For more information, call: 573-331-3000

A-Z Health Topics

Return to Index
by McCoy K

Angiodysplasia of the Colon

(Colonic Angiodysplasia, Arteriovenous Malformations [AVM] of the Colon)


Angiodysplasia of the colon occurs when blood vessels in the colon enlarge. They may become fragile and result in occasional bleeding in the gastrointestinal (GI) tract.
Normal Anatomy of the Intestines
Normal Anatomy of the Large and Small Intestine
Copyright © Nucleus Medical Media, Inc.


Angiodysplasia of the colon is caused by dilated connections between veins and capillaries or arteries in the large intestine (colon).

Risk Factors

Factors that may increase your risk of angiodysplasia of the colon include:
  • Increasing age
  • Excessive or abnormal contractions of the colon
  • Injury to the GI tract
  • Heart problems
  • Kidney problems
  • Lung problems
  • von Willebrand's disease—a disorder of the blood
  • Blood vessel problems


Symptoms of angiodysplasia of the colon may include:
  • Dark, tarry stools
  • Bleeding from the rectum
  • Anemia
  • Weakness
  • Fatigue
  • Shortness of breath


Your doctor will ask about your symptoms and medical history. A physical exam will be done.
Your bodily fluids and waste may be tested. This can be done with:
  • Blood tests
  • Stool tests
Your internal structures may need to be viewed. This can be done with:


Talk with your doctor about the best treatment plan for you. Treatment may not be necessary, since about 90% of cases of angiodysplasia of the colon stop bleeding on their own. Treatment options include the following:


Your doctor can often treat tissues with heat to seal bleeding blood vessels during a colonoscopy.


The blood supply to the bleeding area can be clotted through angiography.

Medical Therapy

Hormonal therapy with estrogen can be helpful for some causes.
Medications called somatostatin analogs may be used to prevent bleeding in some people.


Surgery to remove the affected area of the colon may sometimes be necessary.


There are no current guidelines to prevent angiodysplasia of the colon.


AGS Foundation for Health in Aging
National Digestive Diseases Information Clearinghouse


Canadian Association of Gastroenterology
Canadian Digestive Health Foundation


American Gastroenterological Association. AGA guideline: Evaluation and management of occult and obscure gastrointestinal bleeding. Gastroenterology. 2000;118:197.
Gastrointestinal angiodysplasia. EBSCO DynaMed website. Available at: Updated June 2, 2014. Accessed June 16, 2014.
6/19/2014 DynaMed's Systematic Literature Surveillance Jackson CS, Gerson LB. Management of gastrointestinal angiodysplastic lesions (GIADs): A systematic review and meta-analysis. Am J Gastroenterol. 2014;109(4):474-483.

Revision Information