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AUSTRALIAN GASTROENTEROLOGY INSTITUTE
(educational
arm of the Gastroenterological Society of Australia)
Website: www.gesa.org.au
... Copies reviewed January 2006
HELICOBACTER PYLORI
What is Helicobacter pylori?
Helicobacter pylori (H. pylori)
is a bacterium (germ) that lives in the inner lining of the stomach. It produces
a number of chemicals that damage the lining of the stomach. Once the infection
is present, it persists for many years, if not for life.
How common is Helicobacter pylori infection in
Australia?
About 40% of persons over 40 years of age are
infected with this germ compared to less than 10% of children. Most people are
infected in childhood and in Australia the risk of becoming infected is now much
less than in the past. There is no difference in infection rate between men and
women.
H. pylori is more common in older people and in certain ethnic populations (eg.
Middle Eastern, Asian and Eastern European). In general the germ is more common
in people from a poorer background, people living in institutions (eg. mentally
handicapped) and those who have migrated from countries where infection is more
common, especially the developing world. However, any individual may be
infected.
How do I get it?
The method of infection is unknown. The most
likely is coming in contact with stomach contents of an infected person (by
contact with vomit, sharing foods or eating utensils. Spread between family
members (eg mother and child) is not uncommon. There is no evidence that pets,
farm animals or infected food or water are sources of infection.
How do I know that I have Helicobacter pylori?
1. Breath Tests
Breath tests determine if you are infected by analysing a sample of your
exhaled breath. This is because H. pylori in the stomach is able to convert a
naturally occurring substance called urea into the gas carbon dioxide. If
specially labelled urea is swallowed, labelled carbon dioxide can be detected
for a short time in the breath of an infected individual. There are two types of
tests available. One uses a very small amount of radioactively labelled urea and
the other uses non-radioactive urea. This test is preferable for pregnant women
or children.
Breath tests are accurate, safe, simple and quick to perform. They are
particularly useful to check whether the infection has been successfully
treated. The test accuracy is reduced if you have been taking certain drugs (eg.
antibiotics in the previous month and some ulcer-healing drugs in the previous
1-2 weeks).
2. Blood Tests
These tests can detect current or recent infection. However, the
accuracy of these tests vary and overall they are less accurate than other
methods. They are not useful for checking whether the infection has been
successfully treated
3. Tests requiring gastroscopy
During a gastroscopy (endoscopy) your doctor passes a flexible tube into
your stomach. This allows small samples to be taken from the lining of the
stomach. This is generally safe and painless. The samples are used to detect H.
pylori using a number of methods: It may be seen by looking for it under the
microscope (histology), detecting it with a chemical reaction (rapid urease
test) or growing it in the laboratory (culture). These tests are very accurate,
although recent use of anti-Helicobacter drugs can make them temporarily
unreliable.
What diseases does H. pylori cause?
H. pylori causes:
- Inflammation of the lining of the stomach
(gastritis)
- Stomach (gastric) ulcers
- Duodenal ulcers (ulcers in the first part of the
small bowel)
- Some cancers of the stomach
All people with H. pylori infection have inflammation
of the lining of the stomach. However, most infected people have no symptoms. In
some people, this inflammation progresses to other diseases, but disappears if
the infection is successfully treated.
Peptic Ulcers
An ulcer is a break in the lining of the stomach or upper small bowel, (the
duodenum). Ulcers occurring in these area are often called peptic ulcers.
1. Duodenal
ulcers
H. pylori is the cause of about 90% of ulcers in the duodenum. The
commonest symptom is pain in the upper part of the abdomen. However, it is
important to recognise that pain is often not due to ulcers and some ulcers
cause no symptoms. A small proportion of ulcers cause serious complications such
as bleeding or perforation (bursting).
2. Stomach ulcers
H. pylori is the cause of about 70% of stomach ulcers. Most of the
remaining 30% are due to drugs taken for arthritis (non-steroidal
anti-inflammatory drugs), or aspirin taken to prevent heart attacks or strokes.
Some patients have both risk factors. The symptoms and complications of stomach
ulcers are the same as for duodenal ulcers.
Modern anti-ulcer drugs heal virtually all duodenal and stomach ulcers but there
is a very high chance that the ulcer will come back if H. pylori is not
eliminated. If H. pylori infection is cured, the risk of the ulcer returning is
very low, (unless aspirin or anti-inflammatory drugs needs to be taken).
Cancer of the Stomach
H. pylori infection increases the risk of some forms of cancer of the
stomach. Other factors may also increase this risk (for example a high salt diet
or a low intake of green vegetables in certain populations). Although stomach
cancer is very common in many parts of the world, it is becoming an uncommon
cancer in Australia as the number of people infected declines. It should be
noted that only a small minority of infected people ever develop this problem.
