Diverticulosis and Diverticulitis
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Many people have small pouches in their colons that bulge outward
through weak spots, like an inner tube that pokes through weak places in a
tire. Each pouch is called a diverticulum. Pouches (plural) are called
diverticula. The condition of having diverticula is called diverticulosis.
About 10 percent of Americans over the age of 40 have diverticulosis. The
condition becomes more common as people age. About half of all people over
the age of 60 have diverticulosis.
When the pouches become infected or inflamed, the condition is called
diverticulitis. This happens in 10 to 25 percent of people with
diverticulosis. Diverticulosis and diverticulitis are also called
Although not proven, the dominant theory is that a low-fiber diet is
the main cause of diverticular disease. The disease was first noticed in
the United States in the early 1900s. At about the same time, processed
foods were introduced into the American diet. Many processed foods contain
refined, low-fiber flour. Unlike whole-wheat flour, refined flour has no
Diverticular disease is common in developed or industrialized
countries--particularly the United States, England, and Australia--where
low-fiber diets are common. The disease is rare in countries of Asia and
Africa, where people eat high-fiber vegetable diets.
Fiber is the part of fruits, vegetables, and grains that the body
cannot digest. Some fiber dissolves easily in water (soluble fiber). It
takes on a soft, jelly-like texture in the intestines. Some fiber passes
almost unchanged through the intestines (insoluble fiber). Both kinds of
fiber help make stools soft and easy to pass. Fiber also prevents
Constipation makes the muscles strain to move stool that is too hard.
It is the main cause of increased pressure in the colon. This excess
pressure might cause the weak spots in the colon to bulge out and become
Diverticulitis occurs when diverticula become infected or inflamed.
Doctors are not certain what causes the infection. It may begin when stool
or bacteria are caught in the diverticula. An attack of diverticulitis can
develop suddenly and without warning.
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Most people with diverticulosis do not have any discomfort or symptoms.
However, symptoms may include mild cramps, bloating, and constipation.
Other diseases such as irritable bowel syndrome (IBS) and stomach ulcers
cause similar problems, so these symptoms do not always mean a person has
diverticulosis. You should visit your doctor if you have these troubling
The most common symptom of diverticulitis is abdominal pain. The most
common sign is tenderness around the left side of the lower abdomen. If
infection is the cause, fever, nausea, vomiting, chills, cramping, and
constipation may occur as well. The severity of symptoms depends on the
extent of the infection and complications.
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Diverticulitis can lead to bleeding, infections, perforations or tears,
or blockages. These complications always require treatment to prevent them
from progressing and causing serious illness.
Bleeding from diverticula is a rare complication. When diverticula
bleed, blood may appear in the toilet or in your stool. Bleeding can be
severe, but it may stop by itself and not require treatment. Doctors
believe bleeding diverticula are caused by a small blood vessel in a
diverticulum that weakens and finally bursts. If you have bleeding from
the rectum, you should see your doctor. If the bleeding does not stop,
surgery may be necessary.
The infection causing diverticulitis often clears up after a few days
of treatment with antibiotics. If the condition gets worse, an abscess may
form in the colon.
An abscess is an infected area with pus that may cause swelling and
destroy tissue. Sometimes the infected diverticula may develop small
holes, called perforations. These perforations allow pus to leak out of
the colon into the abdominal area. If the abscess is small and remains in
the colon, it may clear up after treatment with antibiotics. If the
abscess does not clear up with antibiotics, the doctor may need to drain
To drain the abscess, the doctor uses a needle and a small tube called
a catheter. The doctor inserts the needle through the skin and drains the
fluid through the catheter. This procedure is called percutaneous catheter
drainage. Sometimes surgery is needed to clean the abscess and, if
necessary, remove part of the colon.
A large abscess can become a serious problem if the infection leaks out
and contaminates areas outside the colon. Infection that spreads into the
abdominal cavity is called peritonitis. Peritonitis requires immediate
surgery to clean the abdominal cavity and remove the damaged part of the
colon. Without surgery, peritonitis can be fatal.
A fistula is an abnormal connection of tissue between two organs or
between an organ and the skin. When damaged tissues come into contact with
each other during infection, they sometimes stick together. If they heal
that way, a fistula forms. When diverticulitis-related infection spreads
outside the colon, the colon's tissue may stick to nearby tissues. The
organs usually involved are the bladder, small intestine, and skin.
The most common type of fistula occurs between the bladder and the
colon. It affects men more than women. This type of fistula can result in
a severe, long-lasting infection of the urinary tract. The problem can be
corrected with surgery to remove the fistula and the affected part of the
The scarring caused by infection may cause partial or total blockage of
the large intestine. When this happens, the colon is unable to move bowel
contents normally. When the obstruction totally blocks the intestine,
emergency surgery is necessary. Partial blockage is not an emergency, so
the surgery to correct it can be planned.
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To diagnose diverticular disease, the doctor asks about medical
history, does a physical exam, and may perform one or more diagnostic
tests. Because most people do not have symptoms, diverticulosis is often
found through tests ordered for another ailment.
