Helicobacter pylori and the gastric microbiota

Abstract The human microbiota along the gastrointestinal tract is currently extensively studied and a number of studies focuses on elucidating the association between a more or less diverse intestinal microbial community and health and disease. The human stomach is considered to be exclusively inhabited by Helicobacter pylori and further lacks a colonizing non- H. pylori bacterial flora due to the acidic environment. However, recently a limited number of studies using molecular-based methods have provided a broader picture of the stomach microbiota. The question is whether changes in gastric pH or antibiotic treatment can lead to significant shifts in the stomach microbiota that may be involved in disease development such as gastric cancer.