Anti-cyclic citrullinated peptide antibodies in primary Sjögren syndrome may be associated with non-erosive synovitis

Fabiola Atzeni¹ , Piercarlo Sarzi-Puttini¹ , Nicola Lama² , Eleonora Bonacci³ , Francesca Bobbio-Pallavicini³ , Carlomaurizio Montecucco³ and Roberto Caporali³

¹Rheumatology Unit, L. Sacco Hospital, University of Milan, Via G.B. Grassi 74, 20127 Milan, Italy

²Department of Medicine and Public Health, Second University of Naples, Via L Armanni 75, 80139 Naples, Italy

³University of Pavia, IRCCS Policlinico S. Matteo, Piazzale Golgi 12, 27100 Pavia, Italy

author email corresponding author email

Arthritis Research & Therapy 2008, 10:R51doi:10.1186/ar2420


Published:	7 May 2008

Abstract

Introduction

The purpose of this study was to investigate the prevalence of cyclic citrullinated peptide antibodies (anti-CCP) in patients with primary Sjögren syndrome (pSS) and its correlation with clinical and laboratory data.

Methods

We analysed the clinical and serological data of 155 consecutive patients with pSS. Among these, 14 were excluded due to fulfillment of American College of Rheumatology criteria for rheumatoid arthritis (RA). So, 141 patients (27 males and 114 females; mean age 48 years, range 39 to 60) were clinically assessed for the presence of synovitis (objective swelling of one or more joints) and extra-glandular involvement. The anti-CCP antibodies were tested using a commercially available second-generation enzyme-linked immunosorbent assay. IgM rheumatoid factor (RF) was determined by nephelometry.

Results

Fourteen patients (9.9%) had moderate to high levels of anti-CCP, and 94 (66.7%) were positive for RF. Eighty-one (57.4%) showed extra-glandular involvement, and 44 (31.2%) had synovitis without any radiographic sign of erosion. There was a close correlation between the presence of anti-CCP and synovitis (P < 0.001) but no association between anti-CCP and extra-glandular involvement (P = 0.77). Multivariate analysis confirmed the association between anti-CCP and an increased prevalence of synovitis (prevalence odds ratio for positive versus negative anti-CCP status 7.611, 95% confidence interval 1.475 to 74.870; P = 0.010).

Conclusion

Only a minority of patients with pSS are anti-CCP-positive, which seems to be closely associated with the prevalence of synovitis. Anti-CCP positivity in patients with pSS therefore may be a predictor of future progress to RA or an expression of the inflammatory process of synovial tissue.