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Understanding Tonsillitis - the Basics

What Is Tonsillitis?

The tonsils are two masses of lymphatic (immune system) tissue located at the back of the throat. They produce antibodies designed to help you fight respiratory infections. They are small at birth and gradually increase in size until age 6 or 7. Then they shrink, but do not disappear. When these tissues themselves become infected, the resulting condition is called tonsillitis.

Tonsillitis most commonly affects children between the ages of 3 and 7, when tonsils may play their most active infection-fighting role. As the child grows and the tonsils shrink, infections become less common. Tonsillitis is usually not serious unless a tonsillar abscess develops. When this happens, the swelling can be severe enough to block your child's breathing. Secondary ear infections and adenoid (swellings at the back of the nasal cavity above the tonsils) problems are other complications.

What Causes It?

Most tonsil infections in elementary school-age children are caused by viruses. The likely viruses include those that cause the common cold, influenza (flu) viruses and the Epstein Barr Virus (EBV), which causes mononucleosis. Some types of bacteria can also cause tonsillitis. The most common bacteria are the same organisms which cause strep throat. Tonsillitis is due to strep throat in kids only about 30% of the time, and less so in adults.

These are transmitted by casual contact with others - like droplets in the air from sneezing. The tonsils try to fight viruses and bacteria that enter through our mouth and nose. The result is an infection in the tonsils. This infection can swell and become inflamed and painful.

WebMD Medical Reference

Reviewed by Mark N. Saberman, MD on November 25, 2008
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