Intussusception is a condition in which one portion of intestine collapses into another. The potentially life-threatening situation is the most common source of intestinal obstruction in children between the ages of 3 months and 6 years. When detected early, intussusception is highly treatable.

During intussusception, one portion of the intestine slides into another, much like the pieces of a telescope. Inflammation follows, obstructing the intestine and blocking blood flow in the affected area. Intussusception can occur in the small intestine, the large intestine or the area between these two structures.

Patients with intussusception typically experience sudden, sharp intestinal pain. In children, this may be followed by loud screaming and drawing of the knees to the chest, which often relieves symptoms temporarily. This initial pain is followed by vomiting and diarrhea, bloody stool and fever. Many patients will develop a sausage-shaped mass in the upper mid-abdomen.

In most cases, the cause of intussusception is unknown. This is particularly true of intussusception that affects children. Previously, some cases of intussusception were associated with use of a vaccine designed to prevent rotavirus, which causes intestinal infection (gastroenteritis). However, use of this drug was discontinued in children and a new vaccine that is not associated with increased intussusception risk was recently approved in its place.

Before diagnosing intussusception, a physician will perform a physical examination and compile a medical history. The physician may be able to feel a swollen, tender mass in the affected part of the intestine.

An x-ray procedure called a barium enema is often used to both diagnose and treat intussusception. During this procedure, patients are given an enema in which a liquid containing a chalky substance called barium is inserted into the rectum. This helps highlight internal structures so that abnormalities are easier to detect. Air is also inserted into the rectum to try to push the collapsed portion of the intestine back to its proper place. If this technique fails to treat intussusception, surgery may be necessary.