Classification of pancreaticobiliary maljunction and clinical features in children.

BACKGROUND

In 2015, the Committee on Diagnostic Criteria of the Japanese Study Group on Pancreaticobiliary Maljunction (PBM) proposed a classification of PBM into four types: (A) stenotic type, (B) non-stenotic type, (C) dilated channel type, and (D) complex type. To validate this classification and clarify the clinical features of the four types of PBM, a retrospective multicenter study was conducted.

METHODS

The study group of 317 children with PBM was divided into the four types of PBM. Clinical features, preoperative complications, operations, and postoperative pancreatic complications were evaluated.

RESULTS

All patients underwent excision of the extrahepatic bile duct. In type A, the age was younger and there was a higher incidence of cystic dilatation. Non-dilatation of the common bile duct was frequently seen in type B. Abdominal pain with hyperamylasemia was frequently seen in types B and C. In particular, the incidence of protein plugs and biliary perforation was high in type C (56.1% and 14.3%, respectively). The overall incidence of acute pancreatitis was 7.3%. Pancreatitis after excisional surgery was rare in the children in this study. Two patients with type D (0.6%) developed chronic pancreatitis postoperatively.

CONCLUSIONS

This proposed classification is simple and correlates well with clinical features.