Abernethy syndrome (AS or extrahepatic portosystemic shunt) is an uncommon congenital malformation consisting of agenesis or hypoplasia of the portal vein (PV) in such a way that splanchnic venous blood drains directly into the systemic circulation through aberrant communications, resulting in a portosystemic shunt that bypasses the liver AS is an underdiagnosed condition with unknown incidence and complication rate given that symptoms are usually absent. AS identification is increasingly common because of improved imaging techniques, hence prognostic implications and clinical management need be understood. This editorial reviews the natural history of AS and its diagnostic-therapeutic implications, illustrating the process with a series of cases from our institution.