Lethal small intestinal herniation through a congenital mesenteric defect.

A three-year-old boy with mild symptoms of an upper respiratory tract infection and recent onset vomiting collapsed at home. Resuscitative attempts in hospital were eventually unsuccessful. At autopsy an obstruction of the small intestine, with ischemia, was identified. It had been caused by strangulation of the small intestine through a congenital mesenteric defect. Moderate mesenteric lymphadenopathy, with enlarged lymph nodes in the region of the herniated small intestine, were associated with positive testing for human metapneumovirus and enterovirus. Transmesenteric hernias are a very rare form of internal herniation that have the highest risk of strangulation. Unfortunately in children the presentation may be relatively nonspecific with a precipitate decline towards the end. In the reported case it is possible that mesenteric lymphadenopathy may have contributed to intestinal entrapment by preventing spontaneous reduction.