Case Report: Petersen Hernia, A Rare Cause of Bowel Ischemia

We report a case of a 52-year-old female with history Roux-en-Y gastric bypass (RYGB) three years ago prior to presentation to the emergency department (ED) with sudden onset epigastric abdominal pain with radiation into the back of two hours duration. She was diagnosed with bowel ischemia due to internal hernia through a Petersen’s mesenteric defect. A Petersen’s mesenteric defect is one of the three possible internal hernia sites and occurs between the Roux limb mesentery and a defect in the transverse mesocolon. Abdominal complaints are common in the emergency department with wide differential ranging from benign to emergent with need for immediate intervention. Thorough history and physical examination is an important component in managing and determining the acuity of patients presenting with abdominal pain as is demonstrated in this case in a patient with a history of RYGB without complications for 3 years following the operation.