Veno-Occlusive Disease (VOD)

Veno-occlusive disease (VOD), also known as hepatic veno-occlusive disease and hepatic sinusoidal obstruction syndrome (SOS), is a condition wherein some of the small blood vessels in and around the liver become blocked. Veno-occlusive disease typically occurs after stem cell transplantation, due to the effects of chemotherapy and radiation therapy. Though complications can range from mild to life-threatening, in most cases with early detection and treatment, the liver can repair itself.

Signs and symptoms typically show within the first month post-transplant, and may include one or more of the following:

  • Ascites
  • Drowsiness
  • Jaundice
  • Liver enlargement
  • Mental confusion
  • Sudden weight gain
  • Swelling in the legs

The exact underlying cause or causes of VOD are unknown, however (nontransplant‒related) risk factors may include age, genetic or acquired iron overload, the ingestion of certain herbal remedies, previous high-dose radiation therapy to the liver or abdomen, and pre-existing liver disease.

Treatment options for VOD may include one or more of the following:

  • Defibrotide is the only agent approved by the US Food and Drug Administration for the treatment of VOD
  • Supportive care