Fluctuating neuromuscular transmission defects and inverse acetazolamide response in episodic ataxia type 2 associated with the novel CaV2.1 single amino acid substitution R2090Q.
We report on a 51-year-old woman with episodic ataxia type 2 (EA2) and a novel CaV2.1 C-terminal single amino acid substitution (R2090Q). She had a 4-year history of acute episodes with ataxia, hemihypesthesia and hemicrania. Furthermore, fluctuating neuromuscular transmission abnormalities rarely described in patients with EA2 were clinically and electrophysiologically documented in this patient. Upon initiation of acetazolamide treatment she experienced a dose-dependent severe increase of attack frequency and severity along with a shorter attack duration, while she responded well to subsequent therapy with 4-aminopyridine.
Melzer
Nico
N
Department of Neurology, Julius Maximilian University, Würzburg, Germany.
Classen
Joseph
J
Reiners
Karlheinz
K
Buttmann
Mathias
M
D000086:Acetazolamide / Q000627:therapeutic use*; D019943:Amino Acid Substitution; D001763:Blepharoptosis / Q000209:etiology; D020864:Calcium Channels, N-Type / Q000235:genetics*; D002257:Carbonic Anhydrase Inhibitors / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000187:drug effects / Q000294:innervation* / Q000502:physiology; D017354:Point Mutation / Q000235:genetics / Q000502:physiology; D020754:Spinocerebellar Ataxias / Q000188:drug therapy* / Q000503:physiopathology*; D009435:Synaptic Transmission / Q000502:physiology*
D000086:Acetazolamide; D020864:Calcium Channels, N-Type; D002257:Carbonic Anhydrase Inhibitors