2527 Posterior Perforation Arising From a Duodenal Diverticulum

Abstract

INTRODUCTION: Duodenal diverticulums (DD) are present in 6-22% of the general population on autopsy, however, it is uncommon to be symptomatic. We present a rare case of a patient who developed a posterior perforation of a duodenal diverticulum. CASE DESCRIPTION/METHODS: An 82-year old male presented with a chief complaint of weakness. On admission, the patient was found in septic shock, thought to be from pneumonia and started on antibiotics. Due to a lack of bowel movements over several days, a KUB was ordered and showed ileus of the proximal small bowel. The following day he developed large melanotic stools and laboratory workup revealed a hemoglobin of 5.6. The patient was resuscitated and underwent an endoscopy. A large ulcer covering 50% of the duodenal circumference with a large tract was discovered (Figure 1). A follow-up CT abdomen (Figure 2) demonstrated fluid and edema surrounding the pancreas, pneumoperitoneum, and fluid collection in the third portion of the duodenum. Additionally, a UGI with gastrografin (Figure 3) showed a diverticulum in the third portion of the duodenum with extravasation of contrast into the retroperitoneum indicating perforation. Surgery revealed a diverticulum of the second portion of the duodenum. The perforation was found to lead into the retroperitoneal space and directly into the body of the pancreas. Unfortunately, the patient would develop multi-organ failure secondary to fulminant septic shock and passed away. DISCUSSION: It is uncommon for duodenal diverticulums to be symptomatic with only about 10% doing so. They can present with upper abdominal pain, obstruction, ulcer, diverticulitis, perforation, and pancreatitis. Bleeding can occur but is rare. DD can be classified as primary acquired diverticula or secondary diverticula, which is caused by peptic ulceration. They are thought to be caused by herniation of the mucous membrane through the muscular coat at sites weakened by the passage of blood vessels or aberrant growth of pancreatic tissue. Perforations associated with duodenal diverticulums are typically located in the anterior portion of the duodenum or stomach however, spontaneous non-traumatic posterior perforation is a distinct clinical rarity, not commonly encountered. Posterior perforations tend to present late due to insidious onset. These ulcers perforate into the retroperitoneal space or lesser sac. Local inflammatory reaction and fibrosis of the adherent retroperitoneal space tend to seal off these perforations which may explain their vague symptoms.