Focal seizures in a patient with myotonic disorder type 2 co-segregating with a chloride voltage-gated channel 1 gene mutation: a case report

J Med Case Rep. 2016 Jun 7;10:167. doi: 10.1186/s13256-016-0958-8.


Background: Myotonic dystrophy type 2 is a multisystem disorder with both neurological and non-neurological signs and symptoms. Seizures are not a commonly associated neurological feature of this disorder.

Case presentation: A 57-year-old white American man presented with a long history of clinical and electrophysiological features of a myotonic disorder. He also developed multiple episodes of focal seizures and underwent a series of investigations which showed no structural or metabolic etiology. Genetic testing revealed that he had an expansion mutation in CCHC-type zinc finger, nucleic acid binding protein gene confirming the diagnosis of myotonic disorder type 2 and carried a mutation in the chloride voltage-gated channel 1 gene.

Conclusions: We report a rare association between myotonic dystrophy type 2 and a seizure disorder. The pathophysiology of a possible relationship between these two neurological conditions is discussed.

Keywords: CNBP and CLCN1 gene mutations; Case report; Myotonia; Myotonic dystrophy type 2; Seizures.

Publication types

  • Case Reports

MeSH terms

  • Chloride Channels / genetics*
  • Humans
  • Male
  • Middle Aged
  • Mutation / genetics*
  • Myotonic Dystrophy / complications*
  • Myotonic Dystrophy / genetics
  • Seizures / complications*
  • Seizures / genetics


  • CLC-1 channel
  • Chloride Channels