Hepatic veno-occlusive disease (VOD) or veno-occlusive disease with immunodeficiency is a potentially life-threatening condition in which some of the small

vein Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenat ...

s in the

liver The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it ...

are obstructed. It is a complication of high-dose

chemotherapy Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs ( chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemothe ...

given before a

bone marrow transplant Hematopoietic stem-cell transplantation (HSCT) is the transplantation of multipotent hematopoietic stem cells, usually derived from bone marrow, peripheral blood, or umbilical cord blood in order to replicate inside of a patient and to produce ...

and/or excessive exposure to hepatotoxic pyrrolizidine alkaloids. It is classically marked by weight gain due to fluid retention, increased liver size, and raised levels of bilirubin in the blood. The name sinusoidal obstruction syndrome (SOS) is preferred if hepatic veno-occlusive disease happens as a result of chemotherapy or bone marrow transplantation. Apart from chemotherapy, hepatic veno-occlusive disease may also occur after ingestion of certain plant alkaloids such as pyrrolizidine alkaloids (in some herbal teas), and has been described as part of a rare

hereditary disease A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders ...

called ''hepatic venoocclusive disease with immunodeficiency'' (which results from mutations in the gene coding for a protein called SP110).

Signs and symptoms

Features of hepatic veno-occlusive disease include weight gain, tender enlargement of the liver,

ascites Ascites is the abnormal build-up of fluid in the abdomen. Technically, it is more than 25 ml of fluid in the peritoneal cavity, although volumes greater than one liter may occur. Symptoms may include increased abdominal size, increased weight, a ...

, and yellow discoloration of the skin; it often is associated with

acute kidney failure Acute kidney injury (AKI), previously called acute renal failure (ARF), is a sudden decrease in kidney function that develops within 7 days, as shown by an increase in serum creatinine or a decrease in urine output, or both. Causes of AKI are c ...

Pathophysiology

In the bone marrow transplant setting, hepatic veno-occlusive disease is felt to be due to injury to the hepatic venous endothelium from the conditioning regimen. Toxic agents causing veno-occlusive disease include plants as well as the medication cyclophosphamide.

Diagnosis

Doppler

ultrasound Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies ...

of the liver is typically utilized to confirm or suggest the diagnosis. Common findings on liver doppler ultrasound include increased phasicity of portal veins with eventual development of portal flow reversal. The liver is usually enlarged but maintained normal

echogenicity Echogenicity (misspelled sometimes as echogenecity) or echogeneity is the ability to bounce an echo, e.g. return the signal in ultrasound examinations. In other words, echogenicity is higher when the surface bouncing the sound echo reflects incre ...

. A

liver biopsy Liver biopsy is the biopsy (removal of a small sample of tissue) from the liver. It is a medical test that is done to aid diagnosis of liver disease, to assess the severity of known liver disease, and to monitor the progress of treatment. Medica ...

is required for a definitive diagnosis.

Treatment

Treatment generally includes supportive care including pain management and possibly

diuretics A diuretic () is any substance that promotes diuresis, the increased production of urine. This includes forced diuresis. A diuretic tablet is sometimes colloquially called a water tablet. There are several categories of diuretics. All diuretics i ...

. In those with severe disease due to a bone marrow transplant, defibrotide is a proposed treatment. It has been approved for use in severe cases in Europe and the United States. A placebo controlled trial, however, has not been done as of 2016.

Prognosis

Mild disease has a risk of death of about 10% while moderate disease has a risk of death of 20%. When it occurs as a result of bone marrow transplant and multiorgan failure is present, the risk of death is greater than 80%.

History

The first report on veno-occlusive disease, in 1920, was as a result of

senecio ''Senecio'' is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels. Variously circumscribed taxonomically, the genus ''Senecio'' is one of the largest genera of flowering plants. Description Mor ...

poisoning in

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

. Subsequent reports were mostly in Jamaicans who had consumed herbal teas. With the advent of bone marrow transplantation, most cases since its introduction have been in those undergoing treatment for

leukemia Leukemia ( also spelled leukaemia and pronounced ) is a group of blood cancers that usually begin in the bone marrow and result in high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or ...

References

External links

{{DEFAULTSORT:Hepatic Veno-Occlusive Disease Hepatology Blood disorders Rare diseases