Current studies of biomarkers for the early diagnosis of rheumatoid arthritis

Abstract: Early treatment of rheumatoid arthritis (RA) with disease-modifying antirheumatic drugs will improve the outcome significantly. Early diagnosis of RA continues to be a challenge. The disease needs to be distinguished from other self-limiting arthritis and connective tissue disease. Currently available autoantibodies like rheumatoid factors and anticitrullinated cyclic peptide have limited sensitivity and specificity. RA, being a heterogeneous disease, with no unique or distinct defect that has been described, is less likely to have a single pathognomonic marker. There are defined predisposing genetic factors, cell characteristics, cytokine changes, autoantibodies, and products of disease process that have been demonstrated to distinguish rheumatoid from normal and other arthritis. Studies have demonstrated that combinations of factors allow for more specific RA diagnosis; however, when considerations are given to the factors separately, sensitivity increases at the cost of specificity. The present review briefly describes the value of some of the candidate factors and their combinations as diagnostic markers of early RA. Well-designed multicenter studies to evaluate these combinations using a scoring system are recommended for the development of precise and widely applicable biomarkers for early diagnosis of RA. Keywords: autoantibodies, combination, early RA, specificity