Obstructive internal hernia caused by mesodiverticular bands in children Two case reports and a review of the literature

Introduction: The mesodiverticular band (MDB) is an embryologic remnant of the vitelline circulation, which carries the arterial supply to the Meckel diverticulum. In the event of an error of involution, a patent or nonpatent arterial band persists and extends from the mesentery to the apex of the antimesenteric diverticulum. This creates a snare-like opening through which bowel loops may herniate and become obstructed. This report describes 2 rare cases of small bowel occlusion owing to an internal hernia caused by a MDB. Cases: Case 1 was a 5-year-old boy who presented to our Emergency Department with colicky abdominal pain diffused to all abdominal quadrants. He also had 5 episodes of emesis, the last with bilious vomiting. Case 2, a 12-year-old boy, presented to our Emergency Department complaining of colicky abdominal pain. He had 2 episodes of nonbilious emesis. On physical examination, both children showed distension and tenderness of the abdomen and abdominal x-ray and ultrasound confirmed an occlusive picture without an apparent etiology. In case 1, an urgent laparotomy was performed and the MDB was ligated and cut, whereas in case 2 diagnosis and excision were performed in laparotomy. In both patients, there was a positive clinical evolution. Conclusion: Although MDB causing internal hernia is very rare, it should be considered in patients with a clinical picture of small bowel obstruction. In these cases, early surgery is important to prevent strangulation and gangrene of the bowel and to avoid dramatic events. Moreover, laparoscopy seems a safe and effective technique in these patients, especially in children with mild abdominal distention without surgical or trauma history, highlighting that further studies on the value of laparoscopy for the treatment of small bowel obstruction in pediatric patients are urgently needed. Abbreviations: MD = Meckel's diverticulum, MDB = mesodiverticular band, SILS = single incision laparoscopic surgery.