A 15 year old previously healthy girl presented with 3 months of right upper quadrant abdominal pain, persistent nausea, and seven kg weight loss. Her exam revealed right upper quadrant and epigastric tenderness. Laboratory investigations, including bilirubin and liver enzymes, were normal. An abdominal ultrasound revealed a contracted gallbladder and a small ovoid structure in the right upper quadrant suggesting a possible choledochal cyst. Magnetic resonance cholangiopancreatography (MRCP) better defined these lesions as a 2.8 × 2 × 2 cm “ovoid” cystic structure (small arrow in Figure 1) and a gallbladder (larger arrow Figure 1). Onendoscopic retrograde cholangiopancreatography (ERCP) both structures filled with contrast with two completely separate cystic ducts attached to the common duct (Figure 2 and online-only images available at http://links.lww.com/MPG/A94).
She continued to be symptomatic and subsequently had a laparoscopic cholecystectomy. The intraoperative cholangiogram confirmed the ERCP findings. Accordingly, both gallbladders were removed. Examination of the resected specimens by histology confirmed two gallbladders and entirely separate cystic ducts (see online-only images).
Duplicated gallbladder is a rare anomaly of the biliary system with the reported incidence between 1 in 3800.1 The differential diagnosis for a cystic structure in the gallbladder region includes choledochal cyst, folded gallbladder, gallbladder diverticulum, focal adenomyomatosis, fibrous or vascular band and duplication of any other structure in the biliary system2. Although both ultrasound and MRCP are utilized in the evaluation of gallbladder anomalies, ERCP remains the gold standard to define this biliary tree abnormalitity3.
Causey et al. recently published a similar case and contend that defining the type of gallbladder duplication (based on the Harlaftis classification4 of multiple gallbladders) will aid in the selection of operative technique5. They reason that laparoscopy can be used for type 1 (the split primordial group, sharing a single cystic duct) and a traditional open approach should be used for type 2 (accessory gallbladder arising from separate primordium with two discrete ducts)5. The consensus from multiple case reports has been to only operate on symptomatic patients and remove both gallbladders given the risk of continued symptoms and non-functionality of either structure.