Heterotopic gastric mucosa in a duplicate gallbladder

A 7-year-old girl presented with recurrent acute pancreatitis. Detailed investigations, including endoscopic retrograde cholangiography, suggested a poorly defined biliary tract abnormality. At laparotomy, this was discovered to be a duplicate gallbladder each with a separate cystic duct but contained within a single serosal envelope. Both gallbladders were removed, and histologic examination found the inferior organ to be lined by heterotopic fundic-type gastric mucosa. Despite the absence of any remaining structural biliary abnormality and no evidence of residual ectopic gastric mucosa, the patient experienced a few further episodes of self-limiting mild acute pancreatitis during the following 3 years. The presence of heterotopic gastric mucosa in a duplicate gallbladder has not been described previously.