Primary Budd–Chiari syndrome (75%): thrombosis of the hepatic vein
Hepatic vein thrombosis is associated with the following in decreasing order of frequency:Polycythemia vera
Pregnancy
Postpartum state
Use of oral contraceptives
Paroxysmal nocturnal hemoglobinuria
Hepatocellular carcinoma
Lupus anticoagulantsSecondary Budd–Chiari syndrome (25%): compression of the hepatic vein by an outside structure (e.g. a tumor)Budd–Chiari syndrome is also seen in tuberculosis, congenital venous webs and occasionally in inferior vena caval stenosis. Often, the patient is known to have a tendency towards thrombosis, although Budd–Chiari syndrome can also be the first symptom of such a tendency. Examples of genetic tendencies include protein C deficiency, protein S deficiency, the Factor V Leiden mutation, hereditary anti-thrombin deficiency and prothrombin mutation G20210A. An important non-genetic risk factor is the use of estrogen-containing (combined) forms of hormonal contraception. Other risk factors include the antiphospholipid syndrome, aspergillosis, Behçets disease, dacarbazine, pregnancy, and trauma.Many patients have Budd–Chiari syndrome as a complication of polycythemia vera (myeloproliferative disease of red blood cells). People who have paroxysmal nocturnal hemoglobinuria (PNH) appear to be especially at risk for Budd–Chiari syndrome, more than other forms of thrombophilia: up to 39% develop venous thromboses, and 12% may acquire Budd-Chiari.A related condition is veno-occlusive disease, which occurs in recipients of bone marrow transplants as a complication of their medication. Although its mechanism is similar, it is not considered a form of Budd–Chiari syndrome.Other toxicologic causes of veno-occlusive disease include plant & herbal sources of pyrrolizidine alkaloids such as Borage, Boneset, Coltsfoot, Tu-san-chi, Comfrey, Heliotrope (sunflower seeds), Gordolobo, Germander, and Chaparral.
Budd–Chiari syndrome is a very rare condition, affecting one in a million adults. The condition is caused by occlusion of the hepatic veins that drain the liver. It presents with the classical triad of abdominal pain, ascites, and liver enlargement. The formation of a blood clot within the hepatic veins can lead to Budd–Chiari syndrome. The syndrome can be fulminant, acute, chronic, or asymptomatic. Subacute presentation is the most common form. Signs and symptoms
The acute syndrome presents with rapidly progressive severe upper abdominal pain, yellow discoloration of the skin and whites of the eyes, liver enlargement, enlargement of the spleen, fluid accumulation within the peritoneal cavity, elevated liver enzymes, and eventually encephalopathy. The fulminant syndrome presents early with encephalopathy and ascites. Liver cell death and severe lactic acidosis may be present as well. Caudate lobe enlargement is often present. The majority of patients have a slower-onset form of Budd–Chiari syndrome. This can be painless. A system of venous collaterals may form around the occlusion which may be seen on imaging as a "spiders web". Patients may progress to cirrhosis and show the signs of liver failure.On the other hand, incidental finding of a silent, asymptomatic form may not be a cause for concern. Causes
The cause can be found in more than 80% of patients.