A 34-year-old woman on oral contraceptives develops abdominal distension and dull right upper quadrant pain over 3 weeks. Examination shows tense ascites and smooth hepatomegaly. Ascitic fluid protein is 3.5 g/dL. Doppler ultrasound shows absent flow in the right and middle hepatic veins with a hypertrophied caudate lobe. If a thrombophilic cause is sought, the most commonly identified association worldwide is:

• A Antiphospholipid antibody syndrome
• B JAK2 V617F positive myeloproliferative neoplasm ✓
• C Paroxysmal nocturnal hemoglobinuria
• D Behcet disease

Explanation

Budd-Chiari syndrome results from thrombosis of hepatic veins or the suprahepatic inferior vena cava. Myeloproliferative neoplasms, especially polycythemia vera and essential thrombocythemia carrying JAK2 V617F, are the most frequently identified underlying cause worldwide, even when blood counts appear normal. Preserved caudate lobe drainage through direct caval veins explains caudate hypertrophy. Antiphospholipid syndrome and paroxysmal nocturnal hemoglobinuria are recognized but far less common associations.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.