There are many causes of enlarged lymph nodes in the neck. Some can be quite serious, while others may be just an indication of mild illness. Sometimes they go away without any treatment. A physician can decide if the nodes are worth examining further through biopsies and other medical tests.
Many types of infections can cause enlarged lymph nodes in the neck. The most common are infections of the throat (like tonsillitis) or the ear.
Mononucleosis is one of the most common viruses causing swollen lymph nodes in the neck. Other viruses, including the common cold, can also cause the nodes to enlarge.
Sometimes enlarged lymph nodes in the neck can be a signal of cancer. Leukemia, lymphoma and Hodgkin's disease are the most common cancers with this symptom.
Dental problems, such as an impacted or abscessed tooth, can cause the lymph nodes in the neck to swell.
There are some immune and autoimmune disorders that cause neck lymph nodes to enlarge. Rheumatoid arthritis and HIV are two examples.
Lymph nodes in the neck play a role in the body's fight against infection. If they are extremely enlarged or do not go down on their own, they need to be examined by a doctor.