Researchers investigated whether different oral conditions influence colonization of the oral cavity by highly toxigenic Staphylococcus aureus strains. The study was first published online on January 3 in the journal Oral Diseases. The researchers collected samples from cheek, gingival margin, and anterior nares of 45 healthy subjects, 27 periodontitis affected subjects, and 29 subjects with fixed prosthetic restorations, and searched for S aureus. Isolates were screened for 17 genetic determinants and were analyzed to evaluate whether specific characters correlated with oral condition or site of isolation. The study found that the 3 subject groups showed comparable nasal carriage rates, but both the periodontitis and prosthetic restoration groups showed significantly higher oral carriage rates for S aureus, as compared to healthy subjects. Subjects with periodontitis hosted strains possessing a distinct genotypic and phenotypic background, characterized by the presence of a larger number of exotoxins encoding genes. The study results confirm that the oral cavity is an important site of S aureus colonization and demonstrate that conditions modifying the oral environment, such as the presence of periodontitis and of fixed prosthetic restorations, promote S aureus carriage and may favor the spread of more pathogenic strains.
(Source: Passariello C et al. “Influence of oral conditions on colonization by highly toxigenic Staphylococcus aureus strains.” Oral Diseases. First published online January 3, 2012; dio: 10.1111/j.1601-0825.2011.01889.x)
