Transthyretin Variant Amyloidosis with a TTR A97D (p.A117D) Mutation Manifesting Remarkable Asymmetric Neuropathy

We herein report a 68-year-old Japanese man with sporadic variant transthyretin (ATTRv) amyloidosis harboring the novel variant A97D (p.A117D) in TTR. He had slow development of asymmetric neuropathy, unintentional weight loss, mild autonomic failure and mild cardiomyopathy. TTR amyloid deposition on the gastric duodenal mucosa was detected. In silico analyses predicted that TTR A97D (p.A117D) altered the structure and function of the TTR protein. ATTRv amyloidosis is often difficult to diagnose in non-endemic regions due to its diverse phenotypes, such as atypical peripheral nerve involvement and a rare family history.