Transthyretin amyloidosis (serine 44) with headache, hearing loss, and peripheral neuropathy.

A 32-year-old man of Irish descent presented with severe progressive headache and sensorineural hearing loss. MRI/magnetic resonance angiography head scans were normal. A length-dependent sensorimotor peripheral neuropathy with autonomic dysfunction predated these symptoms. Systemic organ involvement and transthyretin (TTR) amyloid immunostaining of bone marrow and fat aspirate were documented. Direct DNA sequencing revealed both the normal TTT (phenylalanine) and a new variant TCT (serine) at position 44 of the TTR gene. This case expands the genotypic and phenotypic variability within TTR amyloidosis.