BackgroundPeriodontitis results from the interaction between a subgingival biofilm and host immune response. Changes in biofilm composition are thought to disrupt homeostasis between the host and subgingival bacteria resulting in periodontal damage. Chronic systemic inflammatory disorders have been shown to affect the subgingival microbiota and clinical periodontal status. However, this relationship has not been examined in subjects with systemic lupus erythematosus (SLE). The objective of our study was to investigate the influence of SLE on the subgingival microbiota and its connection with periodontal disease and SLE activity.MethodsWe evaluated 52 patients with SLE compared to 52 subjects without SLE (control group). Subjects were classified as without periodontitis and with periodontitis. Oral microbiota composition was assessed by amplifying the V4 region of 16S rRNA gene from subgingival dental plaque DNA extracts. These amplicons were examined by Illumina MiSeq sequencing.ResultsSLE patients exhibited higher prevalence of periodontitis which occurred at a younger age compared to subjects of the control group. More severe forms of periodontitis were found in SLE subjects that had higher bacterial loads and decreased microbial diversity. Bacterial species frequently detected in periodontal disease were observed in higher proportions in SLE patients, even in periodontal healthy sites such as Fretibacterium, Prevotella nigrescens, and Selenomonas. Changes in the oral microbiota were linked to increased local inflammation, as demonstrated by higher concentrations of IL-6, IL-17, and IL-33 in SLE patients with periodontitis.ConclusionsSLE is associated with differences in the composition of the microbiota, independently of periodontal status.Electronic supplementary materialThe online version of this article (doi:10.1186/s40168-017-0252-z) contains supplementary material, which is available to authorized users.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation. Individuals with RA have a higher risk of periodontitis and periodontitis has been linked to RA through the production of enzymes by periodontal pathogens that citrullinate proteins. This linkage is supported by findings that periodontitis is associated with increased RA severity and treatment of periodontitis can improve the symptoms of RA. The possible mechanism for this association is through dysbiosis of the oral microbiota triggered by RA-induced systemic inflammation. We examined the RA status of subjects by measuring the number of tender and swollen joints, anti-citrullinated protein antibody and rheumatoid factor. Periodontal disease status and salivary cytokine levels were measured, and dental plaque analyzed by 16S rRNA high throughput sequencing. RA patients had a higher bacterial load, a more diverse microbiota, an increase in bacterial species associated with periodontal disease, more clinical attachment loss, and increased production of inflammatory mediators including IL-17, IL-2, TNF, and IFN-γ. Furthermore, changes in the oral microbiota were linked to worse RA conditions. Our study provides new insights into the bi-directional relationship between periodontitis and RA and suggest that monitoring the periodontal health of RA patients is particularly important.

Oral symptoms in systemic lupus erythematosus (SLE) patients are often unexplored and affect the health-related quality of life. The aims of this study were: (a) to evaluate the oral health condition of SLE patients compared to control subjects without rheumatic diseases; (b) to determine the consequences of oral health condition in the quality of life of these two groups. Individuals with SLE ( n = 75) and without SLE ( n = 78) (control group), paired for gender and age, underwent complete oral examination. Sociodemographic and clinical information was obtained, and interviews were conducted using the Brazilian version of the oral health impact profile. The activity and damage of SLE disease were assessed, respectively, by the systemic lupus erythematosus disease activity index 2000 and the Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index for systemic lupus erythematosus. When we analysed the oral health condition and hygiene habits of the participants, SLE patients exhibited an increased number of missing teeth despite their higher frequency of tooth brushing. No significant differences were verified in other habits and clinical parameters evaluated such as smoking, flossing, salivary flux, periodontitis, decayed and filled teeth. Patients with SLE presented with worse oral health-related quality of life than controls ( P = 0.011). The significant difference was on individuals' physical disability ( P = 0.002). The determinant of the negative impact on the oral health-related quality of life was prosthesis wearing ( P < 0.05). Overall, the oral health impact profile score was higher in individuals with moderate SLE damage compared to SLE individuals with no damage ( P = 0.043). Patients with SLE had a negative impact of oral condition on their quality of life. The evaluation of the oral health-related quality of life might be useful to monitor the effects of SLE on oral condition.

The reduction of DAS 28 in patients with rheumatoid arthritis after periodontal treatment suggests that the improvement of periodontal condition is beneficial to these patients. Further randomized controlled clinical trials are necessary to confirm this finding.