Definition 
Mesenteric venous thrombosis occurs when a blood clot blocks off one of the mesenteric veins, which are the major veins that drain blood from the intestine. This compromises the blood supply to the intestine and can result in intestinal gangrene and tissue death.

Causes, incidence, and risk factors 

There are a variety of causes of mesenteric venous thrombosis. Many of the disease processes that lead to this condition cause inflammation of the tissues through which the mesenteric veins run. Such inflammation damages the mesenteric veins and predisposes them to clot formation (thrombosis).

Pancreatitis, diverticulitis, and (less commonly) appendicitis can all lead to inflammation and mesenteric venous thrombosis. Liver disease with Cirrhosis is also associated with mesenteric venous thrombosis. Patients with hypercoagulable states - in which the blood is more likely to clot - are also at risk for mesenteric venous thrombosis. Such hypercoagulable states can be inherited or associated with cancer or pregnancy.

Symptoms  
In most cases, mesenteric venous thrombosis is a slowly progressive process characterized by chronic Abdominal pain, which is at times worse after eating. Less commonly, acute thrombosis of the mesenteric veins can lead to rapid progression of symptoms with severe, escalating Abdominal pain, sometimes accompanied by Vomiting and diarrhea.

Signs and tests 
CT scan is the diagnostic tool of choice for mesenteric venous thrombosis, and can outline the extent of thrombosis and the degree of vascular compromise to the intestine. Ultrasound of the abdomen and mesenteric veins is also used to determine the presence of clot in the veins.

Treatment  

The mainstay of treatment for mesenteric venous thrombosis is the administration of medication that thins the blood. Heparin is the most commonly used drug. In selected cases, medicine to dissolve the clot can be directly infused into the clot itself (thrombolysis.)

If patients have signs and symptoms of peritonitis, surgery is usually required to remove intestine that has died due to compromise of its blood supply. At times, an ileostomy or colostomy may be necessary.

Expectations (prognosis) 
The prognosis for this condition is quite variable depending on the cause. Prompt therapy prior to the onset of intestinal gangrene, along with treatment of the underlying cause, can result in a good outcome.

Complications 
The most feared complication of mesenteric venous thrombosis is intestinal ischemia, in which some or all of the intestine dies because of poor blood supply from the blocked mesenteric veins.

Calling your health care provider 
Call your health care provider if you are experiencing severe or recurrent Abdominal pains.

Medical Encyclopedia

All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.