Síndrome antisintetasa. Informe de un caso

Introduction: The antisynthetase syndrome has been described in adults with an average age of 45 to 60 years, but it can affect children, predominantly females. Its features include myositis, polymyositis, interstitial lung disease and the presence of aminoacyl tRNA antibodies of which the Anti Jo-1 is the most common. Case Report: A 6 year old girl had a two year history of fever, arthritis syndrome, progressive muscle weakness, Raynaud’s phenomenon, myalgia, malar heliotrope rash, Gottron’s papules and “mechanic hands”, tachypnea, finger clubbing. The patient was oxygen-dependent. X-ray and computerized axial tomography showed images suggestive of lung fibrosis. She had elevated creatine: 4530 IU/mL, and positive Jo-1 antibody. There was a myopathic electromyography pattern. A muscle biopsy was compatible with polymyositis. Juvenile dermatomyositis with anti-synthetase syndrome was diagnosed. She was treated with methylprednisolone, prednisone, intravenous human immunoglobulin and cyclophosphamide. During the first year of treatment her muscle strength was recovered, fever and skin lesions disappeared, respiratory function became normal and there was no need for oxygen. Discussion. The antisynthetase syndrome includes polymyositis and dermatomyositis, interstitial lung disease, polyarthritis, Raynaud’s phenomenon, “mechanic hands” and the presence of serum anti-synthetase antibodies. Treatment should be comprehensive and holistic, in order to restore lung capacity, prevent progression of damage and improve life quality.