Why are swollen lymph nodes a sign of infection?

Lymph nodes are small, bean-shaped organs that are part of the body's immune system. They are located throughout the body, but are especially concentrated in the neck, armpits, and groin. Lymph nodes act as filters, trapping bacteria, viruses, and other foreign particles that enter the body. When these particles are trapped, the lymph nodes can become swollen and tender.

Swollen lymph nodes are often a sign of infection. This is because when the body is fighting an infection, the lymph nodes work harder to filter out the harmful particles. As a result, they can become inflamed and swollen.

Swollen lymph nodes are most commonly caused by the following infections:

- Colds and flu

- Strep throat

- Tonsillitis

- Ear infections

- Skin infections

- HIV

- Tuberculosis

In some cases, swollen lymph nodes can also be a sign of a more serious medical condition, such as cancer. If you are experiencing swollen lymph nodes that do not go away after a few weeks, it is important to see a doctor to rule out any underlying medical problems.

In addition to infection, there are a few other potential causes of swollen lymph nodes, including:

- Allergies: Swollen lymph nodes can be a symptom of an allergic reaction to something.

- Medications: Certain medications, such as penicillin and sulfa drugs, can cause lymph nodes to swell.

- Autoimmune disorders: Conditions such as lupus and rheumatoid arthritis can cause the lymph nodes to swell.

- _Some cancers - including lymphoma, leukemia, and breast cancer:_ Lymph nodes in any part of the body might be affected when cancer spreads in this way through body channels.