Spinal multifocal amyloidosis derived from wild-type transthyretin.

Abstract Spinal amyloidosis can occur as a part of systemic amyloidosis or as localized amyloidomas. However, the exact pathogenesis of the spinal amyloidosis remains to be fully understood. Transthyretin (TTR) is an amyloidogenic protein causing two kinds of amyloid diseases. One is senile systemic amyloidosis (SSA), which is caused by wild-type (WT) TTR and primarily affects cardiac functions. The other type is familial amyloidosis, which is mainly induced by mutated TTR. We report here the first case of multifocal spinal TTR amyloidosis derived from WT TTR with radiculomyelopathy and destructive spondylosis. The data and clinical manifestations suggest that the patient may develop SSA. Clinical manifestations of TTR-related amyloidosis may vary more than we previously thought. In spinal amyloidosis, WT TTR is one of the candidate precursor proteins for the disease.