Introduction: Duct-to-duct (DD) anastomosis in pediatric liver transplantation (Ped-LT) is used only in older children with preserved extrahepatic bile duct. Contrary to the adult population, the outcome of this type of reconstruction is poorly reported. The aim of this study was to investigate the incidence of biliary complications in Ped-LT with DD and to identify associated risk factors.
Methods: We performed a retrospective study of our experience with duct-to-duct biliary reconstruction in pediatric patients who received a liver transplant between 2014 and 2024. Only DD patients were included, they patients were divided in to groups, with complication (C-DD) and without complications (NC-DD). Donor and recipient and donor data, donation variables, operative details, treatment of complications and postoperative follow-up were reviewed and analyzed.
Results: Of 378 transplants, DD anastomosis was performed in 22 cases (14 whole liver, 5 reduced, and 3 combined liver-kidney). Biliary complications occurred in 4 (18.2%), including three cases of anastomotic stricture (one following ischemic cholangiopathy) and one case of bile leakage. The median time for complications to develop was 4 days (IQR, 1-1650 days). Biliary leak responded to conservative treatment, while anastomotic strictures required endoscopic retrograde cholangiopancreatography (ERCP) with balloon dilatation and stent placement. The median number of endoscopic explorations was 2 (IQR, 1-4), with a median of 2 dilations (IQR, 1-3) and the placement of 1 biliary stent/patient (IQR, 0-2). The only identified risk factor was the surgical time, that was lower in NC-DD group compared to the C-DD (258±167.2 vs 468.4±81.2, p=0.001). Blood transfusion was higer, although not significant in C-DD group (3037.5±1719 vs 1114.3±826). No deaths were reported and only the patient with ischemic cholangiopathy required retransplantation. Median follow-up was 48 months (IQR, 14-81 months). 
Conclusion: Most complications related to DD reconstruction resolved with conservative treatment or ERCP. Prolonged surgical time was identified as the only significant factor associated with the development of biliary complications, while blood loss may also contribute to their occurrence. Further studies with larger sample sizes are needed to show definitive conclusions.