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

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.