Prevalence of Helicobacter pylori genotypes: cagA, vacA (m1), vacA (s1), babA2, dupA, iceA1, oipA and their association with gastrointestinal diseases. A cross-sectional study in Quito-Ecuador.

BACKGROUND

The most prevalent stomach infection in the world is caused by Helicobacter pylori (H. pylori). Several pathogenicity genes, including cagA, vacA, babA2, dupA, iceA, and oipA, are associated with an increased risk of gastrointestinal disease such as peptic ulcer and stomach cancer. This research aims to determine the prevalence of different H. pylori genotypes and correlate their risk in the development of gastrointestinal diseases in the Ecuadorian population.

METHODS

A cross-sectional research of 225 patients at the Calderón Hospital in Quito, Ecuador, was conducted. End point PCRs were run to determine the presence of 16S rRNA, cagA, vacA (m1), vacA (s1), babA2, dupA, iceA1, and oipA virulence genes. Chi-square test, odds ratios (OR) and 95% confidence intervals (CI) were utilized for the statistical analysis.

RESULTS

H. pylori infection was present in 62.7% of people. Peptic ulcers were seen in 22.2% and malignant lesions in 3.6% of patients. Genes oipA (93.6%), vacA (s1) (70.9%), and babA2 (70.2%) were the most prevalent. cagA/vacA (s1m1) and cagA/oipA (s1m1) combinations were found in 31.2% and 22.7% of the cases, respectively. Acute inflammation has a significant correlation with the genes cagA (OR = 4.96 95% CI: 1.1-22.41), babA2 (OR = 2.78 95% CI: 1.06-7.3), and the cagA/oipA combination (OR = 4.78, 95% CI: 1.06-21.62). Follicular hyperplasia was associated with iceA1 (OR = 3.13; 95% CI: 1.2-8.16), babA2 (OR = 2.56; 95% CI: 1.14-5.77), cagA (OR = 2.19; 95% CI: 1.06-4.52), and the cagA/oipA combination (OR = 2.32, 95% CI: 1.12-4.84). The vacA (m1) and vacA (s1m1) genes were associated with gastric intestinal metaplasia (OR = 2.71 95% CI: 1.17-6.29) (OR = 2.33 95% CI: 1.03-5.24). Finally, we showed that cagA/vacA (s1m1) gene combination increased the risk of duodenal ulcer development (OR = 2.89, 95% CI 1.10-7.58).

CONCLUSION

This study makes a significant contribution by offering genotypic information regarding H. pylori infection. The presence of several H. pylori genes was associated with the onset of gastrointestinal illness in the Ecuadorian population.