ABSTRACT
Objective To investigate the serum level of calcium-binding protein A9(S100A9)in patients with rheumatoid arthritis and explore its potential clinical significance. Methods The serum level of S100A9 was measured by ELISA in 79 rheumatoid arthritis (RA) patients and 20 healthy controls (HC). The correlation of S100A9 level and relevant clinical parameters were analyzed. Results The serum level of S100A9 was significantly increase in RA patients than those in HC. The serum level of S100A9 was higher in high disease activity than that in moderate and low disease activity in the RA group. There was a positive correlation in serum S100A9 level and DAS28 score,Rheumatoid factor,tender joint count and swollen joint count. Conclusion The serum level of S100A9 increases in RA patients and correlates with RA activity.