title: Progressive carotid artery stenosis with a novel tRNA phenylalanine mitochondrial DNA mutation.
abstract: Mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) is a distinct clinical syndrome caused by mutations in the mitochondrial DNA. The pathogenesis of stroke-like episodes remains unknown but major vessels stenosis is not a cause of stroke-like episodes. We describe a novel heteroplasmic G617A transition in the mitochondrial transfer RNA phenylalanine gene in a patient with encephalomyopathy who presented with recurrent embolic ischemic strokes accompanied by transient occlusion of middle cerebral, anterior cerebral and internal carotid arteries. These ischemic strokes were presumed to be artery-to artery embolisms associated with carotid artery stenosis. Single muscle fiber analysis revealed the pathogenicity of the mutation although its causative role on carotid artery stenosis remains to be elucidated. This case expands phenotypic spectrum of mitochondrial disorders in terms of macroangiopathy, but macroangiopathy-related ischemic strokes should be distinguished from classic stroke-like episodes of MELAS that are speculated to be microangioapthy-related or non-ischemic neurovascular events.
authors.affiliation: Department of Neurology, School of Medicine, Kitasato University, Kanagawa, Japan. takahiro@med.kitasato-u.ac.jp
authors.forename: Takahiro
authors.initials: T
authors.lastname: Iizuka
authors.forename: Yu-ichi
authors.initials: Y
authors.lastname: Goto
authors.forename: Saori
authors.initials: S
authors.lastname: Miyakawa
authors.forename: Mayumi
authors.initials: M
authors.lastname: Sato
authors.forename: Zhaoxia
authors.initials: Z
authors.lastname: Wang
authors.forename: Kosuke
authors.initials: K
authors.lastname: Suzuki
authors.forename: Junichi
authors.initials: J
authors.lastname: Hamada
authors.forename: Akira
authors.initials: A
authors.lastname: Kurata
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Sakai
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology; D002339:Carotid Arteries / Q000000981:diagnostic imaging; D016893:Carotid Stenosis / Q000235:genetics* / Q000473:pathology; D002533:Cerebral Angiography; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000235:genetics*; D050259:Genes, Mitochondrial; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D017237:Mitochondrial Encephalomyopathies / Q000235:genetics* / Q000473:pathology; D018482:Muscle, Skeletal / Q000473:pathology; D020125:Mutation, Missense; D009690:Nucleic Acid Conformation; D012360:RNA, Transfer, Phe / Q000737:chemistry / Q000235:genetics*; D020521:Stroke / Q000235:genetics / Q000473:pathology
chemical_list: D004272:DNA, Mitochondrial; D012360:RNA, Transfer, Phe