Transmesenteric hernia due to double-loop formation in the small intestine: a fatal case involving a toddler.

We report a unique case of transmesenteric hernia resulting in death, which went undiagnosed during a recent hospital visit. The victim was a 2.5-year-old girl who - with the exception of chronic constipation - had no medical history. One night she complained of abdominal pains and was taken to a pediatric hospital where doctors performed an abdominal X-ray and echography. No significant findings suggesting bowel obstruction (e.g. air-fluid levels or dilation of the bowel) were obtained on examinations and bloody feces were not observed in this particular episode. As her abdominal pain gradually attenuated, the doctor allowed her to return home. A few hours later, she lost consciousness and expired despite resuscitation efforts attempted at an emergency hospital. A subsequent autopsy revealed that the small bowel had herniated through a defect in the mesentery resulting in two consecutive and inversely forming loops, in which each loop protruded on either side of the mesentery. This rare morphological anatomy seems to have progressed in a two-step process. The girl's mild abdominal pain was likely induced by herniation and formation of the first intestinal loop, followed by severe shock occurring when the subsequent intestinal segment invaginated into the same defect forming the second loop on the opposite side of the mesentery. This case illustrates the difficulty of diagnosing transmesenteric hernia due to the presentation of unspecific symptoms; especially in infants and toddlers. Furthermore, this report demonstrates the value of a complete autopsy in cases of sudden and unexpected deaths involving children.