Case report of an annular pancreas

A 34-year-old female came into the emergency room complaining about abdominal pain associated with nausea. She reported no other symptoms.

On admission, an abdominal ultrasound was conducted, which showed multiple mobile stones inside the gallbladder with mild choledochal dilation (Figures 1 and 2). The patient underwent surgery the next day. However, the patient continued to complain about abdominal pain. Thus, an abdominal magnetic resonance was performed for further evaluation, revealing pancreatic tissue surrounding the second part of the duodenum causing extrinsic compression seen in T2 sequences (Figures 3A and 3B).

An endoscopic study was also conducted, showing extrinsic compression of the duodenum of less than 50%, erosion of the gastric mucosa, and signs of duodenitis (Figures 4, 5, 6, and 7). The findings in the esophagogastric duodenal series were gastroesophageal reflux grade II, thickening of the gastric folds, and compression of the second part of the duodenum (Figures 8 and 9).

Background

Annular pancreas is a rare congenital malformation at 6-7 weeks of gestation and rarely detected in adults. If the fusion of the ventral and the dorsal pancreas is abnormal, all or part of the pancreas tissue will surround and compress the duodenum, causing complete or incomplete duodenal obstruction; the latter of which is more common.

Clinical perspective

Adult-type annular pancreas is associated with pancreatitis, malignant tumours of the digestive system, and duodenal ulcers leading to a duodenal stricture. A total of 70% of patients show abdominal pain, 60% present nausea and vomiting, and a few with jaundice. [1]

Imaging perspective

Annular pancreas can be diagnosed radiologically by identifying pancreatic tissue surrounding the duodenum in T1 and T2 sequences. [2]

Outcome

An asymptomatic patient with annular pancreas does not need any treatment. Nevertheless, a duodenojejunostomy is recommended for patients with severe duodenal stricture and pancreatoduodenectomy should be considered for patients with chronic pancreatitis, pancreatic duct stones, or malignant tumors.[3][4]

To date, medical treatment for gastritis and gastroesophageal reflux has been administered to the patient. However, if the patient shows no signs of improvement, the next step would be to pursue surgical treatment (duodenojejunostomy). Prognosis in most cases is favourable, depending on the malignant findings associated.[5]