Clinical significance of serum B cell chemokine (CXCL13) in early rheumatoid arthritis patients

Background

The diagnosis of early rheumatoid arthritis (RA) is challenging. B-cell chemokine (CXCL13) plays a critical role in the disease pathogenesis.

Aim of the work

To assess the diagnostic value of serum CXCL13 in early RA and compare it with rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies.

Patients and methods

The study included 60 RA patients; 30 early, 30 established RA and 30 healthy controls. The modified health assessment questionnaire (MHAQ), modified Sharp-van der Heijde score (MSS) and disease activity score (DAS28) were assessed in RA patients. RF, anti-CCP and serum level of CXCL13 were measured.

Results

Patients had a mean age of 39?±?7.4?years and disease duration of 4.4?±?5.7?years; they were 46 females and 12 males (F:M 3.8:1). Serum CXCL13 was significantly higher in early (191.7?±?74.4?pg/ml) compared to established (136.4?±?79?pg/ml) RA (p?=?0.007) which were not observed with RF and anti-CCP; both were higher than in control (30.4?±?13.5?pg/ml) (p?<?0.001). In early RA, the frequencies of CXCL13, RF and anti-CCP positivity were 90%, 73.3% and 56.7% while in the established cases the frequencies were 36.7%, 66.7% and 63.3% respectively. CXCL13 significantly correlated with DAS28 (early: 0.49, p?=?0.006; established: r?=?0.38, p?=?0.04) but not with MHAQ or MSS. The CXCL13 significantly correlated with both the RF and anti-CCP in both early and established cases (p?<?0.001).

Conclusion

CXCL13 is an important for the diagnosis of early RA with a superior diagnostic performance compared to RF and anti-CCP. It may also be considered a potential biomarker of disease activity.