Angiodysplasia of the colon is swollen, fragile blood vessels in the colon. This can result in blood loss from the gastrointestinal (GI) tract.
Vascular ectasia of the colon; Colonic arteriovenous malformation
Angiodysplasia of the colon is mostly related to the aging and degeneration of the blood vessels. It is more common in older adults. It is almost always seen on the right side of the colon.
Most likely, the problem develops out of normal spasms of the colon that lead to the enlargement of blood vessels in the area. When this swelling becomes severe, a tiny passageway develops between a small artery and vein. This is called an arteriovenous malformation. It is in this area of the colon wall that the patient is at risk for bleeding.
Rarely, angiodysplasia of the colon is related to other diseases of the blood vessels, including Osler-Weber-Rendu syndrome. It is not related to cancer. It is also different than diverticulosis, which is a more common cause of intestinal bleeding in older adults.
The symptoms vary.
Many times, older people have symptoms of weakness, fatigue and shortness of breath due to anemia. They may not have bleeding directly from the colon. Others may have bouts of mild or severe bleeding in which bright red blood comes from the rectum.
There is no pain associated with angiodysplasia.
Exams and Tests
Tests that may be done to diagnose this condition include:
Angiography (only useful if there is active bleeding into the colon)
Complete blood count (CBC) to check for anemia
Stool test for occult (hidden) blood (a positive test result suggests bleeding from the colon)
It is important to determine what is causing the bleeding in the colon and how fast blood is being lost. You may need to be admitted to a hospital. Fluids may be given through a vein, and blood products may be required.
Other treatment may be needed once the source of bleeding is found. Most patients stop bleeding on their own without any treatment.
If treatment is needed, it may involve:
Angiography to help block the blood vessel that is bleeding or to deliver medicine to help cause the blood vessels to tighten to stop the bleeding
Burning (cauterizing) the site of the bleed with heat or a laser using a colonoscope
In some instances, surgery is the only option. Removal of the entire right side of the colon (right hemicolectomy) may be done if heavy bleeding continues even after other treatments have been tried. Medicines (thalidomide and estrogens) may be used to help control the disease in some people.
Patients who have bleeding related to this condition despite having had colonoscopy, angiography, or surgery are likely to have more bleeding in the future.
The outlook remains good if the bleeding is controlled.
Call your health provider if rectal bleeding occurs.
There is no known prevention.
Hauser S. Vascular diseases of the gastrointestinal tract. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 145.
Brandt LJ, Landis CS. Vascular lesions of the gastrointestinal tract. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2010:chap 36.
George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.