Clinical relevance of Helicobacter pylori sabA genotype in Japanese clinical isolates

Background and Aim:  The clinical outcome of Helicobacter pylori infection is strongly affected by the bacterial genotype. The aim of this study was to assess the relationship between the status of H. pylori sialic acid-binding adhesin (sabA) and the severity of gastric inflammation and diseases. Methods:  Clinical isolates from 108 patients with duodenal ulcer, gastric ulcer, gastric cancer, or chronic gastritis were analyzed by sequencing and PCR assay. The degree of neutrophil infiltration in the antral region was evaluated by histopathological examination. The extent of atrophic change was evaluated using serum pepsinogen levels and the pepsinogen I/II ratio. Results:  Functional sabA was present in 88 (81%) of the 108 patients. Although there was no correlation between the sabA status and gastric diseases, severe neutrophil infiltration and atrophy were associated with functional sabA. Conclusions:  The results show a high prevalence of functional sabA in Japanese clinical isolates. The status of sabA may be an important virulence factor in inducing chronic gastric inflammation.