Unexpected death due to intestinal obstruction by a duplication cyst in an infant.

An 11-month-old female infant died at home after being diagnosed as having gastroenteritis. Autopsy examination revealed a distended distal ileum filled with a large amount of watery contents, and a 3 cm x 3 cm x 4 cm cyst at the ileocecal part of the cecum that was histologically consistent with a duplication cyst. The cause of death was determined to be acute dehydration due to intestinal obstruction caused by a duplication cyst. This case indicates that intestinal obstruction by a duplication cyst should be recognized as a cause of unexpected death in infants.