title: The features of the synovium in early rheumatoid arthritis according to the 2010 ACR/EULAR classification criteria.
abstract: OBJECTIVE
  It has been shown in early arthritis cohorts that the 2010 ACR/EULAR criteria for rheumatoid arthritis (RA) enable an earlier diagnosis, perhaps at the cost of a somewhat more heterogeneous patient population. We describe the features of synovial inflammation in RA patients classified according to these new criteria.
  
  
  METHODS
  At baseline, synovial tissue biopsy samples were obtained from disease-modifying antirheumatic drug (DMARD)-naïve early RA patients (clinical signs and symptoms <1 year). Synovial tissue was analyzed for cell infiltration, vascularity, and expression of adhesion molecules. Stained sections were evaluated by digital image analysis. Patients were classified according to the two different sets of classification criteria, autoantibody status, and outcome.
  
  
  RESULTS
  Synovial tissue of 69 RA patients according to 2010 ACR/EULAR criteria was analyzed: 56 patients who fulfilled the criteria for RA at baseline and 13 who were initially diagnosed as undifferentiated arthritis but fulfilled criteria for RA upon follow up. The synovium at baseline was infiltrated by plasma cells, macrophages, and T cells as well as other cells, and findings were comparable to those when patients were selected based on the 1987 ACR criteria for RA. There was no clear cut difference in the characteristics of the synovium between RA patients initially diagnosed as undifferentiated arthritis and those who already fulfilled classification criteria at baseline.
  
  
  CONCLUSIONS
  The features of synovial inflammation are similar when the 2010 ACR/EULAR classification criteria are used compared to the 1987 ACR criteria.
authors.affiliation: Division of Clinical Immunology and Rheumatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Marleen G H
authors.initials: MG
authors.lastname: van de Sande
authors.forename: Maria J H
authors.initials: MJ
authors.lastname: de Hair
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Schuller
authors.forename: Gijs P M
authors.initials: GP
authors.lastname: van de Sande
authors.forename: Carla A
authors.initials: CA
authors.lastname: Wijbrandts
authors.forename: Huib J
authors.initials: HJ
authors.lastname: Dinant
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Gerlag
authors.forename: Paul P
authors.initials: PP
authors.lastname: Tak
mesh_terms: D000569:Americas; D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D001323:Autoantibodies / Q000276:immunology; D015415:Biomarkers / Q000378:metabolism; D001808:Blood Vessels / Q000378:metabolism; D015331:Cohort Studies; D005060:Europe; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011379:Prognosis; D011446:Prospective Studies; D012952:Societies / Q000592:standards*; D013583:Synovial Membrane / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D013997:Time Factors
chemical_list: D001323:Autoantibodies; D015415:Biomarkers