Helicobacter pylori (H.pylori)
was first discovered in the stomachs of patients with gastritis &
stomach ulcers by Dr Barry J. Marshall and Dr J. Robin Warren of
Perth, Western Australia. Around 1982 to 1983 the conventional
thinking was that no bacterium can live in the human
stomach as the stomach produced extensive amounts of acid which
was similar in strength to the acid found in a car-battery.
Marshall & Warren literally “re-wrote” the text-books with
reference to what causes gastritis & gastric ulcers.
In recognition of their very important discovery, they were
Awarded the 2005 Nobel Prize for Medicine & Physiology.
Helicobacter pylori is a spiral shaped bacterium that lives in
the stomach and duodenum (section of intestine just below
stomach). It has a unique way of adapting in the harsh environment
of the stomach.
The inside of the stomach is bathed in about half a gallon of
gastric juice every day. Gastric juice is composed of digestive
enzymes and concentrated hydrochloric acid, which can readily tear
apart the toughest food or microorganism. Bacteria, viruses, and
yesterdays steak dinner are all consumed in this deadly bath of
chemicals. It used to be thought that the stomach contained no
bacteria and was actually sterile, but Helicobacter pylori changed
that.
The stomach is protected from its own gastric juice by a thick
layer of mucus that covers the stomach lining. Helicobacter pylori
takes advantage of this protection by living in the mucus lining.
Once H. pylori is safely ensconced in the mucus, it is able to
fight the stomach acid that does reach it with an enzyme it
possesses called urease. Urease converts urea, of which there is
an abundant supply in the stomach (from saliva and gastric
juices), into bicarbonate and ammonia, which are strong bases.
This creates a cloud of acid neutralizing chemicals around the H.
pylori, protecting it from the acid in the stomach. The reaction
of urea hydrolysis is important for diagnosis of H.pylori by the
breath test.
Another defense H. pylori has is that the body's natural
defenses cannot reach the bacterium in the mucus lining of the
stomach. The immune system will respond to an H. pylori infection
by sending white cells, killer T cells, and other infection
fighting agents. However, these potential H. pylori eradicators
cannot reach the infection, because they cannot easily get through
stomach lining. They do not go away either, though, and the immune
response grows and grows. Polymorphs die, and spill their
destructive compounds (superoxide radicals) on stomach lining
cells. Extra nutrients are sent to reinforce the white cells, and
the H. pylori can feed on this. within a few days, gastritis and
perhaps eventually a peptic ulcer results. It may not be H. pylori
itself which causes peptic ulcer, but the inflammation of the
stomach lining; i.e. the response to H. pylori.
H. pylori is believed to be transmitted orally. Many researchers
think that H, pylori is transmitted orally by means of fecal
matter through the ingestion of waste tainted food or water. In
addition, it is possible that H. pylori could be transmitted from
the stomach to the mouth through gastro-esophagal reflux (in which
a small amount of the stomach's contents is involuntarily forced
up the esophagus) or belching, common symptoms of gastritis. The
bacterium could then be transmitted through oral contact
Helicobacter
pylori can cause peptic ulcer
disease and gastric cancer.Carriage
of H.pylori has epidemiological significance in developing
countries where gastric adenocarcinoma is a common cause of
deaths.
However, H.pylori has co-evolved with its
human host over millennia. It can therefore be argued that its not
necessary to prevent or eliminate H pylori colonization. In fact,
the absence of H. pylori appears to increase the risk of
developing GERD and oesophageal adenocarcinoma.
The incidences of H pylori, colonization,
peptic ulceration, and gastric carcinoma are dropping in developed
countries. Thus epidemiological prevention is not necessary.
Don't worry If you are tested positive for
H. pylori and you do not have gastric ulcer. Chances are you do
not need to eradicate the H.pylori. H.pylori is your 'friend' if
the bacterium do not give you any gastric problem.
If you have questions related to this article you may e-mail me
at doctor@soontongkiong.com quoting the contents of the article.
About the author
DR SOON is a medical practitioner. He holds four degrees. MBBS
(University of Malaya), MBA (University of East Asia), LLB (Hons)
(University of Wolverhampton), Master of Medicine (Edith Cowan
University
:
Dr SOON is the owner of AskMyVisitor.com and MyScriptDoctor.com
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on
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