Helicobacter pylori and Other Gastric Microbiota in Gastroduodenal Pathologies

The discovery of Helicobacter pylori changed the traditional view of the stomach as a hostile organ to bacterial survival. H. pylori induces chronic gastritis, which has the potential to progress to severe complications such as peptic ulcer disease and gastric neoplasia. The development of modern nucleotide sequencing techniques and new biocomputational tools allow the possibility of studying the diversity and complexity of the microbiome in the whole gastrointestinal (GI) tract and overcome the limitations of culturing techniques. However, the differentiation of alive resident and transient microbes in the upper GI tract and their role in the pathogenesis of gastroduodenal diseases requires an analysis beyond the detection of bacterial genomic material alone. Metabolomic and transcriptomic analyses of the bacteria may add important insights into their interaction with the host. Currently, the interaction of H. pylori with other microbes in the stomach and duodenum and their role for health and disease is poorly understood. This review provides a concise overview on the current knowledge of H. pylori and other gastric microbiota in the relationship with gastroduodenal pathologies.