Colonic angiomas

Alternative names

Vascular ectasia of the colon; Colonic arteriovenous malformation; Angiodysplasia of the colon

Definition

Angiodysplasia of the colon is a condition of dilated and fragile blood vessels in the colon that results in intermittent loss of blood from the gastrointestinal tract. The condition is mostly related to the aging and degeneration of the blood vessels, as it occurs in older adults.

Angiodysplasia of the colon is not related to cancers or other congenital disease of the blood vessels. It is different than diverticulosis, another very common cause of bleeding in older adults.

Causes, incidence, and risk factors

There are several theories about the cause of angiodysplasia of the colon. The most likely is that normal contractions of the colon result in dilation (stretching) of colonic veins, venules, and capillaries. The dilation becomes so severe that a small direct passageway develops between the artery and vein (arteriovenous fistula). It is in this area of the colon wall that the patient is at risk for bleeding.

Angiodysplasia of the colon has been seen in about 3% of "nonbleeding persons" and in about 5% of patients evaluated for blood in the stool, anemia, or hemorrhage. Men and women are equally at risk for developing angiodysplasia of the colon. Most patients are older than 50 years.

Symptoms

The symptoms can vary. Often in elderly patients, the symptoms are anemia, weakness, fatigue, and shortness of breath. There may not be any signs of bleeding directly from the colon. Others may have intermittent mild or severe bleeding episodes with bright red blood coming from the rectum.

Some patients may have dark or black, tarry stools. There is no pain associated with angiodysplasia.

Signs and tests

Colonoscopy - Examining the walls of the colon using a camera on the end of a long tube inserted into the rectum.

Angiography - Injecting dye into the veins to visualize any leakage of the dye from the arteries/veins into the colon. This is visualized with x-rays. This test is only useful if there is active bleeding into the colon.

CBC - A blood test that measures the amount of red blood cells in your system. A low amount suggests bleeding from the colon.

Stool guaiac - A test to look for blood in the stool that cannot be seen by the naked eye. Small amounts of stool are placed on 3 cards and analyzed at the doctor's office. The samples are checked for any evidence of blood. A positive test result suggests bleeding from the colon.

Treatment