Diverticulosis
occurs when small defects in the muscle of the wall
of the large intestine or colon allow small pockets
or pouches (diverticula) to form. Diverticulitis is
infection or inflammation of these abnormal pouches.
Together, these conditions are called diverticular
disease. Diverticular disease isn’t associated
with more serious conditions, such as bowel cancer,
despite some similar symptoms.
Causes of diverticulosis
Diverticulosis is extremely common. Old age and diet
may be the most important risk factors. More than
half of all adults over the age of 70 have the
condition. Most of these people are unaware that
they have diverticulosis.
Diverticulosis is less common in people under 50.
Studies appear to show that diverticulosis became
more common in the 20th Century. It is also more
common in ‘Western’ nations including North
America, Europe and Australia. It is less common in
Asia and very uncommon in Africa. Discovery of this
led to the theory that the low fibre diet common in
Western nations may be important. Animal studies
show that this theory is possible. It has also been
shown that vegetarians less commonly develop
diverticulosis. Exactly how a low fibre diet may
cause diverticulosis is not known.
There may also be genetic causes. It is interesting
that Western people develop diverticulosis in the
last third of the colon, while people in Asian
countries - such as Japan, Taiwan and Singapore -
generally develop diverticulosis in the first
section of the colon. In the Japanese population
living in Hawaii, the risk of diverticulosis is
higher than those living in Japan. However, when
diverticulosis develops in these people, it is still
in the ‘Japanese’ location - the first third of
the colon.
Symptoms
Diverticulosis is usually asymptomatic (has no
symptoms). When many diverticula (pouches) are
present, the normal smooth working of the bowel can
be affected. This may cause a range of symptoms
including:
Abdominal pain and bloating.
Constipation and diarrhoea.
Flatulence.
Blood in the faeces - this is usually minor
but, if a diverticulum gets inflamed or is near
a blood vessel, bleeding can sometimes be heavy.
Anaemia from repeated bleeding may occur.
Many of these symptoms are similar to those of bowel
cancer. Diverticulosis is more common, so these
symptoms may be more likely to be due to
diverticulosis than cancer. However, a specialist
will usually assess these symptoms - your doctor
will refer you.
Diverticulitis seems to occur when a small puncture
develops in the diverticular wall. This causes a
small infection to develop, often forming an
abscess. Symptoms include:
Sharp pain, often located at a specific point,
like in the lower left half of the abdomen.
Fever.
Distension (bloating) of the abdomen.
Nausea and vomiting.
Possible complications
Some of the complications of diverticular disease
include:
Abscess - untreated, diverticulitis may
lead to an abscess, which is a ball of pus.
Perforation - a weakened pocket of
bowel wall may rupture. The contents of the
bowel can then seep into the abdominal cavity.
Symptoms include pain, high fever and chills. A
perforated bowel is a medical emergency.
Peritonitis - perforation can lead to
peritonitis (infection of the membranes that
line the abdominal cavity and abdominal organs).
This complication is potentially life
threatening.
Haemorrhage - diverticula can be the
source of haemorrhage. When bleeding occurs, it
is important to exclude other causes. A person
with diverticulosis can also get cancer.
Diagnosis methods
Since diverticulosis is often asymptomatic, it tends
to be discovered during examinations for other
conditions such as colorectal cancer. Diverticulitis
is usually diagnosed during an acute attack. Tests
to confirm the diagnosis of diverticular disease
include:
Medical history - including dietary
habits.
Physical examination - including rectal
examination.
Colonoscopy - a slender flexible tube
is inserted into the anus so that the doctor can
look at the entire length of the large
intestine.
Virtual colonoscopy (CT colonoscopy) -
a small tube is used to gently inflate the colon
and a CT scan is then taken of the abdomen,
outlining the colon.
Barium enema - a special contrasting
dye is flushed into the bowel via the anus, and
then x-rays are taken.
CT scan - to detect abscesses outside
the bowel lining.
Blood tests - to check for signs of
infection.
Stool tests - to check for the presence
of blood in the faeces, or the presence of
infections, which may mimic the symptoms of
diverticulosis and diverticulitis.
Treatment options - diverticulosis
For persons with diverticulosis, there is no proven
way to prevent the formation of new diverticula.
Treatment revolves around the settling of symptoms,
and may include:
A gradual switch to diet with increased
soluble fibre (green vegetables, oat bran, and
fibre supplements such as psyllium) usually
leads to an improvement in bowel habit and mild
symptoms.
Some foods may make symptoms worse, or even
lead to diverticulitis. Nuts, seeds and pips are
best avoided, while some individuals find
avoiding legumes (peas and beans) and sweet corn
also helps.
Short term use of laxatives to treat and
prevent constipation.
Rarely, elective surgery is performed to
remove seriously affected bowel segments when
symptoms are disabling.
Treatment options - diverticulitis
Diverticulitis is often a medical emergency,
requiring immediate medical attention and,
frequently, admission to hospital. Mild attacks can
be treated at home, but should always be assessed
promptly. Treatment may include:
No eating or drinking - intravenous fluids are
given to rest the bowel.
Antibiotics.
Pain-killing medications.
Surgery, if the weakened sections of bowel
wall have ruptured or become obstructed, or if
the attack of infection fails to settle.
If it isn’t possible to rejoin the healthy
sections of bowel, then a colostomy bag will be
fitted. This is more common if the surgery is
performed as an emergency. The use of a
colostomy is generally temporary, and the bowel
can be rejoined after six to 12 months, if
health permits.
The long term use of a mild antibiotic is
often necessary to prevent further attacks.
Self-care suggestions
Suggestions include:
Increase your daily intake of green
vegetables. Introduce fibre gradually to avoid
unpleasant symptoms such as flatulence.
Consider using a fibre supplement (such as
psyllium).
Drink plenty of fluids to ensure your stools
are soft, moist and easy to pass.
Exercise regularly to encourage bowel function
and peristalsis.
Where to get help
Your doctor
Gastroenterologist or specialist surgeon.
Things to remember
Diverticulosis is the formation of abnormal
pouches in the bowel wall.
Diverticulitis is inflammation or infection of
these abnormal pouches.
Together, these conditions are known as
diverticular disease.
A diet low in fibre is a known risk factor for
diverticular disease.
Treatment options include a change of diet,
antibiotics and - rarely - surgery.
