title: "Mitochondrial neuropathies": A survey from the large cohort of the Italian Network.
abstract: Involvement of the peripheral nervous system in mitochondrial disorders has been previously reported. However, the prevalence of peripheral neuropathy in mitochondrial disorders is still unclear. Based on the large database of the "Nation-wide Italian Collaborative Network of Mitochondrial Diseases", we reviewed the clinical data of 1200 patients, with special regard to peripheral neuropathy (mean age at onset 24.3 ± 20.1 years; age at last evaluation 39.8 ± 22.3 years; females 52.7%; childhood onset [before age 16 years] 43.1%). Peripheral neuropathy was present in 143/1156 patients (12.4%), being one of the ten most common signs and symptoms. POLG mutations cause a potentially painful, axonal/mixed, mainly sensory polyneuropathy; TYMP mutations lead to a demyelinating sensory-motor polyneuropathy; SURF1 mutations are associated with a demyelinating/mixed sensory-motor polyneuropathy. The only mtDNA mutation consistently associated with peripheral neuropathy (although less severely than in the above-considered nuclear genes) was the m.8993T > G (or the rarer T > C) changes, which lead to an axonal, mainly sensory polyneuropathy. In conclusion, peripheral neuropathy is one of the most common features of a mitochondrial disorder, and may negatively impact on the quality of life of these patients. Furthermore, the presence or absence of peripheral neuropathy, as well as its specific forms and the association with neuropathic pain (indicative of a POLG-associated disease) can guide the molecular analysis.
authors.affiliation: Neurological Clinic, University of Pisa, Pisa, Italy. Electronic address: mancusomichelangelo@gmail.com.
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Mancuso
authors.affiliation: Neurological Clinic, University of Pisa, Pisa, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Orsucci
authors.affiliation: IRCCS S. Camillo, Venice, Italy.
authors.forename: Corrado
authors.initials: C
authors.lastname: Angelini
authors.affiliation: Unit of Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Hospital IRCCS, Rome, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Bertini
authors.affiliation: IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, and Neurology Unit, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy.
authors.forename: Valerio
authors.initials: V
authors.lastname: Carelli
authors.affiliation: Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy; Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
authors.forename: Giacomo Pietro
authors.initials: GP
authors.lastname: Comi
authors.affiliation: Department of Medicine, Surgery and Neurosciences, University Siena and Unit Clinical Neurology and Neurometabolic Diseases, AOUS, Siena, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Federico
authors.affiliation: Neuropediatric and Muscle Disorders Unit, University of Genoa and G. Gaslini Institute, Genoa, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Minetti
authors.affiliation: Neuromuscular Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy; Dino Ferrari Centre, University of Milan, Milan, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Moggio
authors.affiliation: Department of Neuroscience, University of Turin, Torino, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Mongini
authors.affiliation: Neurological Clinic, University of Verona, Verona, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Tonin
authors.affiliation: Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Toscano
authors.affiliation: Center of Myology and Neurodegenerative Diseases, G Gaslini Institute, Genova, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Bruno
authors.affiliation: Neurological Clinic, University of Pisa, Pisa, Italy.
authors.forename: Elena Caldarazzo
authors.initials: EC
authors.lastname: Ienco
authors.affiliation: Neurological Clinic, University Hospital Spedali Civili, Brescia, Italy.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Filosto
authors.affiliation: Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology-IRCCS, Milan, Italy.
authors.forename: Costanza
authors.initials: C
authors.lastname: Lamperti
authors.affiliation: Unit of Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Hospital IRCCS, Rome, Italy.
authors.forename: Daria
authors.initials: D
authors.lastname: Diodato
authors.affiliation: Child Neurology Unit, The Foundation "Carlo Besta" Institute of Neurology-IRCCS, Milan, Italy.
authors.forename: Isabella
authors.initials: I
authors.lastname: Moroni
authors.affiliation: Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy.
authors.forename: Olimpia
authors.initials: O
authors.lastname: Musumeci
authors.affiliation: Neurological Clinic, University of Padova, Padova, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Pegoraro
authors.affiliation: Neurological Clinic, University of Padova, Padova, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Spinazzi
authors.affiliation: Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Milan, Italy; Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
authors.forename: Naghia
authors.initials: N
authors.lastname: Ahmed
authors.affiliation: Neuromuscular Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy; Dino Ferrari Centre, University of Milan, Milan, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Sciacco
authors.affiliation: Department of Neuroscience, University of Turin, Torino, Italy.
authors.forename: Liliana
authors.initials: L
authors.lastname: Vercelli
authors.affiliation: Child Neurology Unit, The Foundation "Carlo Besta" Institute of Neurology-IRCCS, Milan, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Ardissone
authors.affiliation: Unit of Molecular Neurogenetics, The Foundation "Carlo Besta" Institute of Neurology-IRCCS, Milan, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Zeviani
authors.affiliation: Neurological Clinic, University of Pisa, Pisa, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Siciliano
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D028361:Mitochondrial Diseases / Q000453:epidemiology* / Q000235:genetics / Q000503:physiopathology; D010523:Peripheral Nervous System Diseases / Q000453:epidemiology* / Q000235:genetics / Q000503:physiopathology; D015995:Prevalence; D012189:Retrospective Studies; D055815:Young Adult
keywords: Disease registry; Mitochondrial myopathies; Neuropathy; Peripheral nerve; mtDNA