title: Myotonic dystrophy type 2 with focal asymmetric muscle weakness and no electrical myotonia.
abstract: Genetically proven myotonic dystrophy type 2 (DM2) was found in a 61-year-old woman with creatine kinase (CK) elevation and only isolated weakness of one triceps. There was no clinical or electrical myotonia. Electromyography (EMG) showed only scattered fibrillation potentials and short duration motor unit potentials. Muscle biopsy showed nonspecific myopathic features and highly atrophic fibers with nuclear clumps. DM2 should be considered in patients with focal proximal weakness and abnormal EMG without myotonic discharges.
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota, 55905, USA. Milone.Margherita@mayo.edu
authors.forename: Margherita
authors.initials: M
authors.lastname: Milone
authors.forename: Sat D
authors.initials: SD
authors.lastname: Batish
authors.forename: Jasper R
authors.initials: JR
authors.lastname: Daube
mesh_terms: D003402:Creatine Kinase / Q000378:metabolism; D004576:Electromyography / Q000379:methods; D005260:Female; D006801:Humans; D008875:Middle Aged; D018908:Muscle Weakness / Q000209:etiology* / Q000473:pathology; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology*; D009223:Myotonic Dystrophy / Q000150:complications* / Q000235:genetics / Q000473:pathology*; D016601:RNA-Binding Proteins / Q000235:genetics
chemical_list: C433227:CNBP protein, human; D016601:RNA-Binding Proteins; D003402:Creatine Kinase