Budd-Chiari syndrome (BCS) is a very rare disease in which there is a complete or partial blockage of the outflow of blood from the liver. The outflow obstruction can affect the small hepatic veins, classically the large hepatic veins or the vena cava inferior between the hepatic veins and the right atrium of the heart. The backflow of blood into the liver can lead to increased pressure in the portal vein and/or the death of liver tissue. The clinical picture ranges from asymptomatic to acute liver failure or cirrhosis.

Causes of BCS

The most common cause of primary BCS in the Western world is blood clots in the hepatic veins and the neighbouring vena cava inferior. While the underlying causes are unclear in most cases, a number of conditions that increase the risk of thrombosis are considered risk factors.

They include primary myeloproliferative neoplasms that have a genetic cause, genetic coagulation defects such as factor 5 Leiden mutation, protein C deficiency, antiphospholipid syndrome, Behçet's disease, paroxysmal nocturnal haemoglobinuria (PNH), contraceptive use and systemic inflammatory diseases. Occasionally, BCS occurs during pregnancy.

In secondary BCS, the blood flow from the liver is blocked for other reasons, such as malignant tumours, liver cysts, liver adenomas, parasites, or other infections.

Symptoms

The highly variable symptoms range from almost no or minor non-specific symptoms such as nausea, tiredness and pain to symptoms that are more specific to liver disease such as jaundice, ascites, or bleeding from varicose veins in the oesophagus or stomach. However, the acute reflux of blood into the liver can also lead to acute liver failure and, if it progresses chronically, to cirrhosis. Both phenomena are life-threatening.

Diagnosis

Often no invasive examination is necessary to diagnose BCS. The diagnosis of BCS can be made with a Doppler sonography or with an MRI or CT scan. The underlying disease for the BCS should also be identified.

Treatment

The treatment of BCS is complex and should be carried out by experienced specialists in a specialised liver centre. Primary BCS is treated with anticoagulants or even thrombus-dissolving drugs, unless there are serious contraindications. In more severe or advanced cases, additional measures are required.

It is possible to make the blocked veins partially permeable again using radiological interventions. The use of a TIPS (transjugular intrahepatic portosystemic shunt) is another option for restoring blood flow. Complications such as bleeding from the oesophagus or from the stomach and ascites must also be treated. If other methods are not effective, a liver transplant is often the last resort. It is also important to treat pre-existing conditions.