Anti-alpha-fodrin antibodies in patients with Sjögren's syndrome secondary to rheumatoid arthritis

• Autor(a) principal: Nisihara,Renato
• Data de Publicação: 2016
• Outros Autores: Skare,Thelma L., Cenci,Elisa, Gabardo,Denise, Nass,Flavia, Utiyama,Shirley R. R.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Jornal Brasileiro de Patologia e Medicina Laboratorial (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1676-24442016000300137
• topic: Sjögren's syndrome; autoimmunity; autoantibodies; arthritis rheumatoid

ABSTRACT Introduction: The Sjögren's syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration. The currently most researched antibodies for its diagnosis are anti-La and anti-Ro, which, however, have low specificity in the case of SS secondary to rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The antibodies against alpha-fodrin (AF) have been proposed to diagnose SS. Objective: In the present study, we investigated the anti-AF antibody in a group of RA patients with and without secondary SS (sSS). Methods: Were studied 90 consecutive patients with RA (48.8% of them with SS), and samples of 45 healthy volunteers. Anti-AF immunoglobulin class G (IgG) and anti-AF immunoglobulin class A (IgA) were investigated by enzyme-linked immunosorbent assay (ELISA) and were considered positive when >15 U/ml. Demographic, clinical, and serological data were obtained from chart reviews. Results: Anti-AF IgA was positive in 46/90 (51.1%) of the RA sample and 3/45 (6.7%) of controls (p < 0.001); anti-AF IgG was found in 21/90 (23.3%) of RA patients and none of controls (p = 0.037). Neither IgA nor IgG anti-AF antibodies showed significant difference in patients with and without sSS. Conclusion: In our study, anti-AF IgA and anti-AF IgG neither alloweded diagnosis of sSS in RA patients, nor marked any special clinical or serological finding.