The doctor will ask about medical history.
When taking a medical history, the doctor may ask about bowel habits,
symptoms, pain, diet, and medications. The physical exam usually involves
a digital rectal exam. To perform this test, the doctor inserts a gloved,
lubricated finger into the rectum to detect tenderness, blockage, or
blood. The doctor may check stool for signs of bleeding and test blood for
signs of infection. The doctor may also order x rays or other tests.
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A high-fiber diet and, occasionally, mild pain medications will help
relieve symptoms in most cases. Sometimes an attack of diverticulitis is
serious enough to require a hospital stay and possibly surgery.
Increasing the amount of fiber in the diet may reduce symptoms of
diverticulosis and prevent complications such as diverticulitis. Fiber
keeps stool soft and lowers pressure inside the colon so that bowel
contents can move through easily. The American Dietetic Association
recommends 20 to 35 grams of fiber each day. The table below shows the
amount of fiber in some foods that you can easily add to your diet.
|Apple, raw, with skin
|Asparagus, fresh, cooked
|Broccoli, fresh, cooked
|Brussels sprouts, fresh, cooked
|Cabbage, fresh, cooked
|Carrot, fresh, cooked
|Cauliflower, fresh, cooked
|Spinach, fresh, cooked
|Summer squash, cooked
|Winter squash, cooked
|Baked beans, canned, plain
|Kidney beans, fresh, cooked
|Lima beans, fresh, cooked
|Potato, fresh, cooked
|Brown rice, cooked
|Cereal, bran flake
|Oatmeal, plain, cooked
|White rice, cooked
The doctor may also recommend taking a fiber product such as Citrucel
or Metamucil once a day. These products are mixed with water and provide
about 2 to 3.5 grams of fiber per tablespoon, mixed with 8 ounces of
Until recently, many doctors suggested avoiding foods with small seeds
such as tomatoes or strawberries because they believed that particles
could lodge in the diverticula and cause inflammation. However, it is now
generally accepted that only foods that may irritate or get caught in the
diverticula cause problems. Foods such as nuts, popcorn hulls, and
sunflower, pumpkin, caraway, and sesame seeds should be avoided. The seeds
in tomatoes, zucchini, cucumbers, strawberries, and raspberries, as well
as poppy seeds, are generally considered harmless. People differ in the
amounts and types of foods they can eat. Decisions about diet should be
made based on what works best for each person. Keeping a food diary may
help identify individual items in one's diet.
If cramps, bloating, and constipation are problems, the doctor may
prescribe a short course of pain medication. However, many medications
affect emptying of the colon, an undesirable side effect for people with
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Treatment for diverticulitis focuses on clearing up the infection and
inflammation, resting the colon, and preventing or minimizing
complications. An attack of diverticulitis without complications may
respond to antibiotics within a few days if treated early.
To help the colon rest, the doctor may recommend bed rest and a liquid
diet, along with a pain reliever.
An acute attack with severe pain or severe infection may require a
hospital stay. Most acute cases of diverticulitis are treated with
antibiotics and a liquid diet. The antibiotics are given by injection into
a vein. In some cases, however, surgery may be necessary.
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If attacks are severe or frequent, the doctor may advise surgery. The
surgeon removes the affected part of the colon and joins the remaining
sections. This type of surgery, called colon resection, aims to keep
attacks from coming back and to prevent complications. The doctor may also
recommend surgery for complications of a fistula or intestinal
If antibiotics do not correct an attack, emergency surgery may be
required. Other reasons for emergency surgery include a large abscess,
perforation, peritonitis, or continued bleeding.
Emergency surgery usually involves two operations. The first surgery
will clear the infected abdominal cavity and remove part of the colon.
Because of infection and sometimes obstruction, it is not safe to rejoin
the colon during the first operation. Instead, the surgeon creates a
temporary hole, or stoma, in the abdomen. The end of the colon is
connected to the hole, a procedure called a colostomy, to allow normal
eating and bowel movements. The stool goes into a bag attached to the
opening in the abdomen. In the second operation, the surgeon rejoins the
ends of the colon.
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- Diverticulosis occurs when small pouches, called diverticula, bulge
outward through weak spots in the colon (large intestine).
- The pouches form when pressure inside the colon builds, usually
because of constipation.
- Most people with diverticulosis never have any discomfort or
- The most likely cause of diverticulosis is a low-fiber diet because
it increases constipation and pressure inside the colon.
- For most people with diverticulosis, eating a high-fiber diet is the
only treatment needed.
- You can increase your fiber intake by eating these foods: whole
grain breads and cereals; fruit like apples and peaches; vegetables like
broccoli, cabbage, spinach, carrots, asparagus, and squash; and starchy
vegetables like kidney beans and lima beans.
- Diverticulitis occurs when the pouches become infected or inflamed
and cause pain and tenderness around the left side of the lower
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International Foundation for Functional Gastrointestinal
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