title: Detection and quantification of five major periodontal pathogens by single copy gene-based real-time PCR.
abstract: Periodontitis is a common chronic multibacterial infection in the tooth-supporting tissues. It has been shown that periodontitis patients carry higher number of disease-associated bacteria than healthy ones. The aim of this study was to generate a novel, single copy gene-based quantitative real-time PCR (qPCR) assay for five major periodontal pathogens - Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, and Tannerella forsythia. The primer/probe sets were designed for conservative lipopolysaccharide-coding gene regions. They proved to be sensitive and able to detect strains representing different serotypes of the target bacteria. The specificity of designed primers was tested using 49 selected bacterial species and no false positive or negative results were observed. We validated the assay with a case-control population, including 165 saliva samples, and proved the diagnostic accuracy by Receiver Operating Characteristic (ROC) curves. All quantified pathogens alone were able to distinguish significantly between the subjects with and without periodontitis, and provided areas under the ROC curve larger than 0.5. The total pathogen burden comprising all five species associated with periodontitis with an area of 0.821 (95% CI, 0.758-0.885, P50.001). Our prominently sensitive and specific assay may have major importance in the diagnosis, prevention, and treatment of periodontitis.
authors: Institute of Dentistry, University of Helsinki, and Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, Helsinki, Finland. kati.hyvarinen@helsinki.fi
authors: Kati
authors: K
authors: Hyvärinen
authors: Saara
authors: S
authors: Laitinen
authors: Susanna
authors: S
authors: Paju
authors: Anne
authors: A
authors: Hakala
authors: Liisa
authors: L
authors: Suominen-Taipale
authors: Mikael
authors: M
authors: Skurnik
authors: Eija
authors: E
authors: Könönen
authors: Pirkko J
authors: PJ
authors: Pussinen
mesh_terms: D000328:Adult; D001438:Bacteroidaceae / Q000235:genetics* / Q000472:pathogenicity; D016022:Case-Control Studies; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis*; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000150:complications / Q000175:diagnosis* / Q000235:genetics / Q000382:microbiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000150:complications / Q000175:diagnosis* / Q000235:genetics / Q000382:microbiology; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000295:instrumentation / Q000379:methods; D012680:Sensitivity and Specificity; D048373:Treponema denticola / Q000235:genetics* / Q000472:pathogenicity
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial