What is diverticular bleeding?
Diverticular bleeding occurs when
pouches (diverticula ) that have developed in the wall of the
large intestine (colon) bleed. If you have these pouches, you have a condition
causes a large amount of blood to appear in your stool. Bleeding starts
suddenly and usually stops on its own. Abdominal (belly) pain usually does not occur
with the bleeding.
If you have a large amount of blood in your
stool, see a doctor right away. It is possible, but not common, to quickly lose
so much blood that you become lightheaded or weak.
What causes diverticular bleeding?
The reason pouches
(diverticula) form in the colon wall is not completely understood. Doctors
think diverticula form when high pressure inside the colon pushes against weak
spots in the colon wall.
Normally, a diet with enough fiber
(also called roughage) produces stool that is bulky and can move easily through
the colon. If a diet is low in fiber, the colon must exert more pressure than
usual to move small, hard stool. A low-fiber diet also can increase the time
stool remains in the bowel, adding to the high pressure.
may form when the high pressure pushes against weak spots in the colon. Weak spots are where
blood vessels pass through the muscle layer of the bowel wall to supply blood
to the inner wall.
occurs when the blood vessel going to the pouch breaks open.
What are the symptoms?
usually causes sudden, severe bleeding from the rectum. The blood may be dark
red or bright red clots. In most cases there is no pain, and the bleeding stops
on its own.
How is diverticular bleeding diagnosed?
Diverticular bleeding is diagnosed by ruling out other causes of the
bleeding. Your doctor will do a medical history and physical exam, along
with some tests. Imaging tests such as angiography (also known as
arteriography) may be done to find the location of
Colonoscopy—the inspection of the entire large
intestine (colon) using a long, flexible, lighted viewing scope (colonoscope)—is thought to be one of the most useful tests for finding the source of
bleeding in the lower intestines.
Your doctor might do a test
called a technetium-labeled red blood cell bleeding scan to look for the source
of bleeding. In this test, some blood is taken from you, and a small amount of
radioactive material called technetium is added to the blood. The blood
containing the technetium is then injected back into your bloodstream and
traced to the source of bleeding.