Encyclopedia of Health and Medicine

H
heartburn
See DYSPEPSIA.
53
Helicobacter pylori The BACTERIA responsible for
much PEPTIC ULCER DISEASE and STOMACH CANCER.
Researchers isolated H. pylori in 1982, a discovery
that dramatically altered the treatment approach
to ulcers. Though researchers do not know how H.
pylori enter the gastrointestinal system, they
believe INFECTION occurs early in life in most people.
The bacteria establish themselves in the lining
of the STOMACH in the area called the pylorus, and
often in the DUODENUM (first segment of the SMALL
INTESTINE) as well. The presence of H. pylori causes
irritation, which the body counters with an
inflammatory response in an attempt to buffer the
gastric mucosa from the irritation. Over time this
pattern of irritation and INFLAMMATION results in
ulcerative erosions of the mucosa, commonly
called stomach ulcers.
The urea breath test is a simple, accurate, and
fast way for doctors to determine whether H. pylori
are present. The person drinks a solution or swallows
a capsule containing urea tagged with a carbon
isotope. H. pylori metabolize the urea,
releasing carbon dioxide containing the carbon
isotope. A machine analyzes breath samples to
detect the presence of carbon isotopes in the
carbon dioxide. Endoscopic biopsy, blood tests
to detect H. pylori antibodies, and stool tests
that detect H. pylori antigens are other methods
to diagnose H. pylori infection. As well, these
tests show whether treatment with ANTIBIOTIC
MEDICATIONS has successfully eradicated the bacteria.
H. pylori are sensitive to several antibiotics
though have the ability to rapidly adapt and
develop resistance. For this reason doctors prescribe
two kinds of antibiotic medications in combination.
Treatment also includes PROTON PUMP
INHIBITOR (PPI) MEDICATIONS or H2 ANTAGONIST
(BLOCKER) MEDICATIONS to suppress gastric acid production,
which makes the stomach a more hostile
environment for the H. pylori and reduces irritation
to the inflamed tissues or ulcers. H. pylori are
also sensitive to the common ANTIDIARRHEAL MED-
ICATION bismuth subsalicylate (Pepto-Bismol).
There are numerous treatment protocols for eradicating
H. pylori that use these medications in various
combinations. Once eradicated, H. pylori seem
not to recur.
See also ANTIBODY; ANTIGEN; CANCER RISK FACTORS;
ENDOSCOPY; GASTRITIS.
hemorrhoids Veins and related structures in and
around the ANUS that distend and swell. Hemorrhoids
can be internal or external. An old term for
hemorrhoids that remains in common use is piles,
a reference to the appearance of external hemorrhoids.
Hemorrhoids alone do not cause symptoms;
about two thirds of adults in the United
States have hemorrhoids. Hemorrhoids cause PAIN,
itching, and bleeding when they become
inflamed, develop BLOOD clots, or prolapse (protrude).
Factors that contribute to symptomatic
hemorrhoids include
• chronic CONSTIPATION and straining with BOWEL
MOVEMENTS
• sitting on the toilet for extended periods of
time, which reduces blood circulation
• low fiber diet, which results in small, hard
stools that can be difficult to pass
• PREGNANCY, which pressures the pelvic floor and
can affect perineal blood flow
• INFLAMMATORY BOWEL DISEASE (IBD)