vacA genotypes in oral cavity and Helicobacter pylori seropositivity among adults without dyspepsia.

OBJECTIVE The aims of this research were to determine the prevalence of Helicobacter pylori and its vacA genotypes in oral cavity in persons without dyspepsia and to establish the association between the presence of H. pylori in oral cavity and oral hygiene. The seroprevalence of anti-H. pylori antibodies and its associated factors were analyzed too. STUDY DESIGN For the study, 200 adults without dyspepsia symptoms were selected. Dental plaque and saliva samples from each subject were obtained. H. pylori detection in oral samples was carried out by polymerase chain reaction (PCR) and for vacA genotyping a semi-nested and nested PCR was used. The enzyme-linked immunosorbent assay (ELISA) was used to detect anti-H. pylori IgG and IgM. The data were analyzed with Chi square and Fisher exact test and the statistical significance was set to 0.05. RESULTS Of 200 subjects tested, 124 (62%) were seropositive. H. pylori was detected in the oral cavity of 34 subjects (17%) and vacA allelotypes were typified in 12 of those samples. The s1 allele was detected in 8 (66.7%) samples and in one of them m1 y m2 alleles were found. In four subjects vacA m1 subtypes were found and in two of those both m1 and m2 alleles were detected. The prevalence of H. pylori in oral cavity was higher (18.5%) among seropositive subjects compared with seronegative persons. No association was found between the presence of H. pylori and oral hygiene habits. CONCLUSIONS The presence of H. pylori in oral cavity is more frequent in seropositive subjects without dyspepsia symptoms and could represent the source of gastric infection and bacterial transmission. The data suggest that more than one H. pylori strain may exist in the mouth of asymptomatic persons.