Aims-To investigate the prevalence of Helicobacterpylori in the saliva ofpatients infected with this bacterium. Methods-A novel polymerase chain reaction (PCR) assay was developed to detect Hpylori in saliva and gastric biopsy specimens from patients undergoing endoscopy. Results-Our PCR assay amplified a 417 base pair fragment of DNA from all 21DNAs derived from H pylon clinical isolates but did not amplify DNA from 23 non-H pylon strains. Sixty three frozen gastric biopsy and 56 saliva specimens were tested. H pylon specific DNA was detected by PCR in all 39 culture positive biopsy specimens and was also identified from another seven biopsy specimens which were negative by culture but positive by histology. H pylon specific DNA was identified by PCR in saliva specimens from 30 (75%) of 40 patients with H pylori infection demonstrated by culture or histological examination, or both, and in three patients without H pylon infection in the stomach. Conclusion-The results indicate that the oral cavity harbours H pylon and may be the source of infection and transmission. (J Clin Pathol 1995;48:662-666)

Helicobacter pylori was grown in low numbers from the saliva of one of nine patients who were positive for gastric H. pylori. The saliva-derived isolate from this patient was identical to the antral biopsy-derived isolate from the same patient and differed from isolates cultured from the antral biopsies of all other patients by soluble-protein electrophoresis, restriction endonuclease DNA analysis, and Southern blot hybridization. This is the first observation, to our knowledge, of the recovery of viable H. pylori from saliva.

We have recently developed a new PCR assay for the detection of H. pylori. In this study, the polymerase chain reaction (PCR) assay was used to detect H. pylori in 88 gastric biopsy, 85 saliva, and 71 fecal specimens from 88 patients. H. pylori infection was confirmed in 71 of 88 patients by culture and/or histological stain of gastric biopsies. Serum IgG antibody to H. pylori was also measured and resulted in 97% sensitivity and 94% specificity. H. pylori DNA was detected by the PCR assay in gastric biopsy specimens from all 71 patients (100% sensitivity) with proven gastric H. pylori infection but not from 17 noninfected patients (100% specificity). In saliva specimens, H. pylori DNA was identified in 57 of the 68 patients (84%) with proven gastric H. pylori infection and in three of the 17 patients without gastric H. pylori infection. However, the PCR assay was only able to detect H. pylori DNA in the feces from 15 of 61 patients (25%) with proven gastric H. pylori infection and one of the 10 patients without gastric H. pylori infection. The results show that the PCR assay is reliable for detecting the presence of H. pylori in gastric biopsy and saliva specimens. The data indicate that H. pylori exists in a higher prevalence in saliva than feces and that the fecal-oral route may be an important means of transmission of this infection in developing countries but not as significant as previously suspected in the developed countries. It is likely that the oral-oral route is more prominent.

Helicobacter pylori can be isolated from oro-gastric secretions. Surgical personnel through their clinical practice are exposed to oro-gastric secretions either directly or in aerosolized form during oro-gastric examination and are at an increased risk of this occupationally acquired infection. The sero-prevalence of Helicobacter pylori antibodies in 70 surgical personnel was examined and found to be higher than a published control group. This may suggest that surgical personnel, through their practice, are at increased risk of infection, which poses important public and occupational health problems and may call for precautionary guidelines in clinical practice to prevent occupational infection and vector carriage.