[The relationship between Helicobacter pylori in oral cavity and the Hp infection in stomach]

Abstract

Objective: To analyze the relationship between Helicobacter pylori (Hp) in oral cavity and the Hp infection in stomach.

Methods: 102 patients with gastric Hp infection and periodontitis were enrolled in this study. DNA was extracted from subgingival plaques, mouthwashes and stomach mucosa samples by using the glass-milk (SiO2) purification method. To identify the presence of Hp in these samples, PCR (polymerase chain reaction) was carried out, and two pairs of oligonucleotide primer were used to amplify a portion of gene urease C and gene cag A of Hp.

Results: The rate of Hp detected in oral cavity was significantly higher in patients with positive Hp in stomach (43.1%, n=58) than in those with negative Hp in stomach (22.7%, n=44, P<0.05). After the treatment for gastric Hp infection for 4 weeks, the eradication rate of Hp in stomach was lower, but only slightly in patients with positive oral Hp (16/25, 64%) than in those with negative oral Hp (24/33, 72.7%). However, this difference became apparent (36.0% vs 63.6%, P<0.05) after one year of the treatment.

Conclusions: The effectiveness of the eradication therapy for gastric Hp infection is affected by the presence of Hp in oral cavity. Oral colonization of Hp may imply that there is a risk of the relapses of gastric and duodenal Hp infection and ulcer after the antibiotics treatment for the eradication of Hp.