Angiodysplasia of the Colon
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Angiodysplasia of the Colon

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

En Español (Spanish Version)


Angiodysplasia of the colon occurs when enlarged and fragile blood vessels in the colon result in occasional bleeding in the gastrointestinal (GI) tract. If you think you may have this condition, contact your doctor immediately.

Normal Anatomy of the Intestines

Normal Anatomy of the Large and Small Intestine

© 2008 Nucleus Medical Art, Inc.


Angiodysplasia of the colon can be caused by:

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. The following risk factors increase your chance of having angiodysplasia of the colon. If you have any of these risk factors, tell your doctor:

  • Age: older than 60 years


People with angiodysplasia of the colon may or may not have symptoms. If you experience any of these symptoms do not assume it is due to angiodysplasia of the colon. These symptoms may be caused by other health conditions. If you experience any one of them, see your physician.

  • Bleeding from the rectum
  • Anemia
  • Weakness
  • Fatigue
  • Shortness of breath
  • Dark, tarry stools


Your doctor will ask about your symptoms and medical history, and perform a physical exam. Tests may include the following:

  • Colonoscopy—a thin, lighted tube inserted through the rectum and into the colon to examine the lining of the colon
  • Upper endoscopy (EGD)—a thin, lighted tube inserted through the mouth and into the esophagus, stomach, and small intestine
  • Radiology testing with CT scan, nuclear medicine imaging (tagged red cell scanning), or other techniques
  • Angiography—a test that involves injecting dye into the veins to view on an x-ray
  • Complete blood count (CBC)—a test to measure the amount of red blood cells
  • Stool guaiac—a test to look for blood in the stool


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 cauterize (burn tissues with thermal heat to seal bleeding blood vessels) the site of the bleeding 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.


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


There is no known way 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


Angiodysplasia. DynaMed website. Available at: Accessed November 29, 2006.

American Gastroenterological Association. AGA guideline: evaluation and management of occult and obscure gastrointestinal bleeding. Gastroenterology . 2000;118:197.

American Gastroenterological Association website. Available at:

Disorders of the digestive system. The AGS Foundation for Health in Aging website. Available at: Accessed November 27, 2006.

Last reviewed February 2008 by Daus Mahnke, MD

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.

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