A 40-year-old woman presents with progressive proximal muscle weakness, a heliotrope rash, and Gottron papules. Muscle biopsy shows perifascicular atrophy. The autoantibody most strongly associated with this condition is:

• A Anti-Mi-2 ✓
• B Anti-Jo-1 (antisynthetase)
• C Anti-SRP
• D Anti-TIF1-gamma

Explanation

The clinical picture (heliotrope rash, Gottron papules, proximal muscle weakness) is classic dermatomyositis. Anti-Mi-2 antibodies are highly specific for dermatomyositis. Anti-Jo-1 is associated with antisynthetase syndrome. Anti-SRP is seen in immune-mediated necrotizing myopathy. Anti-TIF1-gamma is associated with cancer-associated dermatomyositis.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.