A 27-year-old woman underwent laparoscopic Roux-en-Y gastric bypass. A retr
ocolic-retrogastric herniation of most of the small bower and later a gastr
ic perforation due to internal hernia at the mesenteric defect of the jejun
o-jejunostomy occurred. These unusual, but not rare, complications are dire
ctly related to the neoanatomy that follows gastric bypass and can lead to
rapidly progressing and life-threatening situations. Proper evaluation of c
linical signs and symptoms, early abdominal CT scan, and urgent operative i
ntervention are mandatory to achieve a successful outcome.