Prevalence of Helicobacter pylori and its CagA subtypes in gastric cancer and duodenal ulcer at an Austrian tertiary referral center over 25 years

Abstract

Background and aimsThe prevalence of Helicobacter pylori (H. pylori) tends to be lower in Western countries such as central Europe compared with Asia. The virulence of H. pylori is influenced by its subtype composition, most importantly by the presence or absence of different types of cytotoxin-associated gene A(CagA). This study aimed to assess the prevalence of H. pylori and its respective CagA phenotype in a large retrospective cohort of patients with gastric cancer or duodenal ulcer at a Western tertiary referral institution.MethodsH. pylori positive gastric biopsy samples from patients diagnosed with the afore mentioned diseases within the past 25 years were re-evaluated by histology for H. pylori and status of gastritis. Confirmed H. pylori positive cases were processed for immunohistochemistry (IHC) for H. pylori,CagA, and EastAsiantype CagA.ResultsThe prevalence of H. pylori positive gastric biopsy samples decreased from 20.7% to 2.3% within the study period. Among the gastric cancer patients, the H. pylori positive rate was 16.6%, and didn’t show significant changes over time (p = 0.38). Contrary, the H. pylori positive rate of duodenal ulcer decreased significantlyfrom 40% to 5% (p = 0.01). Within H. pylori positive groups ofboth diseases, CagA was highly detected at IHC (86% and 78%, respectively). Except for a few patients originating from East Asian countries, all CagA detected in this study were of Western type.ConclusionIn this first Western investigation on the chronological prevalence of H. pylori and its most relevant subtypes, Western type of CagA was highly detected in two important index diseases of the pathogen. This raises further questions about the virulence of this subtype.

EPIYA motifs of Helicobacter pylori cagA genotypes and gastrointestinal diseases in the Iranian population: a systematic review and meta-analysis

“…Iran is also a region with a high prevalence of gastric cancer, so that based on GLOBOCAN, the incidence of gastric cancer in this country is estimated at 62.3 cases per 100 000 people. Based on our statistical analysis, the frequency of the cagA gene in the Iranian population was estimated at 54.82%, which confirmed previous findings; the presence of cagA is significantly associated with gastrointestinal diseases such as gastric ulcer, gastric atrophy and gastric cancer [ 52 , 58 , 59 ]. In our project, we also saw a meaningful relationship between the presence of cagA gene and gastric cancer (OR 2.77; p 0.00).…”

What is the Relationship Between Helicobacter Pylori CagA Genotypes and Gastrointestinal Diseases in the Iranian Population? A Systematic Review and Meta-Analysis

“…Based on our statistical analysis, frequency of cagA gene in Iranian population was evaluated about 71.34%, which con rmed previous ndings. In addition, the presence of cagA has a meaningful relationship with gastrointestinal diseases such as peptic ulcer, gastric atrophy, and gastric cancer (54)(55). In our project, also, abundance of cagA positive strains in peptic ulcer and gastric cancer patients was very high, and we also saw a meaningful relationship between the presence of cagA gene and gastric cancer (ORs: 2.277; p-value: 0.00).…”

Review: Epidemiology of Helicobacter pylori infection

“…15 A similar study was performed in Japan 17 demonstrating a continuous decline in the prevalence of H pylori, explained by diminished transmission. 15 A similar study was performed in Japan 17 demonstrating a continuous decline in the prevalence of H pylori, explained by diminished transmission.…”

“…The prevalence of H pylori in biopsies in this highly selective study population decreased from 20.7% to 2.3% within the study period. 15 A similar study was performed in Japan 17 demonstrating a continuous decline in the prevalence of H pylori, explained by diminished transmission. Further projections of this trend for 2050 anticipate a further decline in the prevalence of H pylori and the incidence of gastric cancer.…”