Introduction: Biliary congestion and dilatation of intrahepatic segmental bile duct (SBD) are major biliary complications of Roux-en-Y hepaticojejunostomy (RYHJ) in pediatric liver transplantation (LT) with partial graft. SBD dilatation occurred in the bile duct of the main biliary tree (MBT) or in the bile duct not in continuity with the main biliary tree (non-MBT). SBD dilatation causes elevation of liver function test (LFT) and may cause bile leakage after LT. We discussed these complications based on our experience with pediatric LT.
Methods: Pediatric patients who underwent LT between April 2010 and March 2021 in our institute were gathered. Patients who underwent LT with whole liver graft, or duct to duct anastomosis for biliary reconstruction or died within 1 year after LT were excluded. The patients were divided into those with and without the placement of an internal short stent across the anastomoses, and those with and without ligation of non-MBT from B1 or B4. The LFTs including serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were evaluated at 1, 3, 6 months, and 1 year after LT. Contrast-enhanced abdominal computed tomography was performed at 1, 3 months and 1 year after the LT, and a bile duct more than 3 mm in diameter was defined as dilated. The relationship between postoperative LFT and MBT or non-MBT dilatation, and the relationship between biliary reconstruction methods and the occurrence of those biliary dilatations were analyzed.
Results: 57 cases were included; SBD dilatation was present in 15 cases (26%), including 6 (11%) with MBT dilatation, 10 (18%) with non-MBT dilatation, and 1 with both.
In patients with non-MBT dilatation, AST and ALT at 3 months after LT were significantly higher than patients without dilatation. However, AST and ALT at 1 months, 6 months, and 1 year after LT were the same in both patients. These results suggested that non-MBT dilatation caused a temporal elevation of LFT, which returned to normal by 6 months after LT.
In patients with MBT dilatation, AST and ALT at 1 and 3 months after LT were the same as patients without MBT dilatation. However, AST and ALT at 6 months and 1 year after LT were significantly higher than patients without dilatation. Those results suggested that elevated LFT persisted for 1 year after LT in patients with MBT dilatation.
The occurrence of MBT dilatation was significantly correlated with the presence of the internal short stent across the anastomoses (placed: not placed = 30%: 7%, p=0.039). The occurrence of non-MBT dilatation was significantly correlated with ligation of non-MBT from B1 or B4 (ligated: not ligated = 44%: 13%, p=0.031).
Conclusion: The placement of the internal short stent was correlated with MBT dilatation which could be explained by compression or obstruction of the anastomosis by the stent. The dilatation of non-MBT causes temporal elevation of LFT, while the dilatation of MBT causes persistent LFT abnormalities.