Antisynthetase Syndrome Diagnosis and Management

Introduction to Antisynthetase Syndrome

The American College of Rheumatology suggests that the presence of anti-Jo1 antibodies indicates antisynthetase syndrome, a autoimmune disease characterized by myositis, interstitial lung disease (ILD), arthritis, Raynaud's phenomenon, mechanic's hands, and fever 1
The Mayo Clinic recommends that anti-Jo1 antibodies are directed against histidyl-tRNA synthetase, a cytoplasmic enzyme involved in protein synthesis, and are the most common antisynthetase autoantibodies 1

The American Thoracic Society recommends that high-resolution chest CT should be performed in all patients with positive anti-Jo1 antibodies to evaluate ILD patterns 3
The European Respiratory Society suggests that pulmonary function tests typically reveal a restrictive pattern with low diffusion capacity 2
The American College of Rheumatology recommends that a complete autoantibody panel should be ordered in all patients with suspected inflammatory myopathy, as approximately 80% will have at least one detectable antibody 2

The presence of anti-Jo1 antibodies defines antisynthetase syndrome, which includes six main characteristics: myositis, ILD, arthritis, Raynaud's phenomenon, mechanic's hands, and fever 1, 2
The American College of Rheumatology reports that ILD is present in a significant proportion of patients and represents a major determinant of morbidity and mortality 3
The European League Against Rheumatism suggests that polyarthritis is a common feature, often seronegative (rheumatoid factor and anti-CCP negative) 1

The American Thoracic Society recommends that the control of interstitial alveolitis is crucial for long-term outcomes 3
The American College of Rheumatology suggests that high-dose corticosteroids represent the first-line treatment, and immunosuppressive drugs should be used in combination with corticosteroids as early as possible 1
The European League Against Rheumatism recommends that steroid-sparing agents, such as methotrexate, azathioprine, and mycophenolate mofetil, should be used in combination with corticosteroids 1