulatory systems, acting as a crucial network for maintaining fluid balance and defending against illness. It consists of lymphatic vessels, which are tubes forming a complex network throughout the body, carrying a clear fluid called lymph. Lymph is essentially extra fluid that drains from cells and tissues, containing proteins, minerals, fats, and also potentially damaged cells, cancer cells, and germs.
Lymph nodes are small, kidney-shaped organs along these lymphatic vessels. They function like filters, cleansing the lymph as it passes through them. Within these nodes are immune cells, including lymphocytes and macrophages, which work to identify and destroy foreign invaders such as bacteria, viruses, and abnormal cells. Common areas where enlarged nodes can be felt include the neck, under the chin, armpits, and groin.
Causes of Painful Lymph Nodes
Pain in lymph nodes indicates inflammation or rapid swelling, often from an active immune response. The pain results from the stretching of the node’s fibrous capsule as immune cells and fluid accumulate. This tenderness signals the body is fighting an infection or other challenge.
Infections are the most frequent cause of painful, swollen lymph nodes. Viral infections like the common cold, flu, sinus infections, or mononucleosis often swell neck nodes. Bacterial infections, including strep throat, cellulitis, or an abscessed tooth, can also enlarge and pain lymph nodes near the infection site. For example, a leg cut might swell groin nodes.
Beyond infections, autoimmune conditions like lupus and rheumatoid arthritis can cause lymph node pain and swelling. These diseases involve the immune system mistakenly attacking healthy body tissues, which can result in widespread inflammation. Swelling may accompany other symptoms like joint pain, fatigue, or skin issues. Less commonly, some medications or immunizations can temporarily cause lymph node swelling.
Less commonly, painful lymph nodes can indicate serious conditions like lymphoma or leukemia. Pain may occur if enlarged nodes press on surrounding nerves. However, cancerous lymph nodes are often hard, fixed, and may not be painful, unlike those swollen from infection.
When to Consult a Healthcare Professional
While painful lymph nodes often respond temporarily to minor infections, certain signs warrant medical evaluation. Consult a healthcare provider if swollen lymph nodes persist over two to four weeks or continue to grow. Nodes that feel hard, rubbery, or are fixed and do not move when pressed are also concerning.
Systemic symptoms with swollen lymph nodes also prompt a doctor’s visit. These include unexplained weight loss, persistent fever, or night sweats. Swollen nodes above the collarbone or in the armpit, without obvious local infection, also require investigation. Additionally, if pain is severe, or swelling causes difficulty breathing or swallowing, seek immediate medical attention.