The significance of serum 14-3-3η level in rheumatoid arthritis patients

Background: RA is a systemic inflammatory condition characterized by chronic arthritis and often associated with irreversible joint damage.

Objectives: To assess the significance of serum level of 14-3-3η in RA and its association with clinical and serological features of the disease.

Methods: This is a case-control study done on 80 participants. They were divided into 2 groups. Group 1: 40 rheumatoid arthritis patients compared to group 2: 40 healthy participants matched for age and sex. Laboratory investigations including complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) rheumatoid factor (RF), anti-citrullinated peptide antibodies (ACPAs), and serum 14-3-3η were done to all participants. Radiological examination in the form of plain X-ray for hands and feet was done to all patients.

Results: Serum levels of 14-3-3η were significantly higher in RA patients compared to the control group (p < 0.001). Serum 14-3-3η was the only predictor of high Larsen's score (p = 0.013) on using linear regression analysis. Serum 14-3-3η can predict RA in healthy controls in univariate (p = 0.001) and multivariate (p = 0.004) analyses. The receiver operating characteristic (ROC) curve of 14-3-3η was constructed for discrimination between RA and control subjects. The best cut-off value was 61.9 ng/mL, with fair AUC (0.773, p < 0.001), 95% CI (0.656-0.889), and the sensitivity and specificity of 14-3-3η for RA diagnosis as 65% and 95% respectively. Also, we constructed ROC curves for RF, ACPA, 14-3-3η, and their combinations; we found that the highest test sensitivity of 95.7% appeared on adding the 3 markers together, and the highest test specificity of 100% was detected on adding RF to ACPA, 14-3-3η to ACPA or the 3 molecules together.

Conclusion: 14-3-3η could be a valuable marker for the diagnosis of RA patients and it may have prognostic value. Key Points • 14-3-3η is a valuable marker for the diagnosis of RA patients. • 14-3-3η reflects disease severity and joint damage in RA patients.