Transthyretin Amyloidosis Presenting with Upper-Extremity Neuropathy and Paucity of Autonomic Impairment

We report a 73-year-old man with Val142Ile transthyretin (TTR) amyloidosis and an atypical clinical presentation of upper-extremity-predominant neuropathy without significant autonomic or cardiac involvement. TTR familial amyloid polyneuropathy commonly presents as length-dependent sensorimotor polyneuropathy with marked and early autonomic involvement. Multiple pathogenic mutations in TTR gene have been identified, of which Val50Met is commonly associated with TTR familial amyloid polyneuropathy, and Val142Ile is commonly associated with familial amyloid cardiomyopathy. Our patient is from a nonendemic region, without family history for amyloidosis. Predominant upper-extremity neuropathy, without significant cardiac or autonomic involvement, distinguishes this case from previously reported Val142Ile-mutated TTR amyloidosis.