title: Mitochondrial encephalomyopathy: towards diagnosis. A case report.
abstract: Mitochondrial diseases may cause a wide range of central and peripheral nervous system disorders, as well as muscle disorders. The diagnostic workup routinely includes electrophysiological, morphological, neuroimaging and genetic studies. In some cases, the diagnosis may be ascertained only when mitochondrial DNA (mtDNA) examination in the muscle is performed. We report on a case of a 24-year-old woman, with a 7-year history of slowly progressive cerebellar syndrome and bilateral ptosis. Mitochondrial encephalomyopathy was suspected, based on the clinical picture and results of examinations, but the typical red ragged fibers were not found in the muscle biopsy. The results of molecular analysis of mtDNA showed a mtDNA deletion in the muscle and, on a level detectable only with polymerase chain reaction method, in blood leukocytes. This case emphasizes the important role of mtDNA studies in muscle in nonspecific multisystem mitochondrial disorders, even without clinical muscle involvement.
authors.affiliation: Department of Neurology, Medical University of Warsaw, Warsaw, Poland. Electronic address: mgawel@wum.edu.pl.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Gaweł
authors.affiliation: Department of Neurology, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Biruta
authors.initials: B
authors.lastname: Kierdaszuk
authors.affiliation: Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Tońska
authors.affiliation: Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Kaliszewska
authors.affiliation: Department of Neurology, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Justyna
authors.initials: J
authors.lastname: Kubiszewska
authors.affiliation: Department of Neurology, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Zygmunt
authors.initials: Z
authors.lastname: Jamrozik
authors.affiliation: Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland; Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Bartnik
authors.affiliation: Department of Neurology, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Hubert
authors.initials: H
authors.lastname: Kwieciński
authors.affiliation: Department of Neurology, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Kamińska
mesh_terms: D001259:Ataxia / Q000235:genetics / Q000503:physiopathology; D001483:Base Sequence; D001706:Biopsy; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000235:genetics*; D004568:Electrodiagnosis; D004569:Electroencephalography; D004576:Electromyography; D005260:Female; D005819:Genetic Markers; D006801:Humans; D008279:Magnetic Resonance Imaging; D017237:Mitochondrial Encephalomyopathies / Q000175:diagnosis* / Q000503:physiopathology; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology; D009431:Neural Conduction; D009460:Neurologic Examination; D016133:Polymerase Chain Reaction; D055815:Young Adult
chemical_list: D004272:DNA, Mitochondrial; D005819:Genetic Markers
keywords: Mitochondrial encephalomyopathy; Molecular genetics; Muscle biopsy; mtDNA