The long-term prognosis of congenital portosystemic venous shunt.

Congenital portosystemic venous shunt (PSVS), considered to be a rare disease, can lead to hepatic encephalopathy (HE). With improvements in diagnostic imaging techniques, the number of infants and children with documented PSVS has increased. The natural course of the disease and indications for surgical closure of the shunt vessel have not been well defined. We reviewed 51 cases of congenital PSVS in Japan; 34 patients had an intrahepatic PSVS, and 17 had an extrahepatic PSVS. There were 12 patients with HE at the time of diagnosis. The frequency of HE increased in subjects over 60 years of age. Children with HE had a shunt ratio exceeding 60%. When the shunt ratio was less than 30%, HE did not occur. Twenty of 28 patients under the age of 15 years had hypergalactosemia at the time of neonatal screening. Part of the congenital intrahepatic PSVS spontaneously closed. Surgical closure of a PSVS may be an approach expected to prevent HE when the shunt ratio exceeds 60%.