Erosive arthritis in a patient with amyloid arthropathy.

Amyloid arthropathy is said to be distinguished roentgenographically from rheumatoid arthritis by the absence of joint space narrowing and the absence of articular erosions. We present a patient with multiple myeloma with swelling, stiffness and firm synovial thickening of the wrists, metacarpophalangeal joints and proximal interphalangeal joints whose hand radiographs showed articular erosions of the carpal joints and ulnar styloid and joint space narrowing of the proximal interphalangeal joints and metacarpophalangeal joints. Synovial biopsy of the left wrist showed amyloid deposits with no inflammation. Previous reports of X-ray changes in amyloid arthropathy note preservation of joint spaces or widening. Erosions when noted are of non-articular bone rather than of the articular surface. This is the first case report of erosive articular disease in amyloid arthropathy.