title: Myelin protein zero Arg36Gly mutation with very late onset and rapidly progressive painful neuropathy.
abstract: Mutations in myelin protein zero (MPZ) protein result in a wide spectrum of peripheral neuropathies, from congenital hypomyelinating to late onset sensory and motor axonal forms. In some patients, neuropathic pain can be a prominent symptom, making the diagnosis challenging mainly in those with other risk factors for neuropathy. We describe a 77-year-old woman with impaired glucose tolerance presenting with rapidly progressive axonal neuropathy leading to excruciating pain and severe weakness of lower limbs within 2 years from the onset. Her son abruptly complained of similar painful symptoms at the age of 47 years. Molecular analysis revealed a novel heterozygous missense mutation (c.106A>G) in MPZ exon 2, causing the substitution of arginine-36 with glycine in the extracellular domain. Our observation suggests that MPZ-related neuropathy should be considered in the diagnostic work up of patients with painful axonal neuropathy even presenting with rapid progression and at a very late age of onset.
authors.affiliation: Neuromuscular Diseases Unit, IRCCS Foundation, ‘‘Carlo Besta’’ Neurological Institute, Via Celoria, 11, 20133 Milan, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Dacci
authors.forename: Franco
authors.initials: F
authors.lastname: Taroni
authors.forename: Eleonora Dalla
authors.initials: ED
authors.lastname: Bella
authors.forename: Micaela
authors.initials: M
authors.lastname: Milani
authors.forename: Davide
authors.initials: D
authors.lastname: Pareyson
authors.forename: Michela
authors.initials: M
authors.lastname: Morbin
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Lauria
mesh_terms: D000368:Aged; D019943:Amino Acid Substitution; D004247:DNA / Q000235:genetics; D005260:Female; D020233:Gait Disorders, Neurologic / Q000209:etiology; D018149:Glucose Intolerance / Q000209:etiology; D006801:Humans; D018763:Muscle Fatigue / Q000502:physiology; D018908:Muscle Weakness / Q000191:economics / Q000209:etiology; D009154:Mutation / Q000235:genetics* / Q000502:physiology*; D018993:Myelin P0 Protein / Q000235:genetics*; D009431:Neural Conduction; D009460:Neurologic Examination; D010146:Pain / Q000209:etiology; D010523:Peripheral Nervous System Diseases / Q000150:complications / Q000235:genetics* / Q000473:pathology; D011129:Polyradiculoneuropathy / Q000209:etiology / Q000235:genetics / Q000473:pathology
chemical_list: D018993:Myelin P0 Protein; D004247:DNA