What organism is known to cause peptic ulcer disease?

The organism known to cause peptic ulcer disease is Helicobacter pylori. This bacterium is uniquely adapted to survive in the harsh acidic environment of the stomach, where it can penetrate the protective mucus layer. Once established in the gastric mucosa, Helicobacter pylori can lead to chronic inflammation of the stomach lining (chronic gastritis) and is implicated in the development of peptic ulcers by damaging the mucosal lining and increasing gastric acid secretion.

The relationship between Helicobacter pylori and peptic ulcer disease was first established in the early 1980s when researchers Barry Marshall and Robin Warren demonstrated that this bacterium could cause ulcers in human subjects. Treatment often includes a combination of antibiotics and acid-reducing medications, targeting the eradication of H. pylori to promote healing of the ulcer.

Other organisms listed, such as Streptococcus pneumoniae and Escherichia coli, primarily cause different types of infections and are not associated with peptic ulcer disease. Campylobacter jejuni is known for causing gastrointestinal infections and diarrhea, but it does not play a role in the formation of peptic ulcers.