title: Muscular amyloid angiopathy with amyloidgenic transthyretin Ser50Ile and Tyr114Cys.
abstract: Among patients with familial amyloid polyneuropathy (FAP), those with transthyretin Val30Met mainly show distally predominant weakness and atrophy, whereas some FAP patients, including those with transthyretin Ser50Ile and Tyr114Cys, show muscle weakness and atrophy that is dominant proximally, simulating myopathy. To clarify the cause of proximally dominant muscular atrophy in patients with FAP transthyretin Ser50Ile and Tyr114Cys, we investigated the distinctive features of muscle specimens of patients with FAP, 3 of who had Val30Met, 2 Ser50Ile, and 2 Tyr114Cys transthyretin. All specimens showed transthyretin amyloid around blood vessels and perimysium, and neurogenic denervation patterns. The amount of amyloid around the vessels was much greater in patients with FAP Ser50Ile and Tyr114Cys than in Val30Met patients. Muscular amyloid angiopathy may contribute to motor nerve injury that, in turn, may lead to amyotropic changes in patients with FAP Ser50Ile and Tyr114Cys.
authors.affiliation: Department of Neurology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Yamashita
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ando
authors.forename: Shoichi
authors.initials: S
authors.lastname: Katsuragi
authors.forename: Masaaki
authors.initials: M
authors.lastname: Nakamura
authors.forename: Konen
authors.initials: K
authors.lastname: Obayashi
authors.forename: Katsuki
authors.initials: K
authors.lastname: Haraoka
authors.forename: Mitsuharu
authors.initials: M
authors.lastname: Ueda
authors.forename: Sun
authors.initials: S
authors.lastname: Xuguo
authors.forename: Sadahisa
authors.initials: S
authors.lastname: Okamoto
authors.forename: Makoto
authors.initials: M
authors.lastname: Uchino
mesh_terms: D000328:Adult; D028227:Amyloid Neuropathies, Familial / Q000235:genetics* / Q000473:pathology*; D001706:Biopsy; D002196:Capillaries / Q000648:ultrastructure; D005260:Female; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000098:blood supply / Q000473:pathology / Q000648:ultrastructure; D009133:Muscular Atrophy / Q000235:genetics* / Q000473:pathology*; D009416:Nerve Regeneration; D017354:Point Mutation; D011228:Prealbumin / Q000235:genetics*
chemical_list: D011228:Prealbumin