The Diagnostic Significance of Serum Sclerostin in Early Detection of Rheumatoid Arthritis in Syrian Patients

Rheumatoid arthritis (RA) is associated with joint deformities and local bone erosions. Sclerostin is an inhibitor of the Wnt pathway and drives to reduce bone formation.

Our study aimed to compare the diagnostic significance of sclerostin with anti-CCP (anti-cyclic citrullinated peptide; normal level<20 IU/ml, and rheumatoid factor (RF; normal level<16 IU/ml) for the early diagnosis of rheumatoid arthritis in Syrian patients.

This study contained fifty-eight RA patients and thirty healthy individuals who were equally age- and sex-matched. Serum sclerostin and serum anti-CCP (IgG) levels were evaluated by using the enzyme-linked immunosorbent assay (ELISA). RA activity was assessed based on disease activity scores (DAS28).

Our results indicated that serum levels of sclerostin levels were higher in the RA group than in the healthy group (p<0.001). There was a positive correlation between serum sclerostin and DAS28-ESR (r=0.413, p=0.001). By ROC curve, the most optimal cut-off value of sclerostin was 249.69 pg/ml (AUC was 0.910 with 95% confidence interval (CI) values (0.852-0.969), sensitivity of 87.9%, and specificity of 93.3%) [Odds Ratio (OR) and P-value: 102, P< 0.0001]. In RA patients, the sensitivity and specificity of anti-CCP were 74.1% and 90%, and 70.6% and 86.6% of RF, respectively.

Increased serum sclerostin may aid as a new prognostic biomarker for evaluating the activity of RA. Sclerostin showed higher sensitivity and specificity than anti-CCP and RF-IgM antibodies. Therefore, sclerostin is a sensitive and specific biomarker for early diagnosis of rheumatoid arthritis.