A NEWLY DEVELOPED PCR ASSAY OF HELICOBACTER-PYLORI IN GASTRIC BIOPSY,SALIVA, AND FECES - EVIDENCE OF HIGH PREVALENCE OF HELICOBACTER-PYLORI IN SALIVA SUPPORTS ORAL-TRANSMISSION

We have recently developed a new PCR assay for the detection of H. pyl ori. In this study, the polymerase chain reaction (PCR) assay was used to detect H. pylori in 88 gastric biopsy, 85 saliva, and 71 fecal spe cimens from 88 patients. H. pylori infection was confirmed in 71 of 88 patients by culture and/or histological stain of gastric biopsies. Se rum IgG antibody to H. pylori was also measured and resulted in 97% se nsitivity and 94% specificity. H. pylori DNA was detected by the PCR a ssay in gastric biopsy specimens from all 71 patients (100% sensitivit y) with proven gastric H. pylori infection but not from 17 noninfected patients (100% specificity). In saliva specimens, H. pylori DNA was i dentified in 57 of the 68 patients (84%) with proven gastric H. pylori infection and in three of the 17 patients without gastric H. pylori i nfection. 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. pylo ri infection and one of the 10 patients without gastric H. pylori infe ction. The results show that the PCR assay is reliable for detecting t he presence of H. pylori in gastric biopsy and saliva specimens. The d ata indicate that H. pylori exists in a higher prevalence in saliva th an feces and that the fecal-oral route may be an important means of tr ansmission of this infection in developing countries but not as signif icant as previously suspected in the developed countries. It is likely that the oral-oral route is more prominent.