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What is appendicitis?

Appendicitis occurs when the appendix, an appendage (extension) of the colon, becomes inflamed (swollen) and infected. In many cases, an obstruction (blockage) within the appendix causes the infection, resulting in bacterial overgrowth. In 20 to 30 percent of children, the appendix ruptures and releases the infection into the abdominal cavity.

How common is appendicitis?

Appendicitis affects 80,000 children per year in the United States. It is most common in the second decade of life. Fifty percent of children will have a family history of appendicitis. Appendicitis is the most common cause for emergency abdominal surgery in childhood.

Ruptured appendicitis occurs in 30 percent of patients and is more common in children under five years old.

What are the symptoms of appendicitis?

Because the appendix is located in the lower right portion of the abdomen, the most important symptom is low abdominal pain. This often starts around the belly button and moves to the lower right side later. Other symptoms include: