Tongue atrophy and fasciculations in transthyretin familial amyloid neuropathy

OBJECTIVE: Macroglossia is a well-known feature of amyloidosis; however, tongue atrophy and fasciculations are rarely seen and can lead to the misdiagnosis of amyotrophic lateral sclerosis (ALS). METHODS: We identified 2 unrelated patients with atypical features of tongue atrophy and fasciculations in the setting of a severe neuropathy. RESULTS: Both patients were confirmed to have transthyretin-related familial amyloid polyneuropathy (TTR-FAP) by genetic testing. CONCLUSIONS: TTR-FAP should be considered as a possible mimicker of ALS when tongue atrophy and fasciculations are seen in the setting of a severely progressive polyneuropathy. Other atypical mimickers of ALS include polyglucosan body disease, hexosaminidase A deficiency, multisystem proteinopathy, and Allgrove syndrome.