title: The oral microbiome of patients with axial spondyloarthritis compared to healthy individuals.
abstract: Background. A loss of mucosal tolerance to the resident microbiome has been postulated in the aetiopathogenesis of spondyloarthritis, thus the purpose of these studies was to investigate microbial communities that colonise the oral cavity of patients with axial spondyloarthritis (AxSpA) and to compare these with microbial profiles of a matched healthy population. Methods. Thirty-nine participants, 17 patients with AxSpA and 22 age and gender-matched disease-free controls were recruited to the study. For patients with AxSpA, disease activity was assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). All participants underwent a detailed dental examination to assess oral health, including the presence of periodontal disease assessed using probing pocket depth (PPD). Plaque samples were obtained and their bacterial populations were profiled using Ion Torrent sequencing of the V6 region of the 16S rRNA gene. Results.Patients with AxSpA had active disease (BASDAI 4.1 ± 2.1 [mean ± SD]), and a significantly greater prevalence of periodontitis (PPD ≥ 4 mm at ≥4 sites) than controls. Bacterial communities did not differ between the two groups with multiple metrics of α and β diversity considered. Analysis of operational taxonomic units (OTUs) and higher levels of taxonomic assignment did not provide strong evidence of any single taxa associated with AxSpA in the subgingival plaque. Discussion. Although 16S rRNA gene sequencing did not identify specific bacterial profiles associated with AxSpA, there remains the potential for the microbiota to exert functional and metabolic influences in the oral cavity which could be involved in the pathogenesis of AxSpA.
authors.affiliation: Department of Microbiology and Immunology, Western University, London, Ontario, Canada; Canadian Centre for Human Microbiome and Probiotic Research, Lawson Health Research Institute, London, Ontario, Canada.
authors.forename: Jordan E
authors.initials: JE
authors.lastname: Bisanz
authors.affiliation: School of Dentistry, University of Otago , Dunedin , New Zealand.
authors.forename: Praema
authors.initials: P
authors.lastname: Suppiah
authors.affiliation: School of Dentistry, University of Otago , Dunedin , New Zealand.
authors.forename: W Murray
authors.initials: WM
authors.lastname: Thomson
authors.affiliation: School of Dentistry, University of Otago, Dunedin, New Zealand; Sir John Walsh Research Institute, University of Otago, Dunedin, Otago, New Zealand.
authors.forename: Trudy
authors.initials: T
authors.lastname: Milne
authors.affiliation: Dunedin School of Medicine, University of Otago , Dunedin , New Zealand.
authors.forename: Nigel
authors.initials: N
authors.lastname: Yeoh
authors.affiliation: Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; Oral Health, AUT, Auckland, New Zealand.
authors.forename: Anita
authors.initials: A
authors.lastname: Nolan
authors.affiliation: Department of Microbiology and Immunology, Western University, London, Ontario, Canada; Canadian Centre for Human Microbiome and Probiotic Research, Lawson Health Research Institute, London, Ontario, Canada.
authors.forename: Grace
authors.initials: G
authors.lastname: Ettinger
authors.affiliation: Department of Microbiology and Immunology, Western University, London, Ontario, Canada; Canadian Centre for Human Microbiome and Probiotic Research, Lawson Health Research Institute, London, Ontario, Canada; Division of Urology, Department of Surgery, University of Western Ontario, London, Ontario, Canada.
authors.forename: Gregor
authors.initials: G
authors.lastname: Reid
authors.affiliation: Canadian Centre for Human Microbiome and Probiotic Research, Lawson Health Research Institute, London, Ontario, Canada; Department of Biochemistry, University of Western Ontario, London, Ontario, Canada.
authors.forename: Gregory B
authors.initials: GB
authors.lastname: Gloor
authors.affiliation: Department of Microbiology and Immunology, Western University, London, Ontario, Canada; Canadian Centre for Human Microbiome and Probiotic Research, Lawson Health Research Institute, London, Ontario, Canada; Division of Urology, Department of Surgery, University of Western Ontario, London, Ontario, Canada.
authors.forename: Jeremy P
authors.initials: JP
authors.lastname: Burton
authors.affiliation: School of Dentistry, University of Otago, Dunedin, New Zealand; Sir John Walsh Research Institute, University of Otago, Dunedin, Otago, New Zealand.
authors.forename: Mary P
authors.initials: MP
authors.lastname: Cullinan
authors.affiliation: Dunedin School of Medicine, University of Otago , Dunedin , New Zealand.
authors.forename: Simon M
authors.initials: SM
authors.lastname: Stebbings
keywords: Axial spondyloarthritis; Microbiome; Oral cavity; Periodontal disease