Patients with seronegative RA have more inflammatory activity compared with patients with seropositive RA in an inception cohort of DMARD-naïve patients classified according to the 2010 ACR/EULAR criteria

Ann Rheum Dis. 2017 Feb;76(2):341-345. doi: 10.1136/annrheumdis-2015-208873. Epub 2016 Apr 19.


Objectives: To compare the presentation of seropositive and seronegative early rheumatoid arthritis (RA) in disease-modifying antirheumatic drug (DMARD)-naïve patients classified according to the 2010 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) criteria.

Methods: All patients had symptom duration from first swollen joint <2 years and were DMARD naïve with an indication for DMARD treatment. Patients were stratified as seropositive (positive rheumatoid factor (RF)+ and/or anticitrullinated peptide antibody (ACPA)+) or seronegative (RF- and ACPA-), and disease characteristics were compared between groups.

Results: A total of 234 patients were included, and 36 (15.4%) were seronegative. Ultrasonography (US) scores for joints (median 55 vs 25, p<0.001) and tendons (median 3 vs 0, p<0.001), number of swollen joints (median 17 vs 8, p<0.001), disease activity score (DAS; mean 3.9 vs 3.4, p=0.03) and physician global assessment (mean 49.1 vs 38.9, p=0.006) were significantly higher in seronegative patients compared with seropositive. Total van der Heijde-modified Sharp score, Richie Articular Index and patient-reported outcome measures were similar between groups.

Conclusions: Seronegative patients had higher levels of inflammation, assessed both clinically and by US, than seropositive patients. These differences may reflect the high number of involved joints required for seronegative patients to fulfil the 2010 ACR/EULAR classification criteria for RA.

Trial registration number: NCT01205854; Pre-results.

Keywords: Ant-CCP; Early Rheumatoid Arthritis; Rheumatoid Arthritis; Rheumatoid Factor.

MeSH terms

  • Adult
  • Aged
  • Antirheumatic Agents / therapeutic use
  • Arthritis, Rheumatoid / diagnostic imaging
  • Arthritis, Rheumatoid / drug therapy
  • Arthritis, Rheumatoid / immunology*
  • Arthritis, Rheumatoid / physiopathology
  • Autoantibodies / immunology*
  • Case-Control Studies
  • Foot Joints / diagnostic imaging
  • Foot Joints / physiopathology
  • Hand Joints / diagnostic imaging
  • Hand Joints / physiopathology
  • Humans
  • Male
  • Middle Aged
  • Peptides, Cyclic / immunology*
  • Rheumatoid Factor / immunology*
  • Severity of Illness Index
  • Ultrasonography
  • Ultrasonography, Doppler


  • Antirheumatic Agents
  • Autoantibodies
  • Peptides, Cyclic
  • cyclic citrullinated peptide
  • Rheumatoid Factor

Associated data