Background:Idiopathic juvenile arthritis (JIA) is a heterogeneous group of pathologies whose origin remains unknown at present (1). They are characterised by a systemic inflammatory and joint disease affecting children under 16 years of age. The current classification groups the different forms of JIA into 7 distinct entities (systemic forms, polyarticular forms with or without rheumatoid factors, oligoarticular forms, inflammatory arthritis associated with enthesopathies (ERA), arthritis associated with psoriasis and unclassifiable arthritis). Exact etiology of JIA is still unknown. To date, the various hypotheses put forward on the occurrence of JIAs integrate the genetic and environmental framework.The link between periodontal disease and rheumatoid arthritis (RA) is largely reported. Recently, Porphyromonas gingivalis (P. gingivalis) infection explained the occurrence of arthritis in rodent and in RA (2). Several studies mention the beneficial effect of P. gingivalis treatment on disease activity.Currently, there are very few studies on the prevalence of P. gingivalis in patients with JIA and the possible involvement of the germ in the development of inflammatory joint diseases in the pediatric population(3)(4).Objectives:The objective of our study is to determine presence of high IgG antibodies against P. gingivalis and Prevotella Intermedia in a cohort of patients with JIA compared to a control population and to determine variation of level according to sub-classes of JIA.Methods:Sera were obtained from 101 patients satisfying the ILAR classification criteria for JIA and in 25 patients with two other dysimmune disorders (type 1 diabetes and juvenile inflammatory bowel disease). Level of IgG antibodies against P. gingivalis and Prevotella Intermedia were obtained by homemade ELISA already used previously (5).Results:In the JIA group, major children were oligarthritis (47.5%), polyarthritis represents 31.7% of JIAs, ERA and systemic forms of JIA are respectively 9 and 11%. For the control group, 10 (40%) children had diabetes and 15 (60%) had IBD.Levels of anti-P. gingivalis anti-Prevotella Intermedia antibodies were higher in AJI group compared at control groups (P<0.01, P<0.05). Theses difference are mainly related to oligoarthritis and ERA subsets for both P. gingivalis and Prevotella Intermedia.Figure 1.Relative titer of antibodies to P. gingivalis and anti Prevotella intermedia. *: P<0.05; **: P<0.01; ***: P<0.001. P. gingivalis (control vs oligoarthritis p= 0.0032. control vs ERA p= 0.0092). Prevotella intermedia (control vs oligoarthritis p= 0.0194. control vs ERA p= 0.0039).Conclusion:We confirmed high level of anti-P. gingivalis and anti-Prevotella intermedia antibodies in JIA compared to other inflammatory disorders. For the first time, we observed that this high level was mainly in oligoarthritis and ERA. Further investigations are required to investigate involvement of oral dysbiosis in AJI pathogenesis. As observed in RA, it could be a new way to integrate in JIA therapy management.References:[1]Thatayatikom A, De Leucio A. Juvenile Idiopathic Arthritis (JIA). StatPearls Publishing; 2020[2]Cheng Z, Meade J, Mankia K, Emery P, Devine DA. Periodontal disease and periodontal bacteria as triggers for rheumatoid arthritis. Best Pract Res Clin Rheumatol. 2017;31(1):19–30.[3]Romero-Sánchez C, Malagón C, Vargas C, Fernanda Torres M, Moreno LC, Rodríguez C, et al. Porphyromonas Gingivalis and IgG1 and IgG2 Subclass Antibodies in Patients with Juvenile Idiopathic Arthritis. J Dent Child Chic Ill. 2017 May 15;84(2):72–9.[4]Lange L, Thiele GM, McCracken C, Wang G, Ponder LA, Angeles-Han ST, et al. Symptoms of periodontitis and antibody responses to Porphyromonas gingivalis in juvenile idiopathic arthritis. Pediatr Rheumatol Online J. 2016 Feb 9[5]Rinaudo-Gaujous M, Blasco-Baque V, Miossec P, Gaudin P, Farge P, Roblin X, et al. Infliximab Induced a Dissociated Response of Severe Periodontal Biomarkers in Rheumatoid Arthritis Patients. J Clin Med. 2019 May 26;8(5).Disclosure of Interests:None declared.
Peptidylarginine deiminase from Porphyromonas gingivalis citrullinates human fibrinogen and α-enolase: Implications for autoimmunity in rheumatoid arthritis
