A 31-year-old woman on combined oral contraceptives presents with sudden right upper quadrant pain, tender hepatomegaly, and ascites. Doppler ultrasound shows absent flow in all three hepatic veins with an intrahepatic collateral vessel resembling a spider web. Which etiological test is most appropriate first?
- A JAK2 V617F mutation testing ✓
- B Antiphospholipid antibody panel
- C Serum homocysteine level
- D Factor V Leiden testing
Correct answer: A. JAK2 V617F mutation testing
Explanation
Budd-Chiari syndrome from hepatic vein thrombosis is caused most often by an underlying myeloproliferative neoplasm, frequently subclinical polycythemia vera or essential thrombocythemia. The JAK2 V617F mutation is present in the large majority of such cases and is recommended as a first-line screen because it can be detected even before blood counts become abnormal. Estrogen exposure acts as the precipitating prothrombotic trigger rather than the root cause.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.