RESUMEN
BACKGROUND: Many authors hypothesized that Helicobacter pylori (H. pylori), a causative agent of gastric disease, might act as a potential antigen in salivary glands. H. pylori has been suggested to be transmitted via oral route. METHODS: To investigate the transmission of H. pylori via oral route, saliva samples were taken from the patients with gastric disease. After total DNA was isolated from each saliva sample, amplification of H. pylori urease gene fragment was performed by polymerase chain reaction (PCR) with the isolated DNA as template. PCR-amplified DNA fragments were obtained from seven of 42 patients, the amplified DNA fragments were sequenced by automatic DNA sequencer. Biopsy materials from 2 patients of CLO test-positive with gastric disease were examined and photographed using a light and an electron microscope. RESULTS: The nucleotide sequence of PCR products showed high homology with H. pylori 26695 urease (98%), and the deduced amino acid sequence was identical to the urease alpah subunit of H. pylori J99. The cytosine in the 272th position of urease A nucleotide sequence showed the tendency of high prevalence in the patient with healthy periodontium. Electron micrograph showed helical cell profile of H. pylori on surface epithelial lining cells. CONCLUSION: These results suggest that there might be a transmission of H. pylori via oral route.