72 year old Caucasian man who presented to the emergency department with sudden onset severe upper abdominal pain. Pain radiated to the back, with associated vomiting. No history of alcohol use. Past medical history includes acute pancreatitis, cholecystectomy for acute cholecystitis, hypertension and hyperlipidemia. There was no recent change in his medications. On examination, he was in distress, with elevated blood pressure and tachycardic. He had tenderness in his epigastrium, left lumbar region, no organomegaly and bowel sound were present. White Blood Count was elevated at 17,000, Hemoglobin was normal, Lipase and amylase were both elevated (15224U/L and 1054U/L), blood glucose was elevated at 217mg/dl. Calcium, triglycerides, bilirubin and liver enzymes were normal. A diagnosis of Acute Pancreatitis was made. CT of the abdomen showed edematous pancreas and large duodenal diverticula. Post cholecystectomy common bile duct was 1.1cm. He was commenced on IV fluid, IV opiates and insulin for blood sugar control. He became hypotensive, acidotic, in respiratory distress and was transferred to the intensive care unit. IV imipenem was added and he was fluid resuscitated. MRCP that was done showed acute pancreatitis, no obstructing calculi and a distended diverticulum measuring 4 x 3.4 cm with 0.4cm neck in the 2nd part of the duodenum. Patient has had 2 attempts at ERCP 5years prior when he had his first episode of acute pancreatitis. The ampulla was noted to be within the diverticulum and canullation was impossible. He improved and was discharged to follow up with gastroenterology for possible surgical or endoscopic management of his diverticulum.
The duodenum is the second to the jejunum as the common site of diverticula formation. It is rare below age 40 and it increases with age. Exact etiology is not known but occurs at weak spot such as the site of entry of common bile duct, pancreatic duct and perivascular connective tissue. 70‐75% are periampullary. Majority of the diverticular are asymptomatic. Complications arise when drainage in the neck is inadequate or the neck is narrow, these conditions favor inflammation and may lead to hemorrhage or perforation. Duodenal diverticulum has been implicated in the pathogenesis of acute and chronic pancreatitis. Mechanisms include compression of CBD, dysfunction of the ampulla or a poorly emptying diverticulum with a narrow neck. Biliary stone is also common in diverticular disease. This patient had a distended diverticulum with a narrow neck and an intradiverticular ampulla and he had no evidence of stone on his MRCP. Treatment is advocated only when pancreato‐biliary disease is recurrent and other etiology has been excluded. This can be done surgically or endoscopically.
For elderly patient with recurrent acute pancreatitis without obvious etiology, ruling out a periampullary diverticulum as an etiology is worthwhile before making a diagnosis of idiopathic acute pancreatitis.