SAT0499\u2005ORAL MICROBIOME IN CHILDREN WITH JUVENILE IDIOPATHIC ARTHRITISIN RELATION TO DISEASE STATUS, TEMPOROMANDIBULAR JOINT ARTHRITIS AND MEDICATION: A NORWEGIAN 2-YEAR PROSPECTIVE STUDY

Abstract

Background: Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease in children, with an annual incidence of 1-2 per 1000 children. The temporomandibular joint (TMJ) is involved in 40-70%. The human microbiome might be a potential contributing factor to the development of JIA. Objectives: To describe the oral salivary microbiome in children with JIA and relate this to disease activity, TMJ arthritis, and systemic medications. Methods: 93 children; JIA (n=59), Healthy (n=34) were recruited. Demographics, disease activity, presence of TMJ-arthritis and type of medication was collected in this Norwegian prospective study (www.norjia.com). 116 saliva samples were analyzed using Next Generation Sequencing, V1-V3 region of the 16S rRNA gene, coupled with BLASTn-based, species-level taxonomy assignment algorithm. Downstream bioinformatics analysis was performed with QIIME and LEfSe. Results: Mean age for healthy group (n=34; 27 females) is 12.3 ±3.0 years while for the JIA group (n=59; 43 females) the mean age is 12.6±2.7 years. A total of 541 bacterial species belonging to 111 genus and 10 phyla were identified, with Prevotella, Streptococcus, Actinomyces, Rothia Haemophilus and Veillonella accounting for the bulk of the average microbiome. There were no significant difference between JIA and healthy subjects in species richness and alpha diversity. However, differential abundance analysis revealed genera TM7-G1, Solobacterium and Mogibacterium to be associated with JIA, while Haemophilus and Lactococcus to be overabundant in healthy subjects. Conclusion: It seems that taxa associated with chronic inflammation were found to be enriched in the saliva of JIA patients. References [1] Frid P, Nordal E, Bovis F, Giancane G, Larheim TA, Rygg M, et al. Temporomandibular Joint Involvement in Association With Quality of Life, Disability, and High Disease Activity in Juvenile Idiopathic Arthritis. Arthritis Care Res (Hoboken). 2017;69:677-86. Disclosure of Interests: None declared