Analysis Of The Relationship Between Serum Sialic Acid And Rheumatoid Arthritis

Objective:To assay and compare the serum level of sialic aicd(SA)in patients with rheumatoid arthritis(RA)and the control group,then to analyze the relationship between it and RA related indexes,both in laboratory and in clinic.And to investigate the possible mechanism of SA in the nosogenesis of RA.Subjects and Methods:A total of 120 patients with RA and 60 healthy contorls were entrolled.Comparing the serum level of SA between these two groups by enzymic method,and analyzing the relationship in RA patients between SA and erythtocyte sedimentation rate(ESR)?reactive protein(CRP),rheumatoid factor(RF),anti-cyclic citrulline protein antibodies,course,time of therapy,tender joint count(TJC),swollen joint count(SJC),visual analogue scale(VAS)and disease activity score(DAS-28).Statistical analysis was performed using Student's test,Chi-square test and Pearson correlation test.Results:1.The serum level of sialic acid in RA group(864.05±167.70)is obviously higher than the control group(570.99±67.37),and the difference is significant(P<0.05).2.The relationships between serum level of sialic acid in RA patients with their CRP,ESR,RF,anti-CCP antibody are all positive related,but only the relationships of CRP and ESR are significantly different(r=0.53,P=0.00;r=0.52,P=0.00;r=0.06,P=0.55;r=0.01,P=0.89,relatively).3.The relationships between serum level of sialic acid in RA patients with their clinical indexes,as age,TJC,SJC,DAS-28(CRP),DAS-28(ESR)and Sharp score are both positive related(r=0.07,P=0.43;r=0.32,P=0.00;r=0.22,P=0.02;r=0.47,P=0.00;r=0.47,P=0.00;r=0.13,P=0.58,relatively),but only the relationships with TJC,SJC,DAS-28(CRP),DAS-28(ESR)are significantly different(P<0.05).The relationships between patients' sialic acid with course and time of therapy are negative related(r=-0.09,P=0.31;r=-0.06,P=0.51,relatively),which is no significant difference(P>0.05).Conclusion:1.The disease activity of RA is related with its serum level of siaclic acid.2.The deleted sialic acid at the end of glycosylated terminal in proteins may be related with the morbidity of RA.3.The deleted sialic acid of the glycan structure in immunoglobulin may induce the auto-immune response,which may cause synovitis.4.The combined usage of Ig G0,Siglec-1,RF and anti-CCP antibody could help to diagnose RA early and evaluate the treatment.5.The serum level of sialic acid could be used as a clinical index to monitor the disease activity and help to make a treatment plan.