Gallbladder duplication. Report of one case The duplication of the gallbladder is a rare malformation, seen in one every 3.000 necropsies. It is detected preoperatively by abdominal ultrasound. We report a 28 years old female consulting for abdominal pain. An abdominal ultrasound showed the presence of cholelithiasis and a complete septum in the gallbladder lumen. During surgery, a distended and inflamed gallbladder was found with a septum that divided it in two parts, and one biliary stone. There was also a double cystic duct. The pathological study confirmed the gallbladder duplication with inflammation.