A Systematic Review of the Correlation Between Microbiome Composition Variations Identified by rRNA Sequencing and Disease Severity in Juvenile Idiopathic Arthritis

Background: Juvenile Idiopathic Arthritis (JIA) is a chronic autoimmune condition in children. Emerging evidence suggests that dysbiosis of the gut and oral microbiome, characterized via ribosomal RNA (rRNA) sequencing, may be linked to disease activity and severity. However, findings are heterogeneous, and no systematic review has comprehensively synthesized the correlation between microbiome composition and validated disease severity measures in JIA. Objective: To systematically review and synthesize current evidence from studies utilizing rRNA sequencing to characterize microbiome composition in JIA patients and assess its correlation with clinical measures of disease severity. Methods: We will search multiple electronic databases for observational studies (cross-sectional, cohort, case-control) that use rRNA sequencing to analyze the microbiome (fecal, oral, or other sites) in JIA patients and report associations with disease severity measures (e.g., JADAS-71, ACR criteria, ESR, CRP). Data will be extracted and a narrative synthesis performed, with summary tables presenting microbial taxa associated with disease states. Expected Outcomes: This review will clarify the nature and strength of the association between microbiome dysbiosis and disease severity in JIA, identify consistent microbial signatures, and highlight gaps for future research.