A 34-year-old woman taking combined oral contraceptives presents with 10 days of dull right upper quadrant pain, abdominal distension, and tender hepatomegaly. Ascitic fluid has a protein content of 3.2 g/dL. Doppler ultrasound shows absent flow in all three hepatic veins with a caudate lobe hypertrophied and brightly enhancing. Which single test is most likely to identify the underlying cause in a Western population?

• A Alpha-fetoprotein level
• B Anticardiolipin antibody titre
• C Serum homocysteine level
• D JAK2 V617F mutation testing ✓

Explanation

The picture is Budd-Chiari syndrome: hepatic vein outflow obstruction causing painful hepatomegaly, ascites rich in protein, and characteristic caudate lobe hypertrophy because its venous drainage bypasses the obstructed hepatic veins. The commonest underlying disorder in Western series is an occult myeloproliferative neoplasm, detected by the JAK2 V617F mutation even when counts are normal. Oral contraceptives act as cofactors, not as sufficient causes, so they do not end the search.

Reference: Sherlock's Diseases of the Liver and Biliary System, 13th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.