Budd-Chiari syndrome (BCS) is a relatively rare disease, most commonly found in middle-aged females, and is caused by hepatic vein blockage, except in Asian countries where it is more commonly found in males with inferior vena cava (IVC) obstruction.[1] The condition is classified as either primary or secondary depending on the source of the obstruction and whether it originates from within the venous system, such as in thrombosis, or external to the venous system, such as in compression by tumors of adjacent organs or polycystic kidney disease. Primary BCS is the most common manifestation and is most prevalent in those with underlying thrombogenic disorders such as primary myeloproliferative disease, essential thrombocythemia, and myelofibrosis.[2] Conditions that result in hypercoagulability such as pregnancy, oral contraceptive use, factor V mutation, antithrombin deficiency, protein C deficiency, and paroxysmal nocturnal hemoglobinuria can also cause primary BCS.[3] However, in most cases, the local cause of the thrombus formation cannot be identified.

BCS generally becomes clinically evident after the occlusion of two or more major hepatic veins ([Figs. 1] and [2]). This causes a build-up of sinusoidal pressure and increased filtration of interstitial fluid into the liver capsule after the capacity of lymphatic drainage capacity has been exceeded. Resulting portal hypertension causes reduced hepatic blood flow and hepatocyte damage.[2] BCS and its progression can range in severity from asymptomatic, unobtrusive disease to acute, debilitating disease with significant morbidity.[4] [5] When symptomatic, BCS can present with abdominal pain and/or distention, ascites, hepatomegaly, jaundice, upper gastrointestinal bleeding, hepatic encephalopathy, and edema.[4] In chronic cases, patients can also present with renal impairment.[1]