Impact of Portal Flow on the Prognosis of Children With Congenital Portosystemic Shunt: A Multicentric Observation Study in Japan

Background: Although congenital portosystemic shunts (CPSSs) are increasingly being recognized, the optimal treatment strategies and natural prognosis remain unclear, as individual CPSSs show different phenotypes. Methods: The medical records of 122 patients who were diagnosed with CPSSs at 15 participating hospitals in Japan between 2000 and 2019 were collected for a retrospective analysis based on the state of portal vein (PV) visualization on imaging. Results: Among the 122 patients, 75 (61.5%) showed PV on imaging. The median age at the diagnosis was 5 months. The main complications related to CPSS were hyperammonemia (85.2%), liver masses (25.4%), hepatopulmonary shunts (13.9%), and pulmonary hypertension (11.5%). The prevalence of complications was significantly higher in patients without PV visualization than in those with PV visualization (P < 0.001). Overall, 91 patients (74.6%) received treatment, including shunt closure by surgery or interventional radiology (n = 82) and liver transplantation (LT) or liver resection (n = 9). Over the past 20 years, there has been a decrease in the number of patients undergoing LT. Although most patients showed improvement or reduced progression of symptoms, liver masses and pulmonary hypertension were less likely to improve after shunt closure. Complications related to shunt closure were more likely to occur in patients without PV visualization (P = 0.001). In 25 patients (20.5%) without treatment, those without PV visualization were significantly more likely to develop complications related to CPSS than those with PV visualization (P = 0.011). Conclusion: Patients without PV visualization develop CPSS-related complications and, early treatment using prophylactic approaches should be considered, even if they are asymptomatic. Level of Evidence: Level III.