Background/Purpose: Idiopathic inflammatory myopathies (IIM) are a group of acquired diseases, characterized by immunoflogistic processes primarily involving the skeletal muscle. Myositis-associated antibodies are frequently detected in IIM patients’ sera, particularly in those with overlap syndromes; more specifically, the clinical relevance of anti-Ro/SSA has not been fully elucidated. Aim of this study is to establish the prevalence of Ro/SSA in a single centre cohort of patient with IIM followed in our Rheumatology Unit and to investigate their influence on the IIM clinical expression.

Methods: Clinical charts of patients diagnosed as IIM according with Bohan e Peter criteria and followed between 1974 and 2012 were retrospectively examined. Antibodies antiRo/SSA were determined by counterimmunoelectrophoresis. Epidemiological, clinical, laboratory, instrumental and histological features of the patients were collected.

Results: a total of two hundred and forty six patients affected by IIM were identified; 21 (8.6%) were positive for  anti-Ro/SSA antibodies. The anti-Ro/SSA positivity was associated with xerostomia 12/21 (p<0.001) and xerophthalmia 14/21 (p<0.001). A biopsy of accessory salivary glands was performed in 10 patients resulting positive in 9/10; moreover a strict association with an overlapping Sjögren’s Syndrome (IIM/SS) diagnosed according to AECG criteria was found in 11/21 cases (p=0.000). The anti-Ro/SSA positivity was also associated with patients’ reported “dysphagia” in IIM patients (p=0.035) and with the use of intravenous immunoglobulins (p<0.001). By contrast, no differences were found in the prevalence of abnormalities at the oesophagus x-ray examination between anti-Ro/SSA positive and negative patients. No differences were also found between the two groups regarding: sex, age, subset of disease (polymyositis, dermatomyositis, inclusion body myositis), muscular or cutaneous involvement, pulmonary fibrosis, incidence of neoplasm, creatinine phosphokinase or other muscular necrosis enzyme, association with anti-Jo-1 autoantibodies.

Conclusion: In IIM patients the positivity for the anti-Ro/SSA antibodies is associated, as attended, with secondary SS. The increased prevalence of subjective dysphagia reported by patients positive for anti-Ro/SSA might be partially related to the oral dryness which may worsen the IIM oesophageal involvement.

Further prospective studies are required to elucidate the pathogenic mechanisms of dysphagia in IIM patients and the therapeutic implication of our findings.

---

« Back to 2013 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/influence-of-anti-rossa-autoantibodies-on-cinical-characteristic-of-a-cohort-of-myositis-patients/