Helicobacter pylori is considered the highest independent risk factor for Gastric Cancer along with its sequel Atrophic Gastritis. H. pylori causes chronic gastritis, peptic and duodenal ulcer disease, gastric MALT-lymphoma and adenocarcinoma through a defined pathogenesis known as Correa's Cascade.
The epidemiology of infection by Helicobacter pylori has been characterised in western industrial nations by a linear increase with age. In developing countries a large number of children and juveniles is affected.
Modern methods for the diagnosis of Helicobacter pylori infection are very sensitive and highly specific, but some include either invasive sampling or require special technical procedures. One method which is recommended by NICE as part of the investigation and management of Dyspepsia in Adults involves detection of Helicobacter pylori antigen from faecal samples. This cost-efficient methodology provides a reliable result without the loss of sensitivity or specificity and does not require invasive sampling.
As with all diagnostic tests, certain assays have limitations relating to the clinical circumstance and so it is important to recognise when H. pylori Stool Antigen tests should be used. For example, it has been shown that in cases of bleeding peptic ulcers, proton-pump inhibitor (PPI) and/or antibiotic use, and in cases of atrophic gastritis, H. pylori Stool Antigen tests lose clinical sensitivity and so when such cases are suspected it is recommended to use a test that is more suitable to diagnosis of H. pylori and atrophic gastritis (e.g. GastroPanel).