CASE OF THE MONTH - AMYLOIDOSIS CAUSING A PROGRESSIVE MYOPATHY

A 62-year-old woman developed profound weakness secondary to a progres sive myopathy associated with primary systemic amyloidosis. The charac teristic apple-green birefringent amyloid deposits were demonstrated s urrounding individual muscle fibers in Congo red stained sections. Ele ctron microscopy demonstrated amyloid filaments in close apposition to muscle fibers exhibiting excessive corrugations of the sarcolemmal me mbrane. The pathological features of progressive amyloid myopathy asso ciated with primary systemic amyloidosis are distinct from the intrace llular amyloid deposits characteristic of sporadic inclusion body myos itis and inherited inclusion body myopathy. (C) 1995 John Wiley and So ns, Inc.