2545 If Any Doubt, Rule It Out: Having a High Clinical Suspicion for Paraduodenal Hernia

Abstract

INTRODUCTION: Paraduodenal hernia (PDH) is a type of internal abdominal hernia (IH), a rare entity with a reported incidence of 0.2-0.9% on autopsy. Though typically asymptomatic, it is an important diagnosis to consider when suspicious for bowel obstruction as mortality can reach up to 20%. We report a case of a 46 year old female with vague abdominal complaints who had a PDH. CASE DESCRIPTION/METHODS: A 46 year old female with a history of questionable bowel obstruction and hysterectomy, presented with 3 days of abdominal pain, nausea, and vomiting. She had decreased stool caliber over the previous week with no bowel movements, and inability to pass gas for 2 days. The patient reported having a similar episode 2 years prior that resolved with nasogastric tube decompression. Imaging was unrevealing and an etiology for her symptoms was not identified. On admission, her vitals were stable and her physical exam was positive for abdominal distention, high-pitched bowel sounds, and tenderness to palpation in the right upper quadrant. Labs were remarkable for leukocytosis with a WBC of 13.6. CT abdomen/pelvis with contrast revealed an internal hernia with small bowel and mesentery extending lateral to the right colon through a defect in the ascending mesocolon (Figure 1). The patient's symptoms persisted so she was taken to the operating room for a diagnostic laparoscopy. A PDH was repaired, and her symptoms subsequently improved. DISCUSSION: PDH is rare and difficult to diagnose, but is an important entity to consider in bowel obstruction. Though responsible for bowel obstruction in 5.8% of patients, early diagnosis is crucial as there is an overall 20% mortality rate, 50% mortality if the bowel is strangulated, or nearly 100% if ischemic. The etiology of PDH is widely debated, but the most accepted theory is an error in intestinal rotation and fixation causing entrapment of the small bowel between the mesocolon and posterior abdominal walls. In adolescents, it is thought to arise from congenital defects. In adults, the major risk factor is prior surgical intervention, including Roux en Y bypass, peripheral adhesive bands, laparoscopic surgeries, or gynecologic surgeries. Clinical diagnosis of PDH is extremely challenging as abdominal exams and radiologic studies are subtle or negative until patient becomes acutely ill. Compared to other IHs, symptoms and radiologic findings in PDHs may be particularly subtle. Having a high clinical suspicion is crucial given high mortality rate of complications.