Congenital extrahepatic portosystemic shunts (Abernethy malformation): A report of two cases

Abernethy malformation, also known as congenital extrahepatic portosystemic shunt, is an extremely rare vascular anomaly that alters systemic hemodynamics and may lead to progressive liver dysfunction, portal hypertension, and, in advanced stages, malignant transformation or hepatic encephalopathy. The condition is frequently associated with other congenital anomalies, most notably cardiac malformations such as septal defects, patent foramen ovale, Tetralogy of Fallot, and valvular regurgitation as well as skeletal abnormalities. We report the cases of two patients-one with type Ib and the other with type II Abernethy malformation. Both patients were asymptomatic, with the diagnosis established through contrast-enhanced computed tomography and magnetic resonance imaging. Clinical, laboratory, and imaging data were collected. Given the absence of overt clinical manifestations, both patients are being managed with semiannual follow-up. Abernethy malformation is difficult to diagnose based on clinical presentation alone; however, characteristic imaging features can facilitate a definitive diagnosis. Recognition of this rare entity and its potential comorbidities is essential for timely diagnosis and appropriate management.