Health Tip: Why You May Have Swollen Lymph Nodes

(HealthDay News) -- If you notice swollen areas around your neck, behind your head or ears, or under your arms, you might be feeling swollen lymph nodes. Lymph nodes are a key line of defense against infection.

The U.S. National Library of Medicine offers this list of possible reasons for swollen lymph nodes:

• An ear infection.

• The gum disease gingivitis.

• A tooth that is impacted or abscessed.

• Mononucleosis.

• A sexually transmitted disease, including HIV.

• Tonsillitis.

• Sores in the mouth.

• Tuberculosis.

• Rheumatoid arthritis.

• Certain cancers, such as leukemia, Hodgkin's disease or non-Hodgkin lymphoma.