Non-ulcer dyspepsia
Dyspepsia is a word used to describe pain, discomfort or other symptoms in
the upper abdomen. Most people with dyspepsia do not have an ulcer found when
they have tests (eg. gastroscopy) to find the cause of the symptom. If no cause
is found they are described as having 'non-ulcer' dyspepsia. This is a very
common problem and is thought to have many possible causes. Some of these people
have H. pylori infection (many do not) but only in a small number does the pain
subside when the germ is treated.
Should I be tested for Helicobacter pylori?
Duodenal ulcers:
Everyone with a duodenal ulcer should be considered for testing for H.
pylori with a view to treatment if infection is proven. This includes people
with active ulcers and those who have had a duodenal ulcer in the past. If they
are taking anti-ulcer drugs to prevent ulcers coming back and H. pylori is
eliminated, the anti-ulcer drug can often be stopped. There are a few
exceptions, such as when doctor and patient decide that the risk of getting
ulcers again may be unimportant in the context of some other severe illness.
Stomach ulcers:
In the same way, everyone infected with H. pylori who has or has
previously had a stomach ulcer should be considered for testing and treatment.
One exception may be people who develop an ulcer while taking anti-inflammatory
drugs, where the benefits of treating H. pylori infection are more
controversial. In this situation, your doctor can give you individual advice.
Who should be tested for Helicobacter pylori?
In people who have or have had an ulcer, testing and treatment are
important. This is because successful treatment will speed ulcer healing and
prevent ulcers recurring. People with dyspepsia can be considered for testing
also. Some of these people will have ulcers so treatment is important for them
also. In some of the remainder, symptoms may improve with treatment. However, if
they decide to have the infection treated, part of any benefit may be from
reducing the chances of getting ulcers (or possibly stomach cancer) in the
future. In each case the decision to test and by which test should be discussed
with your doctor. Testing should generally not be done unless treatment is
contemplated. The side-effects and cost of treatment need to be weighed against
the possible benefits.
How should Helicobacter pylori be treated?
There is no ideal treatment. A number of drug combinations are used at the
present time. The most effective of these are successful in 80-90% of people.
HOWEVER, THE SUCCESS RATE IS MUCH LOWER IF THE DRUGS ARE NOT TAKEN EXACTLY AS
DIRECTED.
Unfortunately, no single drug is effective against H. pylori. Treatment
combinations include at least three drugs. The use of drug combinations reduces
the risk of H. pylori becoming resistant to treatment. The drugs most commonly
used include ulcer healing drugs (eg. omeprazole. lansoprazole, pantoprazole,
bismuth and ranitidine-bismuth-citrate) and antibiotics (eg. amoxycillin,
clarithromycin, metronidazole, tinidazole and tetracycline). Several combination
packs containing all the drugs needed for a course of treatment are now
available in Australia.
Taking three drugs increases the risk of side effects. Side effects, which may
occur, include nausea, taste disturbances, diarrhoea, skin rashes and
interactions with other medications. Some people taking metronidazole or
tinidazole have an unpleasant reaction to alcohol while they are taking these
antibiotics. Very rarely more serious side effects may occur, such as bacterial
infection of the large bowel (pseudomembranous enterocolitis) or a sudden drop
in blood pressure (anaphylaxis). It is important to tell your doctor if you have
ever had any side effects with antibiotics.
How do I know if the treatment has worked?
If you take the treatment exactly as directed, the chance of success is
high, so it is not always necessary to check that H. pylori has been eliminated
(although many people wish to know). However, H. pylori elimination should be
checked before stopping anti-ulcer drugs especially if you have had a serious
ulcer complication (bleeding or perforation) or if your ulcer has often
recurred. If you have to have another gastroscopy, it is very simple to look for
H. pylori using one of the tests described above. If you do not need another
gastroscopy, your doctor may order a breath test. It is important that these
tests are performed at least four weeks after all treatment is stopped, as H.
pylori can grow again within this time.
If the treatment has not been successful, a different combination of drugs may
be tried.
Am I likely to become infected again?
No, the chance of becoming infected again after successful treatment is only
about 0.5-1.0% per year. This is because most infection is acquired in
childhood.
Do my family members need to be tested if I am
infected?
This is not recommended usually. Occasionally there are special
circumstances and these can be discussed with your doctor.
Further questions
The information given here is current in 1999, but may change in the
future. If you have further questions you should raise them with your own
doctor. There are also Australian Gastroenterology Institute brochures available
on a range of other digestive disorders.
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