Bacteria: Helicobacter pylori

Helicobacter pylori , a Gram-negative microaerophilic bacterium, has a helix-shaped structure. Present in the stomach of healthy individuals, asymptomatic in 50% of the world’s population, H. pylori is a unique bacterium living in an acidic environment (gastric fluid). Its role in gastric ulcers was demonstrated by B Marshall and R Warren in the 1980s (awarded the Nobel Prize in 2005). Helicobacter pylori is responsible for gastro-duodenal ulcers; chronic gastritis, gastric cancer, and adenocarcinoma. Malt gastric lymphoma and few other diseases have also been attributed to H. pylori . Infection is more prevalent in developing countries. Omeprazole (or derivatives) combined with active antibiotics have proven therapeutic efficacy and decreasing incidence in developed countries.