Article Text

PDF
The role of the shared epitope in arthralgia with anti-cyclic citrullinated peptide antibodies (anti-CCP), and its effect on anti-CCP levels
  1. W H Bos1,
  2. J Ursum1,
  3. N de Vries2,
  4. G M Bartelds1,
  5. G J Wolbink1,3,
  6. M T Nurmohamed1,4,
  7. I E van der Horst-Bruinsma4,
  8. R J van de Stadt1,
  9. J B A Crusius4,
  10. P P Tak2,
  11. B A C Dijkmans1,4,
  12. D van Schaardenburg1,4
  1. 1
    Jan van Breemen Institute, Department of Rheumatology, Amsterdam, The Netherlands
  2. 2
    AMC/University of Amsterdam, Department of Clinical Immunology & Rheumatology, Department of Rheumatology, Amsterdam, The Netherlands
  3. 3
    Sanquin Research, Department of Rheumatology, Amsterdam, The Netherlands
  4. 4
    VU University Medical Center, Department of Rheumatology, Amsterdam, The Netherlands
  1. Dr D van Schaardenburg, Dr Jan van Breemen Straat 2, 1056 AB Amsterdam, The Netherlands; d.v.schaardenburg{at}janvanbreemen.nl

Abstract

Objectives: Patients presenting with both arthralgia and antibodies to cyclic citrullinated peptide (anti-CCP) have an increased risk of developing rheumatoid arthritis (RA). To further characterise this patient group and shed more light on its relationship with clinically manifest early arthritis and established RA, an immunogenetic and serological analysis was performed.

Methods: In a group of 111 patients with anti-CCP-positive arthralgia, anti-CCP levels and shared epitope (SE) status were determined. Data were compared with 125 and 128 patients with anti-CCP-positive early arthritis and established RA respectively.

Results: In patients with anti-CCP-positive arthralgia, the frequency of SE allele positivity is significantly lower when compared with anti-CCP-positive early arthritis and established RA (58% vs 80%, and 58% vs 92%, respectively, both p<0.001). Median anti-CCP levels were higher in the group of patients with SE-positive arthralgia compared with the group of patients with SE-negative arthralgia (p = 0.02). Median anti-CCP levels were similar in the groups of patients with SE-positive arthralgia and arthritis.

Conclusions: The lower frequency of SE positivity in patients with arthralgia compared with patients with RA indicates that, compared with patients who were SE positive, patients who were SE negative as a group go through a longer arthralgia phase, or alternatively have a lower risk for transition from anti-CCP positive arthralgia to RA. Furthermore, the present results suggest that in this early stage the effect of the SE on disease risk may be mediated through higher anti-CCP levels.

Statistics from Altmetric.com

Footnotes

  • Competing interests: None.

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.