Adenomyomatous hyperplasia of the ampulla of Vater presenting as acute pancreatitis.

We report an interesting and rare case of a man with adenomyomatous hyperplasia of the ampulla of Vater presenting as acute pancreatitis, which to our knowledge, is only the second reported case in the English literature. The patient presented with an acute onset of abdominal pain, nausea and vomiting, without fever, chills or rigours. CT of the abdomen revealed changes of acute pancreatitis with a peripancreatic adenopathy, and abdominal ultrasound revealed a slightly hyperechoic and oedematous head of the pancreas, consistent with acute pancreatitis. Endoscopic retrograde cholangiopancreaticography revealed an ampullary lesion. Pathology of the ampullary lesion revealed an inflammatory polyp. Endoscopic ultrasound with endoscopic mucosal resection of the lesion revealed an adenomyomatous hyperplasia. The patient recovered well postendoscopic resection without recurrent pancreatitis or cholestasis.