In infants, intussusception usually arises from unknown causes. In older children, polyps, hemangioma, lymphosarcoma, lymphoid hyperplasia, Meckel’s diverticulum, or alterations in intestinal motility may trigger the process. In adults, intussusception most commonly results from benign or malignant tumors (65% of patients); other possible causes include polyps, Meckel’s diverticulum, gastroenterostomy with herniation, and an appendiceal stump.

In addition, studies suggest that intussusception may be linked to viral infections because seasonal peaks are observed—in the spring and summer, coinciding with peak incidence of enteritis, and in midwinter, coinciding with peak incidence of respiratory tract infections.

Necrosis can result with hemorrhage. Without prompt treatment, strangulation of the intestine may occur, with gangrene,
shock, perforation, and peritonitis. These complications can be fatal.

If the patient is an infant or child, the history may reveal intermittent attacks of colicky pain. Typically, this pain causes the child to scream, draw his legs up to his abdomen, turn pale and diaphoretic, and possibly grunt. Parents may report that the child vomits—initially, stomach contents and, later, bile-stained or fecal material.