Malformation of Abernethy type 2: presentation of a clinical case and review of literature

Abdominal venous system malformations are rare vascular alterations that occur during the embryonic period after the formation of new venous systems. They are generally associated with other malformations, among which are mainly portocava anastomosis and venous duct agenesis with asymmetric cardiac development and intestinal rotation. These anomalies have been described occasionally associated with chromosomal alterations such as trisomy 21.1 The first described case of an Extrahepatic Congenital Portosystemic Shunt (SPCE) was in the year of 1793 by John Abernethy. In 1883, Kiernan described the second case of congenital porto cava anastomosis in an 18-year-old adolescent in whom the hepatic artery was elongated.2 This malformation is classified into two variants according to its anastomosis with the portal vein and its anastomosis with the inferior vena cava (IVC). In type I there is a complete deviation of portal blood to the IVC and the extrahepatic portal vein is absent; while in type II there is a partial portal flow to the liver through a hypoplastic portal vein (VP).Since its discovery 80 cases have been described until 2014 worldwide, the majority of patients under 18 years. Type I malformation occurred in 74% of the reported cases, is present in childhood and is associated with other malformations. Until 2013, 32 cases of type I were reported worldwide.