Identification serum CXCL13 chemokine as a novel biomarker in diagnosis of rheumatoid arthritis

Abstract

Background: Rheumatoid arthritis is a systemic inflammatory autoimmune disease, characterized by chronic polyarthritis. The determination of novel biomarkers to RA patients very necessary to facilitate quick diagnosis and management of the disease. Rheumatoid arthritis researchers has a recently discovered biomarker, CXCL13, which can be regarded as part of pathogenesis of RA. Objective: Comparison diagnostic value of CXCL13 Chemokine with Anti-cyclic citrullinated peptide (CCP) antibody in RA patients. Methods: A case control study was carried out during the months of November 2021 and March 2022. 60 patients were obtained from the Rheumatology Unit at Al-Sadr Medical City, and an additional 60 individuals were used as the control group. Laboratory examinations such as ESR and rheumatoid factor (RF) were obtained as routine work for RA patient’s. CXCL13 and Anti-CCP antibodies were measured by enzyme-linked immune-sorbent assay. Results: Most of the patients were women 46(76.7%), making the female-to-male patient ratio (3.2:1). Patients have a greater CXCL-13 concentration (0.913±0.52) compared to healthy controls (0.417±0.28) (P value = 0.000). Moreover, anti-CCP had highest AUC (0.94%) than CXCL13 (0.88%) and RF (0.76%) at significant value is 0.000. The sensitivity of CXCL13 (93%) was the highest and was comparable to anti-CCP (83%) and RF (68%). As regard the specificity, anti-CCP (94%) was the highest and was comparable to that of CXCL13 (83%) and RF (83%). Conclusions: The sensitivity of CXCL13 was higher than that of anti-CCP antibodies for determining RA patients but specificity for CXCL13 was less. With its outcomes, CXCL13 can play an additive role in establishing the diagnosis of RA.