Association of the presence of Helicobacter pylori in the oral cavity and in the stomach.

UNLABELLED: Helicobacter pylori is a gram-negative, microaerophilic rod-shaped bacteria that lives beneath the gastric mucous layer, on the surface of epithelial cells. Stomach infection with this organism causes inflammation of the gastric mucosa, which can lead to gastritis, duodenal or gastric ulcer and even in rare cases to gastric carcinoma or MALT lymphoma. Approximately 50% of the world's population is believed to be infected with H. pylori. Most infections is probably acquired in childhood, but the exact route of transmission is unknown. It has been speculated that dental plaque might harbour Helicobacter pylori and, therefore, might be a source of gastric infection. In order to address this issue we studied the relationships between oral and gastric infections with H. pylori in 100 subjects.
METHODS: Gastric H. pylori infection was determined by (13)C-urea breath test (UBT) and the presence of the bacteria in oral cavity was monitored by the culture from the saliva and from dental plaque.
RESULTS: H. pylori was found in the stomach in 51% of studied individuals, while oral H. pylori was found in 54% (in saliva) and in 48.3% (in gingival pockets), the difference was not statistical significant (p=NS). Interestingly, anti-Hp IgA was found in 84% of studied individuals. No relationship was found between the presence of the bacteria in the oral cavity and the H. pylori gastric infection. 54.9% of subjects with stomach infection showed concomitant presence of H. pylori in saliva. 52.3% of examined subjects with negative UBT-test revealed the presence of H. pylori in culture from the saliva. The X(2) value of relationship between UBT and culture H pylori in saliva was 0.029 (p=0.9). Similarly, no relationship was found between the presence of H. pylori in the stomach and in the dental plaque (X2=0.6); p=0.4). As expected, the presence of H. pylori in the dental plaque was significantly correlated with the presence of bacteria in the saliva (X2=18.4; p=0.0002). We also compared the presence of H. pylori in the saliva of patients with and without teeth. The cultured H. pylori was found in 63.7% of patients without teeth and in 52.9% of patients with teeth. This indicates that the presence of teeth does not seem to affect the occurrence of H. pylori in saliva. We conclude that oral activity contamination with of H. pylori occurs at similar degree to that in the stomach. However, there was no significant correlation between the occurrence of H. pylori in the stomach and in the oral cavity indicating that other factors, like susceptibility to infection due to acid environment in the stomach may be the major factor in gastric infection with that bacteria, while oral cavity may serve only as transient food-related contamination without clear relation to gastric infection.