Helicobacter pylori (which is
written in an abbreviated form as H. pylori) is a form of bacteria, a bug or germ,
that lives in the sticky fluid (mucus) which coats the lining of the human stomach and
duodenum. It is usually a life-long infection and may cause no problems. However, it is
often associated with peptic ulcer. This leaflet answers questions that you may want to
ask about H. pylori.
What is a peptic ulcer ?
||Peptic ulcers look like mouth ulcers. They
are sensitive raw patches in the lining of the stomach or duodenum (the part of the gut
immediately after the stomach).
What are gastric and duodenal ulcers ?
||Gastric ulcers are ulcers in the stomach,
and duodenal ulcers are those of the duodenum.
Research has shown
that H. pylori is an important cause of peptic ulcers.
Where does H. pylori come from ?
H. pylori is a germ that can only infect human beings. Animals
have similar bacteria, but they cannot infect humans. Hence, H. pylori must pass
from one person to the next.
How do we get infected with H.
It is still not certain how this germ moves from the stomach of one
person to the next. These bacteria are rarely detected in saliva, gastric juice or stools.
The latest theory is that people may be highly infectious for only a matter of days or
weeks - and transmission may be via the fingers when coming into contact with infected
vomit or stools. Good hygiene in the home seems to decrease transmission.
How long does H. pylori infection
This is a life-long infection for most people. Without medical help, the
infected person seems incapable of getting rid of it. Long-term infection, perhaps for up
to 50 years, can result in loss of the stomachs layer of mucus. At that stage, the
infection disappears in some people.
Where does H. pylori live in
the stomach ?
The normal human stomach has a very thin layer of mucus that coats the
whole of its inside surface. This mucus has a protective role, acting as a barrier between
the acid in the stomach and the sensitive stomach wall. The duodenum can also have this
type of mucus, particularly if the stomach secretes a great deal of acid, and in these
people H. pylori can also survive in the lining of the duodenum. H. pylori
has become adapted to live exclusively in this layer of mucus.
How many people are infected with H.
In Britain, about half the population over middle age is infected with H.
pylori. It seems likely that most people get infected in childhood. Probably, almost
all of our grandparents were infected with these bacteria but, because of improved hygiene
in the modern home, very few children are now infected in Britain. Unfortunately, most
children in the developing world still get infected. This means that almost everybody in
these countries has a chronic infection with H. pylori.
What does H. pylori do ?
H. pylori acts as an irritant to the lining of the stomach, and
this causes inflammation of the stomach (gastritis). H. pylori also appears to be
important in the development of peptic ulceration. A combination of factors (including H.
pylori, gastric acid, genetic background, use of aspirin or drugs for arthritis, and
cigarette smoking) may combine to cause ulcers of the stomach or duodenum. It is possible
that a small proportion of people who are infected develop a cancer of the stomach in
later life. This is probably because of the chronic irritation to the lining of the
stomach throughout decades of long-term infection. There is no evidence at present that
eradication of H. pylori in adults will reduce the risk of gastric cancer.
How do we know H. pylori is
an important cause of peptic ulcers ?
Without treatment, almost every ulcer sufferer experiences repeated
episodes of painful ulceration. However, such relapses become extremely rare if H.
pylori is cleared from the stomach by medical treatment. Eradicating H. pylori
infection can give a permanent cure of most gastric and duodenal ulcers.
How can H. pylori infection
be detected ?
When you are infected with H. pylori, you will produce antibodies
to fight against these bacteria. It is possible to detect these antibodies by a blood test
either using a finger prick or a larger blood sample. The bacteria can also be discovered
by taking a sample (a biopsy) of the lining of the stomach during endoscopy. This is a
procedure in which a flexible instrument is passed into the stomach so that its lining can
be seen. A biopsy can be taken and sent for testing in the laboratory. There is also a
rapid urease test in which the endoscopist will perform an immediate analysis in the
endoscopy room. Finally, a breath test (the 13C or 14C Urea Breath Test) may be used. This
test involves swallowing a harmless substance that will be broken down in the stomach, if
bacteria are present. The breakdown products are detected in the breath. This Urea Breath
Test probably provides the most accurate assessment as to whether or not H. pylori
is in the stomach. It is very useful in proving whether treatment has eradicated the
How can a person get rid of H.
pylori infection ?
H. pylori is a bacterium, and it should respond to antibiotics.
Unfortunately, the bacteria have proved very difficult to clear from the human stomach.
This is probably because it is hard to get high concentrations of an antibiotic into the
mucus that lines the stomach. Most treatments involve swallowing several different types
of tablet simultaneously for 7-28 days. These will include one or two antibiotics and also
a drug which controls acid secretion and/or contains bismuth. Almost all H. pylori
infections can be eradicated if the course of treatment is completed. However, the
treatment may cause a range of side effects - particularly abnormal taste, nausea or mild
diarrhoea. Many combination treatments are only for one week but if any of these symptoms
become intolerable, you should contact your doctor. However, the course of treatment
should be completed, if at all possible.
Who should receive treatment to
eradicate H. pylori infection ?
Patients with definite proof of peptic ulceration are the ideal people
to receive treatment to eradicate H. pylori infection. These patients will usually
have a long-term cure of their ulcer disease, if the treatment clears all traces of H.
pylori infection from the stomach. However, if it proves impossible to clear the
stomach, ulcer patients can be protected from relapse by long-term daily treatment with a
drug to decrease gastric acidity.
What about people who are H.
but without any sign of peptic ulceration ?
This type of person is often well with no symptoms and no treatment is
indicated. A person who suffers from indigestion without evidence of a peptic ulcer will
often feel no better after eradication of H. pylori infection.
Should everyone be tested for H.
In the future, it may well be worthwhile to search out every person with
H. pylori infection. However, at the moment we do not have a simple and inexpensive
form of treatment to provide mass eradication of H. pylori infection, nor do we
know that doing so would help people without an ulcer. It is possible that vaccination may
prove the answer, but no vaccines are available against H. pylori at the moment.
What research is needed ?
H. pylori has stimulated an enormous amount of research over the
last 10 years. Many questions remain unanswered - for example, the exact method by which
the germ passes from one person to another, the reasons why it causes peptic ulceration,
and new strategies for eradicating infection using either antibiotics or vaccines.