Limbic encephalitis with anti-GAD antibodies and Thomsen myotonia: a casual or causal association?

Abstract

The association between hereditary myotonic disorders and epilepsy is seldom described in the literature. To date, few reports have dealt with dystrophic myotonias, whereas a single case demonstrating an association between sporadic congenital myotonia and epilepsy was recently reported in a patient carrying a de novo mutation of the CLCN1 gene. Additional evidence for a role of CLCN1 in the pathogenesis of epilepsy is derived from large-scale exome analysis of ion channel variants and expression studies. Here, we describe the first case of association between familial Thomsen myotonia and epilepsy. All the affected members of a two-generation family presented myotonia and disclosed a pathogenic mutation in CLCN1. In addition, one individual experienced epileptic seizures due to limbic encephalitis (LE) with anti-GAD antibodies. The occurrence of the two diseases in this patient could be a chance association, however, CLCN1 mutation, as a susceptibility factor for epilepsy through dysfunction of GABAA inhibitory signalling, cannot be ruled out as a possible influence.

• Authors: Laura Licchetta, Francesca Bisulli, Ilaria Naldi, Greta Mainieri, Paolo Tinuper
• Journal: Epileptic disorders : international epilepsy journal with videotape (Epileptic Disord) Vol. 16 Issue 3 Pg. 362-5 (Sep 2014) ISSN: 1294-9361 [Print] France
• PMID: 25036107 (Publication Type: Case Reports, Journal Article)

Chemical References

• CLC-1 channel
• Chloride Channels
• Glutamate Decarboxylase

Topics

• Adolescent
• Chloride Channels (genetics)
• Glutamate Decarboxylase (genetics, immunology)
• Humans
• Limbic Encephalitis (complications, genetics, immunology)
• Male
• Mutation
• Myotonia Congenita (complications, genetics, immunology)
• Pedigree