USE OF THE POLYMERASE CHAIN-REACTION TO DETECT HELICOBACTER-PYLORI IN THE DENTAL PLAQUE OF HEALTHY AND SYMPTOMATIC INDIVIDUALS

A polymerase chain reaction (PCR) assay, based on the amplification of a species specific ureA (urease) gene internal sequence, was used to detect Helicobacter pylori. Total DNA extracts were obtained from dental plaque in patients attending an endoscopy clinic and from apparently healthy schoolchildren of Bangladeshi origin. Of the 54 samples of dental plaque from endoscopy patients examined, 39 were positive (72 per cent). There was 63 per cent correlation (34/54) between H. pylori in the stomach and apparent H. pylori in dental plaque. Seventy-four per cent (29/39) of gastric biopsy culture positive individuals were dental plaque PCR positive. Nine patients had positive plaque PCR, but were negative for gastric culture. In asymptomatic schoolchildren, 58 per cent (11/19) had positive dental plaque PCR results. The results suggest that H. pylori is present in dental plaque at high frequency and PCR of dental plaque may provide a strategy for studying transmission of H. pylori.