Marcadores de virulência do Helicobacter pylori em crianças e adolescentes residentes em uma comunidade de Fortaleza

Abstract

The Helicobacter pylori infect about half of the world’s population and is related to the development of gastric disorders. The infection is generally acquired during childhood and the bacterium demonstrates a high level of genotypic diversity, the expression of various genes that confer greater virulence strains. The aim of this study was to evaluate genetic markers of virulence of H. pylori strains in children and adolescents resident in the Community Parque Universitario in Fortaleza, Ceara. The gastric juice, for the culture and the DNA extraction of H. pylori, was collected from Enterotest. The genotyping of strains was carried out by the PCR technique. We evaluated 94 individuals, of which 61 (64.9%) H. pylori positive by culture and PCR for gene ureA, 30 (49.2%) males and 31 (50.8%) females. The age ranged 08-18 years, mean age of 12,82 + 3,052. The prevalence of genotypes was: 50/61 (82.0%) cagA, 26/61 (42.6%) cagE, 18/61 (29.5%) babA2, 14/61 (23.0%) homA, 13/61 (21.3%) homB, 31/61 (50.8%) homA/homB. There was no significant association of H. pylori genotypes with the genre, neither with age range of individuals. There was also no association of cagA with other genotypes, although it noted a strong association with homB (p = 0.057). The prevalence of cagE, babA2, and hom was much lower than that described in the literature for children and symptomatic adults, suggesting that, after infection in childhood, the individual strains may change during the course of infection.