A 38-year-old woman presents with progressive proximal muscle weakness, interstitial lung disease, mechanic's hands, and anti-Jo-1 antibody positivity. What is the most likely diagnosis?
- A Dermatomyositis
- B Polymyositis
- C Antisynthetase syndrome ✓
- D Inclusion body myositis
Correct answer: C. Antisynthetase syndrome
Explanation
Antisynthetase syndrome is characterized by anti-aminoacyl-tRNA synthetase antibodies (most commonly anti-Jo-1), interstitial lung disease, inflammatory myopathy, mechanic's hands, Raynaud phenomenon, and arthritis. Dermatomyositis features heliotrope rash and Gottron papules. Polymyositis lacks the ILD and specific autoantibody. IBM is asymmetric and refractory to treatment.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.