A 30-year-old woman with systemic lupus erythematosus has ulnar deviation and swan neck posturing of both hands. Radiographs show normal joint spaces with no erosions, and all deformities are fully passively correctable. The most likely diagnosis is:

• A Jaccoud arthropathy ✓
• B Rheumatoid arthritis with early erosive change
• C Psoriatic arthritis mutilans
• D Calcium pyrophosphate deposition arthropathy

Explanation

Jaccoud arthropathy of lupus produces reducible ulnar drift and swan neck deformities from ligamentous laxity and capsular stretching rather than cartilage destruction, so radiographs show no erosions and joint spaces are preserved. Rheumatoid arthritis is distinguished by marginal erosions and fixed deformity, which are absent here. The combination of correctability plus absent erosions is the discriminating feature.

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.