A 10-year-old boy with dyspnea and hypoxia: abernathy malformation masquerading as pulmonary arteriovenous fistula

Abernethy malformation is an extremely rare congenital malformation characterised by an extrahepatic portosystemic shunt. Children with Abernathy malformation can develop hepatopulmonary syndrome (HPS) with pulmonary arteriovenous fistulas (PAVF) or pulmonary hypertension. PAVF manifests as central cyanosis with effort intolerance. We report a case of PAVF in a Ten-year-old Boy. Persistent symptoms identified Abernathy malformation as the cause of progressive symptoms and current understanding of this rare malformation is reviewed.

A case of 10-year-old boy with Abernethy malformation complicated with HPS initially managed as PAVF was presented. Selective lung angiography showed a typical diffuse reticular pattern on right lower lung, which suggested PAVF. However, cyanosis was not improved post transcatheter coil embolization. Then, liver disease was considered although the patient had normal aspartate aminotransferase and alanine aminotransferase. The significantly elevated serum ammonia was attracted our attention. Abdominal computed tomography also exhibited enlarged main portal vein (MPV), cirsoid spleen vein, and superior mesenteric vein (SMV). Angiography with direct opacification of the SMV with a catheter coming from the inferior vena cava (IVC) and going to the SMV via the shunt vessel (SHUNT) between the MPV and IVC. Occlusion the IVC with an inflated balloon, injection of contrast medium via a catheter placed in the SMV, MPV was showed and absence of intrahepatic branches. Abernethy malformation IB type is finally confirmed.

Abernethy malformation is an unusual cause for development of PAVF and cyanosis in children. Clinicians must be suspicious of Abernethy malformation complicated with HPS. If patients have abnormal serum ammonia and enlarged MPV in abdominal CT, cathether angiography should be done to rule out Abernethy malformation.