Helicobacter pylori infection is quite common. In the United States, p
revalence varies considerably with race, nationality, socio-economic s
tatus and location of residence. In Western countries, the prevalence
of the infection has shown a steady increase with increasing age. H. p
ylori has been shown to cause chronic gastritis. Most patients infecte
d with H. pylori are asymptomatic and require no therapy. The precise
role of the infection in the pathogenesis of peptic ulcer disease is u
nknown. However, H. pylori infection is associated with a high recurre
nce rate of both gastric and duodenal ulcers. Eradication of the infec
tion reduces the recurrence rate. Once H. pylori infection is acquired
, it usually persists for years, possibly for the patient's lifetime.
Although a causative role in gastric cancer has not been proved, evide
nce suggests an association between H. pylori infection and well-diffe
rentiated gastric adenocarcinoma and gastric lymphoma.