Rheumatoid factor. Its association with inflammatory answer markers

Abstract

The rheumatoid factor is a well-known autoimmunity biomarker, related to several chronic inflammatory diseases, mainly to Rheumatoid Arthritis. The explanation of its pathogenic role and its predictive-developing value can be helped by knowing its relation with other markers of inflammatory answer. To analyze the association of the rheumatoid factor with seric markers C reactive, C3 and C4 complement proteins, IgG, IgM, and IgA, we carried out a transversal study with quantitative inmunoturbidimetric determination of those variables in a sample formed by 83 healthy control individuals and 44 patients carrying diseases related with seric increase of the rheumatoid factor. To analyze the results we used the statistics program SSPS, version 16,0. The analysis of lineal correlation did not show significant association (p>0, 05) of the rheumatoid factor to the rest of the variables in healthy controls, while it was inversely associated to complete C4 in patients without rheumatoid arthritis (r=-0,475; p=0,014) and in those with increased rheumatoid factor (>20 UI/ml) (de Spearman´s Rho =-0,472; p=0,048) ; it also was directly associated to reactive C protein in patients with rheumatoid arthritis clinically exacerbated (Spearman´s Rho =0,598; p=0,014), and to C3 complement in patients with normal rheumatoid factor (<20U/ml) (r=0,406; p=0,040) .
These results show the association of the rheumatoid factor with an acute inflammatory answer in pathologic conditions, the possible link of this marker with seric complement consumption, via classical activated, in patients with increased levels of it, and a possible role of this marker as acute phase reactant.