What swollen lymph nodes are
Lymph nodes are small structures of the immune system. They filter lymph and meet infection. You can most often feel them in the neck, under the jaw, behind the ears, in the armpits and in the groin. When there is inflammation nearby, the nodes react and swell, and sometimes become tender. They are often called swollen glands, which is not quite accurate, but it is how many people search for them. Swollen lymph nodes are not a diagnosis. They are a sign that the immune system is working or that there is a source of inflammation close by.
Swollen glands in the neck and under the jaw
This is the most common place. The cause is usually an infection of the throat, nose or ears: a cold, tonsillitis, an inflamed tooth or gums. A sore throat (see sore throat) and a fever (fever) may come with it. Swollen nodes in front of the ears and puffy cheeks can occur with mumps, and swollen nodes at the back of the head and neck with a rash can occur with rubella. After recovery the nodes usually shrink within a week or two, but may stay slightly noticeable for longer.
Swollen lymph nodes in the armpit and groin
Nodes in the armpit most often react to a skin infection, a cut or scratch on the arm or hand, or inflammation in the breast area. In the groin they react to infections of the skin and genitals, urinary infections and cuts on the legs. If the cause is clear and passes, the nodes shrink with it. If a node in these areas keeps growing for no obvious reason, see a doctor.
Swollen lymph nodes in a child
In children lymph nodes react to infection especially often, and small, movable nodes in the neck are common even in healthy children. They are most often linked to ordinary viral infections. Take your child to a pediatrician if the nodes are growing, have not shrunk after a week or two, are painful or red, or if the child eats poorly, is listless or has a fever.
When swollen nodes are not just a simple infection
Less often nodes swell with tuberculosis, autoimmune diseases, a reaction to a medicine and, very rarely, blood diseases and tumours. Be concerned if a node is hard, does not move when you press it, is painless, keeps growing, lasts longer than a week or two with no clear cause, sits above or below the collarbone, or comes with night sweats, weight loss and fever. For weakness and quick tiredness see weakness and fatigue.
What you can do before seeing a doctor
- Rest and drink enough fluids, as with any infection.
- If a node is sore, a painkiller is chosen by age and how you feel; for children, ask a pediatrician.
- Do not press, massage or heat the node: it does not speed recovery and can make inflammation worse.
- Look for a nearby source of infection: a bad tooth, a cut, a scratch or inflamed skin.
- Keep an eye on the size: measure it and note whether it shrinks within one to two weeks.
How a doctor looks for the cause
The doctor will feel the nodes and judge their size, firmness, mobility and tenderness, examine the throat, teeth and skin, and ask about fever, weight, sweating and contact with sick people. Usually a blood count and an ultrasound of the lymph nodes are ordered, and if needed a chest X-ray or tests for infections. To find out the nature of a node the doctor may refer you for a biopsy. Antibiotics are given only for a bacterial cause: they do not help a viral infection.