A 35-year-old woman presents with symmetric proximal muscle difficulty (difficulty climbing stairs and rising from a chair) for 2 months, Gottron papules over the knuckles, and a heliotrope rash. CK is 2800 U/L. Anti-Jo-1 antibody is positive. What is the most likely diagnosis?

• A Systemic lupus erythematosus
• B Drug-induced myopathy
• C Polymyositis
• D Dermatomyositis ✓

Explanation

The heliotrope rash and Gottron papules are pathognomonic for dermatomyositis. Anti-Jo-1 is associated with antisynthetism syndrome in dermatomyositis or polymyositis, characterized by interstitial lung disease, Raynaud phenomenon, mechanic hands, and arthritis. Polymyositis lacks the characteristic skin findings.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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