Interposition of the gallbladder in the common hepatic duct: a rare dangerous anomaly. Case report

Anomalies of the gallbladder position in the biliary tract are rare, but they could be very dangerous during cholecystectomy. A 48-year-old man presented with a 2-week history of intermittent epigastric pain, scleral jaundice and elevation of liver function tests. After a magnetic resonance cholangiogram and an endoscopic retrograde cholangiogram with sphincterotomy, he was submitted to laparoscopic cholecystectomy, the conversion to laparotomy was decided for the suspect of gallbladder interposition. The anatomical anomaly was confirmed and a Roux-en-Y hepaticojejunostomy was executed, with end-to-side anastomosis between the confluence of the hepatic ducts and the fourth loop of jejunum, on a biliary stent. This catheter was removed in the tenth postoperative day; after cholangiography and CT abdominal scan the patient was discharged, without complications. The gallbladder interposition is a rare malformation which seems to arise from an embryonic anomaly occurring between the 4th and the 5th week and whose potential causes have not been detected. A similar outcome could be also determined by a Mirizzi syndrome, but in our case it is excluded because intra-operatively there was no inflammatory reaction that could justify the presence of a fistula between the gallbladder and the common hepatic duct. Once the gallbladder interposition is found, the surgical treatment consists in removing the gallbladder itself and the corresponding part of the common hepatic duct. The reconstruction is carried out by a Roux-en-Y hepaticojejunostomy with anastomosis at the hepatic hilum, positioning a biliary stent.