H

heartburn See DYSPEPSIA.

Helicobacter pylori The BACTERIAresponsible for
much PEPTIC ULCER DISEASEand STOMACH CANCER.
Researchers isolated H. pyloriin 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 INFECTIONoccurs early in life in most peo-
ple. The bacteria establish themselves in the lining
of the STOMACHin the area called the pylorus, and
often in the DUODENUM(first segment of the SMALL
INTESTINE) as well. The presence of H. pyloricauses
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 INFLAMMATIONresults 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 swal-
lows a capsule containing urea tagged with a car-
bon 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. pyloriantigens are other methods
to diagnose H. pylori infection. As well, these
tests show whether treatment with ANTIBIOTIC
MEDICATIONShas successfully eradicated the bac-
teria.
H. pylori are sensitive to several antibiotics
though have the ability to rapidly adapt and
develop resistance. For this reason doctors pre-
scribe two kinds of antibiotic medications in com-

bination. Treatment also includes PROTON PUMP

INHIBITOR (PPI) MEDICATIONS or H 2 ANTAGONIST

(BLOCKER) MEDICATIONSto suppress gastric acid pro-

duction, which makes the stomach a more hostile

environment for the H. pyloriand reduces irrita-

tion to the inflamed tissues or ulcers. H. pyloriare

also sensitive to the commonANTIDIARRHEAL MED-

ICATION bismuth subsalicylate (Pepto-Bismol).

There are numerous treatment protocols for eradi-

cating H. pylori that use these medications in vari-

ous combinations. Once eradicated, H. pyloriseem

not to recur.

See also ANTIBODY; ANTIGEN; CANCER RISK FACTORS;

ENDOSCOPY; GASTRITIS.

hemorrhoids Veins and related structures in and

around the ANUSthat distend and swell. Hemor-

rhoids can be internal or external. An old term for

hemorrhoids that remains in common use is piles,

a reference to the appearance of external hemor-

rhoids. Hemorrhoids alone do not cause symp-

toms; about two thirds of adults in the United

States have hemorrhoids. Hemorrhoids cause PAIN,

itching, and bleeding when they become

inflamed, develop BLOODclots, or prolapse (pro-

trude). Factors that contribute to symptomatic

hemorrhoids include

• chronic CONSTIPATIONand 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)

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