Congenital extrahepatic portosystemic shunt: description of four cases and review of the literature.

Congenital extrahepatic portosystemic shunt (CEPS), also known as Abernethy malformation, is a rare condition in which the splenomesenteric blood drains directly into a systemic vein, bypassing the liver through a complete or partial shunt. The diagnosis is frequently made during childhood in the setting of neonatal cholestasis, hypergalactosemia, failure to thrive, mental retardation or other congenital defects. In adulthood, CEPS is usually found incidentally during diagnostic work-up for abdominal pain, liver test abnormalities, liver nodules, portopulmonary hypertension, portopulmonary syndrome or portosystemic encephalopathy. The diagnosis depends on imaging and portal venography, but sometimes only liver biopsy can be resolutive, demonstrating the absence of venules within the portal areas. Here we report four recent cases of Abernethy malformation diagnosed in young adults, in which ultrasound (US) was the initial imaging technique and allowed to suspect the diagnosis. Furthermore, we reviewed clinical presentations, associated anomalies and treatment of the 310 cases of CEPS previously reported in the literature.