Helicobacter Pylori
(H. pylori)

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Medical Author:

Benjamin Wedro, MD, FACEP, FAAEM

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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• Helicobacter Pylori (H. pylori) Overview
• Helicobacter Pylori (H. pylori) Causes
• Helicobacter Pylori (H. pylori) Symptoms
• When to Seek Medical Care
• Exams and Tests
• Helicobacter Pylori (H. pylori) Treatment
• Self-Care at Home
• Prevention
• Outlook
• Synonyms and Keywords
• Authors and Editors
• Read more on Helicobacter Pylori (H. pylori) from Healthwise
• Viewer Comments: Helicobacter Pylori - How Was Diagnosis Established
• Viewer Comments: Helicobacter Pylori - Treatment

Helicobacter Pylori (H. pylori) Overview

Helicobacter pylori (H. pylori) is a type of bacteria responsible for widespread infection with more than 50% of the world's population infected, even though 80% of those infected have no symptoms. H. pylori infection is associated with low grade inflammation of the stomach and duodenum (the first part of the small intestine that empties the stomach).

The bacteria has evolved to survive in the acidic environment of the stomach where enzymes digest food. The H. pylori bacteria burrow into the cells of the stomach lining and cause low grade inflammation. H. pylori is the most common cause of gastric ulcers and gastritis (gastro=stomach +itis=inflammation). Ten percent of those infected may develop an ulcer. Also, those infected have an increased risk of stomach cancer and lymphoma.

Interestingly, the presence of the bacteria may decrease the prevalence of esophagitis by decreasing the amount of stomach acid that refluxes back into the esophagus. This in turn leads to a decreased risk for esophageal cancer in those infected with H. pylori. Further, H. pylori seems to decrease the risk of developing asthma and allergies.

H. pylori bacteria is found most frequently in underdeveloped countries; but with improved economic conditions, the rate of infection in the population decreases. The infection rate in the United States is between 20%-30%, however, it is higher in Hispanics, African Americans, and the elderly.