Myotonia congenita--a cause of muscle weakness and stiffness.
BACKGROUND
A 56-year-old woman was referred to a neurogenetic clinic with a history of stiffness and transient weakness. A previous needle electromyogram had confirmed the presence of myotonia, but a muscle biopsy had revealed no evidence of dystrophy.


METHODS
Neurological examination, electrophysiological studies and genetic testing.


METHODS
Recessive myotonia congenita (Becker's disease).


RESULTS
Explanation of the nature of the disease and treatment with mexiletine 200 mg twice daily.
Chrestian
Nicolas
N
University of Laval, QC, Canada.
Puymirat
Jack
J
Bouchard
Jean-Pierre
JP
Dupré
Nicolas
N
D003937:Diagnosis, Differential; D004576:Electromyography; D005260:Female; D005808:Genes, Recessive; D006801:Humans; D008801:Mexiletine / Q000627:therapeutic use; D008875:Middle Aged; D018908:Muscle Weakness / Q000209:etiology* / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology*; D009224:Myotonia Congenita / Q000150:complications* / Q000235:genetics / Q000503:physiopathology*; D009460:Neurologic Examination
D008801:Mexiletine