title: Amyloid polyneuropathy caused by wild-type transthyretin.
abstract: BACKGROUND
  Amyloidosis derived from transthyretin (TTR) molecules is typically caused by mutations of the TTR gene.
  
  
  METHODS
  We describe an elderly patient with a severe length-dependent polyneuropathy that unexpectedly proved to be caused by wild-type transthyretin amyloidosis.
  
  
  RESULTS
  The diagnosis was made by muscle biopsy, because no amyloid deposits were found in the biopsied nerve segment. Most cases of wild-type transthyretin amyloidosis occur in elderly patients with cardiomyopathy, but a few cases of polyneuropathy have been reported.
  
  
  CONCLUSIONS
  This entity is especially noteworthy in light of emerging treatment options for hereditary transthyretin amyloidosis, which are likely to also be beneficial in wild-type disease.
authors.affiliation: Department of Neurology, Kaiser Permanente Medical Center, San Rafael, California, USA.
authors.forename: Lynda
authors.initials: L
authors.lastname: Lam
authors.affiliation: Department of Pathology, University of California, San Francisco, California, USA.
authors.forename: Marta
authors.initials: M
authors.lastname: Margeta
authors.affiliation: Department of Neurology, University of California, San Francisco, California, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Layzer
mesh_terms: D000369:Aged, 80 and over; D000682:Amyloid / Q000378:metabolism; D017772:Amyloid Neuropathies / Q000235:genetics* / Q000473:pathology*; D005260:Female; D006801:Humans; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D011228:Prealbumin / Q000235:genetics*
chemical_list: D000682:Amyloid; D011228:Prealbumin
keywords: amyloid polyneuropathy; nerve biopsy; senile systemic amyloidosis; sensorimotor polyneuropathy; wild-type transthyretin amyloidosis