What is Helicobacter pylori?
Helicobacter pylori (H. pylori) is a bacteria which lives only in the lining of
the stomach and is one of the most
common chronic infections in humans.
The importance of H. pylori was unrecognized until 1982, when an
Australian physician, Dr. Barry Marshall, discovered that the germ was almost
always present in patients with
gastritis (inflammation of the stomach)
and ulcers. Doctors now believe that H. pylori is associated with most
stomach ulcers and almost all duodenal ulcers. H. pylori causes inflammation of
the stomach lining and
weakens the natural protection against stomach
acid, which may then cause an ulcer. If stomach acid is
reduced with
medication, an ulcer may heal, but it tends to come back once the medication is
stopped.
However, if H. pylori is treated successfully with
antibiotics, an ulcer can be permanently cured. This means
that ulcer
medications may no longer be needed.
Does H. pylori always cause ulcers?
H. pylori does not always cause ulcers to form but almost always produces
inflammation of the stomach lining.
Some people with H. pylori
infection do not have any symptoms, but many report nausea, gas, bloating, and
burning stomach pain. These symptoms occur twice as often in people with H.
pylori compared to those who
are not infected. Doctors believe that H.
pylori may be responsible for many of these symptoms.
How common is H. pylori infection?
H. pylori infection occurs throughout the world, in every part of society, and
in every age group. About 30% of
the United States population has the
infection, which is more common with advancing age (50% will have it by
age 60) and is rare in children. Once infected with H. pylori, a person usually
continues to carry the germ
unless certain medications are used to cure
the infection.
How did I get it and can I spread it?
H. pylori appears to be passed from person-to-person. It is more common in
spouses of infected patients than
in the general
population. It is
also common in places where sanitation is poor and where crowded living
conditions exist. It is
not clear exactly how a person gets H. pylori,
but it may be through swallowing infected food or water. H. pylori
is
not found naturally in animals, so pets do not seem important in the spread of
the infection. Careful
personal hygiene (through hand washing, use of
separate personal items such as eating utensils, glassware,
etc.)
probably is the best way to reduce person– to –person spread of H. pylori.
How is H. pylori infection diagnosed?
There are several very accurate ways to determine the presence of H. pylori:
1). Blood tests can be used to determine the presence of antibodies to the
bacteria. These tests tell if a
person has ever had the infection but
do not tell if the infection is active.
2) A biopsy of the stomach can
be used to determine the presence of H. pylori. A biopsy is obtained during
an examination of the stomach with a flexible scope. The biopsy is examined by a
pathologist under a
microscope to look for the presence of H.
pylori, or more easily by the CLOtestTM. This slide test checks for the presence
of an enzyme (urease)
produced by H. pylori. A simple color change in
the CLOtestTM confirms that H. pylori is active in the stomach.
3) The
urea breath test is the only diagnostic test that can determine the presence of
H. pylori without the
use of a scope. It is safe, accurate, easy to
perform, and much less expensive than a scope and biopsy for
diagnosis.
How does the urea breath test work?
The urea breath test capsule contains sugar beads coated with small amounts of a
chemical called urea.
Urea is naturally found in the human body, and
the amount in the capsule is much smaller than the head of a
pin. The
urea in the breath test has been “labeled” with a naturally occurring
radioactive tracer called carbon-
14, so it can be detected after it is
taken into the body.
After the capsule is swallowed, it takes about three
minutes to dissolve in the stomach. If the 14C-urea comes
into contact
with H. pylori, it is immediately broken down into 14C-carbon dioxide and
ammonia. The carbon
dioxide enters the bloodstream and is exhaled by
the patient. The 14C-carbon dioxide is usually detectable in
the breath
after 5 minutes. 14C-carbon dioxide excretion peaks between 10 and 15 minutes,
and declines
thereafter with a half-life of about 15 minutes.
Ten minutes after ingesting the capsule, a breath sample is collected in a
balloon. Twenty minutes after
ingestion of the capsule a second sample
is collected in a balloon. The breath samples are then analyzed; if
enough of the 14C is present, the patient has H. pylori. If H. pylori is not
present, the 14C-urea simply washes
through the stomach and is passed
in the urine.
What risks are involved with the Urea Breath Test?
There have been no reported adverse reactions to the urea breath test capsule.
Although the test does
contain a tiny amount of radiation, it is no
more than an average person receives every day (background
radiation).
What instructions must I follow before taking the Urea Breath Test?
1) You must not eat or drink for at least six hours before your test. If you
have taken any antibiotics in the
past month please let your physician
know before taking this test. The test will need to be postponed until you
have been off antibiotics for one month.
2) If your physician has been
giving you a medication called PrilosecTM,PrevcacidTM, AciphexTM,
ProtonixTM, NexiumTM, or CarafateTM, please do not take it for two weeks prior
to your test. Consult your
health care professional for additional
advice.
3) If you have taken Pepto-Bismol, you will need to wait one
month before having this test.
4) Although the radiation dose is
extremely small, the test has not been sufficiently tested in children or
pregnant women. If there is a possibility that you may be pregnant, you may
choose not to have this test
unless you have had a negative pregnancy
test.
How long will the Urea Breath Test take?
The test will take approximately twenty minutes. You will be instructed to
swallow the urea breath test capsule
with a small amount of water and
then blow into a balloon after 10 minutes and again after 20 minutes. You
may resume all normal activities and eat immediately after the test. Results
should be available within a few
business days of completing the test.
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