Abnormal Pancreaticobiliary Junction in Children: Frequency on Magnetic Resonance Cholangiopancreatography and Associated Pancreaticobiliary Diseases.

Background and aims: There is scarcity of data on the prevalence of abnormal pancreaticobiliary junction (APBJ) in children. This study aimed to determine the frequency and clinical significance of APBJ including pancreas divisum (PD) and common channel (CC) using magnetic resonance cholangiopancreatography (MRCP).

Materials and methods: Single-center, retrospective study of MRCPs in children aged 0 to 18 years from 2012 to 2022. Two independent readers assessed PBJ visibility, abnormalities (PD, CC, other), and CC length. Findings were correlated with presenting diagnoses of choledochal cyst, biliary lithiasis, and pancreatitis.

Results: A total of 631 MRCPs were included (46.8% females; mean age: 12 ± 5 y). The PBJ was visible in 85.7% of cases. APBJ was observed in 114/631 (18.1%) children, with PD in 47 (7.4%) cases and CC in 61 (9.7%) cases, with an average length of 9 mm (range, 3 to 22 mm). There was a significant inverse association between PD and biliary lithiasis (P = 0.02). There was no association between PD and pancreatitis. CC was significantly associated with choledochal cyst (P < 0.0001), pancreatitis (P = 0.004) and biliary lithiasis (P < 0.0001), with 21/61 (34.4%) of CC demonstrating stones within (median age: 3.8 y). The CC length was also significantly associated with complications (P = 0.014), with complication-free cases having a median length of 7 mm (range, 4 to 8) compared with 11 mm (range, 3 to 25) in complicated cases.

Conclusion: APBJ is a frequent finding on pediatric MRCP. CC is significantly associated with choledochal cyst, pancreatitis and lithiasis, and may show stones within them, particularly in small children. PD is inversely associated with biliary lithiasis. Careful PBJ assessment is important in children.