Incidence and risk factors for portal vein complications after pediatric liver transplantation: A retrospective cohort analysis from the PORTAL registry

Portal vein complications (PVCs) are recognized but infrequent complications following pediatric liver transplantation (pLT), particularly in young patients with biliary atresia (BA). However, the exact incidence of PVCs remains unclear. This study aimed to determine the overall incidence of PVCs after pLT and to explore variations within specific subgroups defined by indication for pLT, age at pLT, donor type, transplant era, and center volume. Differences between portal vein stenosis (PVS) and portal vein occlusion (PVO) were also examined. The Portal Vein Obstruction Revascularization Therapy After Liver Transplantation (PORTAL) registry, a multicenter, retrospective, observational database, collected data on PVCs from 21 pLT centers. Analysis of 6035 pLT procedures performed over a 19-year period identified 385 cases of PVCs, yielding an overall incidence of 6.3%. PVS and PVO most commonly occurred within the first year post-pLT, with PVO peaking in the first week and PVS cases distributed more evenly throughout the year. The incidence was highest following pLT for BA performed before the age of 1 year (13.0%). PVC rates increased over time, rising from 4.3% during 2001–2006 to 6.9% during 2016–2020. The highest rates of PVS and the lowest rates of PVO were observed in high-volume centers. These findings clarify the incidence of PVCs among pLT recipients and provide critical insights to improve prevention, early detection, and management strategies for these complications.