Asymptomatic presentation of a congenital malformation of the portal vein with portosystemic shunt.

Malformations of the portal venous system consist of congenital and acquired anomalies. Congenital portosystemic shunts represent rare vascular developmental anomalies that allow partial or complete diversion of blood flow from the portal venous system to the systemic venous system, bypassing the liver. Congenital portosystemic shunts may be associated with malformations or congenital absence of the portal vein, and it was first described by John Abernethy in 1793. Most cases are diagnosed in early childhood, but some congenital shunts may remain asymptomatic and are encountered incidentally because of the widespread use of computed tomography and magnetic resonance imaging. In this report, we discuss the case of a 40-year-old female who presented to the Emergency Department with right upper quadrant pain, nausea, and vomiting. Clinical presentation and abdominal computed tomography angiography were consistent with the diagnosis of calculous cholecystitis and congenital absence of portal vein with intrahepatic portosystemic shunts. We discuss the importance of radiology in diagnosing such incidental malformations, coupled with a review of the current literature on this topic.