Myotonic dystrophy type 2 with focal asymmetric muscle weakness and no electrical myotonia.
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.
Milone
Margherita
M
Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota, 55905, USA. Milone.Margherita@mayo.edu
Batish
Sat D
SD
Daube
Jasper R
JR
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
C433227:CNBP protein, human; D016601:RNA-Binding Proteins; D003402:Creatine Kinase