Pancreaticobiliary maljunction (PBM) complicated with complete pancreas divisum

A rare pediatric case of pancreaticobiliary maljunction (PBM) with pancreas divisum is reported. The case showed extremely rare arrangement of the biliary tree and pancreatic duct; the common channel usually seen in PBM did not exist and the common bile duct was connected to the dorsal pancreatic duct via a dilated intermediary duct, in which a large protein plug had formed. The common bile duct was not dilated at all. All of these anomalies may have been caused by abnormal development of the ventral and dorsal pancreatic ducts at an early gestational age. We report a very rare pediatric case of pancreaticobiliary maljunction (PBM) complicated with pancreas divisum. In this case, the common bile duct showed a normal caliber and it was connected to the dorsal pancreatic duct through an intermediary dilated duct, which contained a protein plug that dammed up bile and pancreatic juice flow. This anomaly is very similar to type IIIc3 choledochal cyst, whose classification was addressed by Komi et al. (1), but it differed in the following point; in our case, the common bile duct did not connect to the duodenum through the ampulla of Vater (the common channel was absent) and bile was drained to the duodenum through Santorini duct. These quite rare anomalies might have been caused in the fetus by some kind of maldevelopment of the ventral and dorsal pancreatic ducts.