Pathological analysis of individuals at risk of rheumatoid arthritis -Overview-

Abstract

European League Against Rheumatism（EULAR）describes the situation before the onset of RA as follows: ①“Individual at risk on the basis of genetic and environmental risk factors with no identifiable laboratory abnormalities and no symptoms or signs of inflammatory arthritis”, ②“Individual at risk of RA on the basis of laboratory abnormalities（eg, ACPA, RF positivity with no symptoms or signs of inflammatory arthritis”, ③“Individual at risk on the basis of symptoms of inflammatory arthritis（eg, arthralgia/morning stiffness）but no clinical or imaging evidence of synovitis”, ④“Individuals with synovitis on imaging but no clinically apparent inflammatory arthritis”, ⑤“Individual with clinically apparent inflammatory arthritis not yet fulfilling classification criteria for RA”. Thus, EULAR proposes to express these with“Pre-RA”, “Pre-clinical RA”, “Inflammatory arthralgia”, “Autoantibody-positive arthralgia”, and“Undifferentiated arthritis”. Considering the “window of opportunity” and “treat-to-target” in RA treatment, it is necessary to grasp the pathological conditions before the onset of RA as accurately as possible and predict the “risk of developing RA” in each individual as accurately as possible. Accordingly, these are the extremely important research themes that is directly linked to the introduction of（ultra）early treatment toward inflammatory arthritis patients in the near future.