Helicobacter pylori
Sarah Sutterer

Helicobacter pylori, also known as H. pylori, is a gram-negative, microaeorphillic bacterium that was discovered in 1977.  The bacterium is well known for its ability to inhabit several areas of the human stomach, and from this its ability to cause gastric ulcers and stomach cancer.  However, the strains that appear to cause gastric ulcers seem to be different from those strains which can cause cancer, making it a double whammy.  I chose to study this organism because several relatives of mine suffer from such gastrointestinal diseases as diverticulitis, and the bacterium causes similar symptoms.

H. pylori  can be found in more than 50% of the world’s population, but infection seems to be more prevalent in developing countires (as in most cases of disease).  Researchers have estimated that 20% of all people under the age of 40 and half of all people over the age of 60 carry the bacterium.  Fortunately, most people infected do not develop ulcers, and the cause of this is not yet known, along with how the bacterium is spread.  Some theorys are that contamination of food and water carry the bacteria, or even mouth-to-mouth contact.

In order to infect the individual, the  bacteria uses its flagella to penetrate the stomach lining, and an amazing ability to withstand the acidic pH of the stomach.  This penetration causes inflammation, which eventually may turn into an ulcer or even cancer depending on the strain.  Symptoms of infection are actually very mild, or none at all.  Stomach discomfort is an obvious symptom, one which can be relieved by eating or taking mild medications.  However, once people start experiencing odd stomach symptoms they should see their doctor.  To diagnose a patient with H. pylori, just a simple test can usually be done.  These tests include blood tests, stool tests, and other routine procedures.  A test I found interesting was the urea breath test.  H. pylori has the ability to break down urea into carbon dioxide, which is then tested through something much like a breathalizer, which tests for CO2 levels.  The urea breath test is surprisingly accurate.

Once a person is known to be a carrier for H. pylori, the individual is treated with antibiotics.  In individuals where antibiotic-resistant strands have been found, clinical trials are run in which certain types of drug therapies are used to eradicate the bacterium.  Normally the organism doesn’t cause any long-lasting or life-threatening problems besides the obvious discomfort of a stomach ulcer.  Only in 1-2% of cases is a lifetime risk of stomach ulcers found, so in a healthy, well-off nation an individual has no real fears from H. pylori.

If one has unfounded fears of contamination by Helicobacter pylori, these should be easy to diminish when learning of several famous people who contracted infections from the bacterium during their happy, healthy lives.  George Bush (senior) was known to have a duodenal ulcer which may have been contracted in his time overseas.  Pope John Paul II had gastric bleeding during his reign, which is not incommon, especially since most Poles harbor the bacterium in their bodies.  Several other famous people who suffered from the effects of H. pylori include Alfred Nobel, Charles Darwin, and Stonewall Jackson.  Therefore, it is extremely easy to see that infection by Helicobacter pylori is nothing to worry about (besides a tad bit of discomfort and some nasty stomach symptoms)!

Helicobacter pylori.  ASM Press.  NCBI Bookshelf.  Copyright 2001. http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=hp
Helicobacter pylori.  Lee,Dennis, M.D.  MedicineNet.com  Copyright 1996.  http://www.medicinenet.com/helicobacter_pylori/article.htm
Helicobacter pylori: The Bacteria that Causes Ulcers.  MariAnn.  SteadyHealth.com.  Published 7 May 2006.  http://www.steadyhealth.com/articles/Helicobacter_pylori__The_Bacteria_that_Cause_Ulcers_a71_f0.html
Helicobacter pylori.  Wikipedia.com.  Wikimedia Foundation, Inc.  Modified 17 February 2009.    http://en.wikipedia.org/wiki/Helicobacter_pylori
Microbial Life.  Staley, James T., et al.  Sinauer Associates, Inc: Massachusetts.  2nd Ed.  Copyright 2007.
The Helicobacter Foundation.  Copyright 2006.  http://www.helico.com/

*Disclaimer - This report was written by a student participaring in a microbiology course at the Missouri University of Science and Technology. The accuracy of the contents of this report is not guaranteed and it is recommended that you seek additional sources of information to verify the contents.


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