E53 Anti-OJ synthetase syndrome: a pediatric case report

Abstract

Abstract Introduction The antisynthetase syndrome (ASS) is a connectivity with variable clinical expression. It is defined by the presence of anti-tRNA synthetase autoantibodies, associated with a clinical phenotype. It is an overlapping myositis associated with the presence of idiopathic inflammatory myopathy autoantibodies. Observation We report the case of an 11-year-old girl with no particular family history. The patient was diagnosed and treated as rheumatic fever 3 years ago and put on extencillin due to arthralgias of large right knee and hip joints with positive antistreptolysin O antibodies and history of repeated angina but without clinical improvement. The polyarthralgias progressed and became bilateral predominantly in the scapular and pelvic girdles associated with intense myalgias of three days before his admission leading to a motor deficit. A biological assessment was requested: creatine phosphokinase (CPK) = 1880UI/l; ASAT = 58UI/l; procalcitonin = 0.15; erythrocytesedimentation rate (ESR) was elevated. The immunological workup showed antibodies specific for myositis; antiRNA synthetase type OJ Positive. Results of immunological tests for other associated autoimmune diseases were (rheumatoid factor, anti-CyclicCitrullinated Peptide antibodies, anti SM and anti-Native DNA) negative. Electromyography showed no abnormalities. A muscle biopsy was not done. Chest CT scan showed no abnormalities. The patient was commenced on corticosteroid therapy at a dose of 1 mg/kg/day for 4–6 weeks then progressive weaning. Conclusion ASS is a complex and heterogeneous autoimmune connective disease. In the presence of extra-pulmonary signs and the positivity of the anti-tRNA synthetase antibody, the diagnosis is confirmed. The management often requires multidisciplinary approach.