A 45-year-old woman has fever, polyarthritis, interstitial lung disease and hyperkeratotic fissured lesions on the radial sides of her index fingers and thumbs. Which autoantibody best explains this constellation?

• A Anti-Ku
• B Anti-Jo-1 (anti-histidyl tRNA synthetase) ✓
• C Anti-Mi-2
• D Anti-fibrillarin (U3 RNP)

Explanation

Mechanic's hands, hyperkeratotic fissuring of the radial digits, together with fever, arthritis and interstitial lung disease define the antisynthetase syndrome, most commonly associated with anti-Jo-1. Anti-Mi-2 marks classic dermatomyositis with prominent cutaneous disease and good treatment response, anti-Ku marks overlap myositis with sclerosis, and anti-fibrillarin correlates with diffuse systemic sclerosis and pulmonary hypertension.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.