Section 10. Liver and Gallbladder Disorders

Chapter 138. Blood Vessel Disorders of the Liver

Topics: Introduction | Abnormalities of the Hepatic Artery | Veno-occlusive Disease | Budd-Chiari Syndrome | Portal Vein Thrombosis | Blood Vessel Disorders Resulting From Other Diseases

Veno-occlusive Disease

Veno-occlusive disease is a blockage of the small veins in the liver.

Veno-occlusive disease may occur at any age. Children aged 1 to 3 are particularly vulnerable because they have smaller blood vessels, but veno-occlusive disease also occurs in older people. Blockage of the small veins may be caused by substances toxic to the blood vessels in the liver, such as certain alkaloids contained in Crotalaria and Senecio leaves (used in Jamaica to make herbal tea) and certain drugs, including chemotherapy drugs, such as cyclophosphamide and azathioprine. Radiation therapy (such as is used in bone marrow transplantation) also can produce a blockage of the small veins, as can antibodies produced during rejection of a transplanted liver.

Such blockage causes a backup of blood in the liver, reducing the amount of blood flowing into the liver. The insufficient blood supply, in turn, damages the liver cells.

Symptoms

Symptoms of veno-occlusive disease may begin suddenly. Blockage of the small veins causes the liver to swell with blood, making it tender when a doctor presses on the abdomen. Fluid may leak from the surface of the swollen liver and accumulate in the abdomen, producing a condition called ascites. Jaundice (a yellowish discoloration of the skin and the whites of the eyes) may occur. The backup of blood in the liver also raises the pressure in the portal vein (a condition called portal hypertension) and in the veins that empty into it. This higher pressure may cause dilated, twisted (varicose) veins in the esophagus (esophageal varices), which may rupture and bleed, sometimes massively. The bleeding results in vomiting of blood and the passage of blood through the digestive tract, resulting in black stools (melena) and even shock if the bleeding is severe.

Prognosis and Treatment

The prognosis depends on the extent of damage and whether the injury (exposure to a toxin) recurs. Typically, a blockage disappears quickly, and the person recovers regardless of any treatment. However, 25% of people with veno-occlusive disease die of liver failure within about 3 months. In most affected people, the pressure in the portal vein remains high and the injury leads to cirrhosis (severe scarring of the liver).

There is no specific treatment for the blocked veins. In cases caused by the ingestion of a toxic substance, the only treatment is to stop taking that substance. Recurrences are common, particularly if consumption of herbal teas containing Crotalaria or Senecio leaves continues.