Why do lymph nodes swell?

Why do lymph nodes swell?

What role does the lymph node play in the body?

Swollen lymph nodes usually occur as a result of infection from bacteria or viruses. Rarely, swollen lymph nodes are caused by cancer.

What is the function of the lymph node?

The lymphatic system is a network of organs, blood vessels, and lymph nodes.

Your lymph nodes, also called lymph glands, play a vital role in your body's ability to fight off infections. They function as filters, trapping viruses, bacteria and other causes of illnesses before they can infect other parts of your body.

Common areas where you might notice swollen lymph nodes include your neck, under your chin, in your armpits and in your groin.

In some cases, the passage of time and warm compresses may be all you need to treat swollen lymph nodes.

If an infection causes swollen lymph nodes, treatment depends on the cause.

Symptoms

Swollen lymph nodes are a sign that something is wrong somewhere in your body.

When your lymph nodes first swell, you might notice: Tenderness and pain in the lymph nodes, swelling that may be the size of a pea or kidney bean, or even larger in the lymph nodes.

Depending on the cause of your swollen lymph nodes, other signs and symptoms you might have include:

  • Runny nose, sore throat, fever and other indications of an upper respiratory infection
  • General swelling of lymph nodes throughout your body.
  • Hard, fixed, rapidly growing nodes, indicating a possible cancer or lymphoma
  • Fever
  • Night sweats

When to see a doctor

Some swollen lymph nodes return to normal when the underlying condition, such as a minor infection, gets better.

See your doctor if you're concerned or if your swollen lymph nodes:

  • Have appeared for no apparent reason
  • Continue to enlarge or have been present for two to four weeks
  • Feel hard or rubbery, or don't move when you push on them
  • Are accompanied by persistent fever, night sweats or unexplained weight loss

Seek immediate medical care if you're having difficulty swallowing or breathing.

Causes

The most common cause of swollen lymph nodes is an infection, particularly a viral infection, such as the common cold. However it may develop due to infection, immune system disorder and other causes.

Common infections:

  • Strep throat
  • Measles
  • Ear infections
  • Infected (abscessed) tooth
  • Mononucleosis
  • Skin or wound infections, such as cellulitis
  • Human immunodeficiency virus (HIV) — the virus that causes AIDS

Uncommon infections

  • Tuberculosis
  • Certain sexually transmitted infections, such as syphilis
  • Toxoplasmosis
  • Cat scratch fever

Immune system disorders

  • Lupus
  • Rheumatoid arthritis

Cancers

  • Lymphoma
  • Leukemia
  • Other cancers that have spread (metastasized) to lymph nodes

Other possible but rare causes include certain medications.

Complications

If infection is the cause of your swollen lymph nodes and isn't treated, an abscess may form. That is why, in order to avoid possible complications, it is recommended to consult a doctor in a timely manner.

 

Source:

https://www.mayoclinic.org/diseases-conditions/swollen-lymph-nodes/symptoms-causes/syc-20353902