Scientific article
Open access

A potential role for chlamydial infection in rheumatoid arthritis development

Published inRheumatology, kead682
Publication date2023-12-13
First online date2023-12-13

Objectives: To assess the relationship between self-reported and serologic evidence of prior chlamydial infection, rheumatoid arthritis (RA)-related autoantibodies and risk of RA-development.

Methods: This is a nested study within a prospective Swiss-based cohort including all first-degree relatives of RA patients (RA-FDR) who answered a question on past chlamydial infections. Primary outcome was systemic autoimmunity associated with RA (RA-autoimmunity) defined as positivity for anti-citrullinated peptide antibodies (ACPA) and/or rheumatoid factor (RF). Secondary outcomes were high levels of RA-autoimmunity, RA-associated symptoms and RA-autoimmunity, and subsequent seropositive RA diagnosis. We conducted a nested case-control analysis by measuring the serological status against Chlamydia trachomatis' major outer membrane protein. We replicated our analysis in an independent United States-based RA-FDR cohort.

Results: Among 1231 RA-FDRs, 168 (13.6%) developed RA-autoimmunity. Prevalence of self-reported chlamydial infection was significantly higher in individuals with RA-autoimmunity compared with controls (17.9% vs 9.8%, OR = 2.00, 95%CI: 1.27-3.09, p < 0.01). This association remained significant after adjustments (OR = 1.91, 95%CI: 1.20-2.95). Stronger effect sizes were observed in later stages of RA development. There was a similar trend between a positive C. trachomatis serology and high levels of RA-autoimmunity (OR = 3.05, 95% CI: 1.10-8.46, p= 0.032). In the replication cohort, there were significant associations between chlamydial infection and RF positivity and incident RA, but not anti-CCP positivity.

Conclusions: Self-reported chlamydial infections are associated with elevated RA-autoimmunity in at risk individuals. The differing association of chlamydial infections and ACPA/RF between cohorts will need to be explored in future studies but is consistent with a role of mucosal origin of RA-related autoimmunity.

  • Chlamydia trachomatis
  • Chlamydiales
  • RA autoimmunity
  • Rheumatoid Arthritis (RA)
  • Chlamydial infections
  • First-degree relatives (FDR)
  • Intracellular bacteria
  • Pre-clinical stages
  • Serology
Citation (ISO format)
LAMACCHIA, Céline et al. A potential role for chlamydial infection in rheumatoid arthritis development. In: Rheumatology, 2023, p. kead682. doi: 10.1093/rheumatology/kead682
Main files (2)
Article (Published version)
Article (Accepted version)
Secondary files (1)
ISSN of the journal1462-0324

Technical informations

Creation12/21/2023 2:50:11 PM
First validation04/23/2024 2:48:28 PM
Update time04/23/2024 2:48:28 PM
Status update04/23/2024 2:48:28 PM
Last indexation05/06/2024 6:27:06 PM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack