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Acquired multifactorial condition caused by postsinusoidal
hepatic venous outflow obstruction and
ascites. The cause of the obstruction may be related to hypercoagulability of the
blood, infections, cancer, and other conditions, which may be acute,
chronic, or asymptomatic. The leading cause (in up to 40% of cases),
however, is “idiopathic.”
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Chiari Syndrome; Venoocclusive Disease of the Liver.
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More than 4000 cases have been described.
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No genetic basis has been described. The etiology
is multifactorial; a causative factor is frequently not identified. Risk
factors include myeloproliferative disease, polycythemia rubra vera,
thrombophilia, including factor V Leiden, paroxysmal nocturnal
hemoglobinuria, lupus anticoagulant, protein C deficiency, antithrombin III
deficiency, α1-antitrypsin deficiency, oral contraceptive
medication, pregnancy, malignancy, systemic and local infection, autoimmune
disease, trauma, sarcoidosis, and membranous webs.
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The symptoms result from decreased hepatic venous
outflow, which may be secondary to an obstruction of small hepatic venules
(e.g., following hepatotoxin ingestion), major hepatic veins (caused by
hypercoagulable states, malignancy, or other conditions), or the inferior
vena cava between the hepatic veins and the right atrium (e.g., caused by a
membranous web, thrombosis, progression of renal adenocarcinoma, or
compression from outside). Obstruction to flow results in portal
hypertension and hepatocellular damage. Cirrhosis and portal hypertension
eventually develop. The two-year mortality rate in untreated disease is 20 to
40%.
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The most important diagnostic tool is ultrasonography with
the pathognomonic finding of absent hepatic vein images, intrahepatic collaterals enlargement of the
caudate lobe of the liver, and lack of portal venous, hepatic, and inferior
vena cava blood flow. Alternatively, hepatic venography or MRI may be used.
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Depending on the level of the obstruction, 3 types
of Budd-Chiari syndrome can be distinguished:
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- Type I: occlusion of the inferior vena cava with or without secondary hepatic vein occlusion.
- Type II: occlusion of major hepatic veins.
- Type III: obstruction of small centrilobular venules (also called veno-occlusive disease).
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Very rare in infants and young children. It may
present as either fulminant hepatic failure associated with pain,
hepatomegaly, jaundice, ascites, and rapid deterioration of hepatic function
with encephalopathy requiring acute intervention, or acute nonfulminant
Budd-Chiari syndrome associated with pain, ascites, and hepatomegaly. Chronic
Budd-Chiari syndrome with insidious onset of abdominal discomfort and ascites
because of portal hypertension is also possible. Occlusion of the inferior vena
cava may cause edema of the lower limbs and varicose veins of the legs and
lower trunk. Patients may present with esophageal varices. Management of
Budd-Chiari syndrome may include liver transplantation, particularly in
fulminant forms, formation of cavoatrial or mesoatrial shunts, and use of thrombolytic
agents. Transjugular intrahepatic parto-systemic shunts (TIRS) is becoming popular
to decompress the portal venous system.
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Preoperative investigation should be
aimed at determining the extent of liver and other concomitant organ disease
in addition to the effects of therapy (e.g., diuretics, anticoagulants,
chemotherapy). In severe disease, multisystem involvement is seen. The operative
risk ...