Abstract

*Dounya Bounid MD, Mohammed Oujidi MD, Soukaina Erradi MSc, Hind Trii MSc and Brahim Admou MD

ABSTRACT

Introduction: Anti-SSA / Ro antibodies are frequently encountered during systemic lupus erythematosus (LES) and Gougerot-Sjögren syndrome (SGS), they can however be associated with other autoimmune or non-auto- immune, which raises the question of their specificity and their interest in clinical practice. The aim of our study was to determine the clinical significance of anti-SSA antibodies’s positivity. Patients and Methods: Our study focused on 87 patients with anti SSA / Ro antibodies positives, collected from cases of anti-ENA (Extractible nuclear antigens) antibodies, identified by an immuno-dot technique (D-teck, Bluediver, Aesku), after an AAN screening step (anti-nuclear antibodies) by indirect immunofluorescence (Hep-2, kallestad, Bio-rad). The identification of anti-ENA antibodies consisted in the characterization of the SSA Ro52 and Ro 60 subtypes as well as other autoantibody specificities (SSB, DNA, nucleosomes, histones, Sm, Sm/RNP, RNP, Jo-1, Scl70, PM/Scl) and anti-CCP detected by ELISA technique (EIA, Bio-rad). The result of these different autoantibodies was compared with the clinical and biological data of the patients. Results: The mean age of our patients was 46,64 ± 13,38 years (range: 21-76), with a female predominance (Sex-ratio M/F = 0,2). Among the 87 cases of anti-SSA / Ro positive selected, 35 (40%) of them had a SLE, 14 (16%) had rheumatoid arthritis, 12 (13,8%) a systemic scleroderma, 11 (12,6%) SGS including 8 cases (9,2%) of primary SGS and 3 cases (3.4%) of secondary SGS, 4 (5%) mixed connectivitis, 2 cases (2,3%) dermatomyositis and 1 case (1,15%) a polymyositis. In 9.2% of cases (n=8), anti-SSA antibodies were found in non-autoimmune diseases. Anti-SSA / Ro 60 were significantly associated with SLE (p=0,01), RA (p=0,04), mixed connectivitis (p=0,002) and dermatomyositis (p=0,04). No significant difference was noted between these antibodies or their subtypes, neither with the primary or secondary SGS. Conclusion: The presence of anti-SSA antibodies was more frequently encountered during SLE, RA, ScS and SGS, but were also found in non-autoimmune pathologies. These results underline the importance of a careful interpretation of these autoantibodies in order to establish with precision their real clinical significance and to help better therapeutic management of patients.