Characteristic distribution pattern of Helicobacter pylori in dental plaque and saliva detected with nested PCR

The precise mode of transmission and the natural reservoir for Helicobacter pylori are unknown, PCR assays have proved to be highly sensitive and spec ific and are regarded as the method of choice for detecting H. pylori DNA i n the oral cavity, The aim of this study was to investigate the prevalence and distribution of H, pylori in the oral cavity, Forty-two patients underg oing gastroscopy were investigated for the presence of H, pylori in dental plaque and saliva by nested PCR, and in the stomach by the UC-urea breath t est, Samples tested comprised dental plaque from molars, premolars and inci sors and saliva. Two sets of primers homologous to the 860-bp fragment of H , pylori DNA, which have been shown previously to be highly sensitive and s pecific, were used for nested PCR, Eleven patients (26.2%) were infected wi th H. pylori in the stomach, H, pylori DNA was identified in dental plaque samples from 41 patients (97%) and in 23 saliva samples (55%), The prevalen ce in dental plaque from molars, premolars and incisors was 82%, 64% and 59 %, with an odds ratio of 3,18, 1.24 and 1 (reference), respectively, In con clusion, H, pylori was present in the oral cavity of 97% of tested patients , with a characteristic distribution that was independent of the infection status of the stomach. Thus H, pylori may belong to the normal oral microfl ora.