Definition of Helicobacter pylori Helicobacter pylori: A
bacterium that causes stomach inflammation (gastritis) and
ulcers in the stomach and duodenum. This bacterium is the most
common cause of ulcers worldwide. H. pylori infection may be
acquired from contaminated food and water or through person-to-
person contact. It is common in people who live in crowded
conditions with poor sanitation. This bacterium is also believed
to be associated with stomach cancer (gastric adenocarcinoma)
and a rare type of lymphoid tumor called gastric MALT lymphoma.
Infected persons usually carry H. pylori indefinitely, often
without symptoms, unless treated with antibiotics to eradicate
the bacterium. Also known as ulcer bug.Source: MedTerms™ Medical
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