It's normal to be worried or scared the first time you discover a swollen lymph node on your body. However, in a vast majority of cases swollen glands do not portend anything sinister – but you need to be able to recognize those that do.
The network of nodesYour lymphatic system is your best ally against infections. You have over 600 lymph nodes all across your body, connected one to another with special channels, forming complex chains. As your lymphocites, macrophages, and fibroblasts do their job killing and eating bacteria and viruses, the remaning waste and “dead bodies” of harmful microorganisms are trapped in lymph nodes and processed. White blood cells that have served their purposes are collected in the nodes, too, where they die and are recycled. Thus, lymph nodes are like tiny waste-processing plants, and each group of nodes drains those parts of the body that are located below it (more info here).
Why nodes swellWhenever your body is attacked by an infection, lymph nodes can be temporarily overwhelmed by work, simply because there is so much to process. As a result, they swell – this is called reactive lymphadenopathy (adenopathy simply means swelling). This is the most frequent reason: if your nodes are tender (i.e. hurt when touched) and soft, you probably have an infection. Another cause of swelling are autoimmune disease, for example:
- Sarcoidosis – an illness that can attack joints, lungs, and internal organs, sometimes causing pain but often no symptoms at all; it cannot be cured but often spontaneously goes into remission for years;
- Lupus – another incurable disease that can cause skin rash and a wide array of symptoms;
- Rheumatoid arthritis– a form of arthritis, cauising pain and deformation in the joints.
When to see the doctorIn a healthy person, none of the lymph nodes are visible or palpable, but an infection can cause them to enlarge to the size of a golf ball! Location and accompanying symptoms can say a lot about the cause. You should definitely go to the doctor if your lymph nodes:
- Swell in absence of any other symptoms;
- Grow rapidly in size;
- Persist for over 2 weeks;
- Fell firm, painless, or rubbery to the touch;
- Swell accompanied by one or more of the folloing: fever, fatigue, itching (in any part of the body), unexplained weight loss.
Causes by areaSome infections (like HIV, mononucleosis or toxoplasmosis) can cause glands all over your body to swell, but most only act on a particular group:
- Behind the ear: often infections of the scalp (like dandruff) or teeth
- Neck – Infections of the throat and lungs
- Above the collarbones – always suspicious! Can mean mononucleosis, toxoplasmosis, sarcoidosis, extrapulmonary tuberculosis, but also Hodgkin lymphoma. Go to the doctor!
- Under armpits: if less than 2 cm – usually nothing serious, but can be related to arm infections or breast cancer.
- Groin – normally benign in young people, very rarely malignant, can stem from genital infections and leg injuries.
As you see, almost anything can cause your nodes to swell. For a diagnosis, the doctor will order blood tests, ultrasound, or a biopsy. Don’t get alarmed needlessly: most probably you are fine. However, don’t postpone your visit to the doctor, either – your lymph nodes may be trying to tell you something important.