Diverticulosis - Topic Overview
What is diverticulosis?
Diverticulosis is a condition that
develops when pouches (diverticula ) form in the wall of the colon (large intestine ). These pouches are usually very small (5 to 10 millimeters) in diameter but can be larger.
In diverticulosis, the pouches in the colon wall do not
cause symptoms. Diverticulosis may not be discovered unless symptoms occur,
such as in painful diverticular disease or in
diverticulitis. As many as 80 out of 100 people who have
diverticulosis never get diverticulitis.1 In many
cases, diverticulosis is discovered only when tests are done to find the cause
of a different medical problem or during a screening exam.
What causes diverticulosis?
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 adequate 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 where
blood vessels pass through the muscle layer of the bowel wall to supply blood
to the inner wall.
What are the symptoms?
Most people don't have
symptoms. You may have had diverticulosis for years
by the time symptoms occur (if they do). Over time, some people get an
infection in the pouches (diverticulitis). For more information, see the topic
Your doctor may use the term painful diverticular disease. It's likely that painful diverticular disease is caused by irritable bowel syndrome
(IBS). Symptoms include diarrhea and cramping abdominal (belly) pain, with no fever or other
sign of an infection. For information on the symptoms of IBS, see the topic
Irritable Bowel Syndrome (IBS).
How is diverticulosis diagnosed?
In many cases,
diverticulosis is discovered only when tests, such as a
barium enema X-ray or a
colonoscopy, are done to find the cause of a different
medical problem or during a screening exam.