Intussusception is the sliding of one part of the intestine into another.

Intussusception is caused by part of the intestine being pulled inward into itself. This can block the passage of food through the intestine. If the blood supply is cut off, the segment of intestine pulled inside can die.

The pressure created by the walls of the intestine pressing together causes:

• Decreased blood flow
• Irritation
• Swelling

The intestine can die, and the patient can have significant bleeding. If a hole occurs, infection, shock, and dehydration can take place very rapidly.

The cause of intussusception is not known, although viral infections may be responsible in some cases. Sometimes a lymph node, polyp, or tumor can trigger the problem. The older the child, the more likely such a trigger will be found.

Intussusception can affect both children and adults, although most cases occur in children ages 6 months - 2 years. It affects boys four times as often as girls.