An unusual cause of cholecystitis: heterotopic pancreatic tissue in the gallbladder.

Gallbladder localization of heterotopic pancreas (HP) is uncommon and very rarely gives rise to symptoms. Herein we report a case of HP found in the gallbladder neck presented with signs and symptoms of cholecystitis. The patient was a 40-year old male, suffering from epigastric pain, abdominal fullness and fever. On physical examination, the right upper abdomen was tender with a positive Murphy's sign. Ultrasonographic examination showed a hydropic gallbladder without stones and he underwent a cholecystectomy. Pathological examination revealed an intramural nodule (9 mm) in the neck region which is consisted of acini, ducts and islet cells of an aberrant pancreatic tissue. Although HP is encountered rarely in the gallbladder and is found incidentally during pathological studies, this case emphasizes that HP might cause symptoms and present clinically as cholecystitis. For this reason, in patients presenting with symptomatic gallbladder diseases, including cholecystitis without any other pathology, HP should be taken into consideration before it is diagnosed as "idiopathic".