Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Oct 28;8(6):a006236.
doi: 10.1101/mcs.a006236. Print 2022 Oct.

Episodic ataxia type 2 (EA2) with interictal myokymia and focal dystonia

Emilie Neerup Nielsen  1 , Birna Ásbjörnsdóttir  2 , Lisbeth Birk Møller  1 , Jørgen Erik Nielsen  2   3 , Suzanne Granhøj Lindquist  1   2   3
Affiliations

Episodic ataxia type 2 (EA2) with interictal myokymia and focal dystonia

Emilie Neerup Nielsen et al. Cold Spring Harb Mol Case Stud. .

Abstract

Episodic ataxia type 1 and 2 (EA1 and EA2) are the most well-described of the episodic ataxias. They are autosomal dominantly inherited early-onset diseases characterized by attacks of cerebellar dysfunction. EA1 is clinically characterized by short episodes of ataxia with interictal myokymia, whereas EA2 is characterized by longer-lasting recurrent ataxia, slurred speech, and interictal nystagmus. We report on a patient with EA2 with interictal focal dystonia and also interictal myokymia, which is hitherto not reported as an interictal feature associated to EA2. The patient carries a previously described heterozygous pathogenic de novo frameshift variant in the CACNA1A gene, establishing the diagnosis of EA2. She had symptom onset at age 13 and from age 48 she developed interictal myokymia and focal dystonia as illustrated in Supplemental Movie S1. We conclude that interictal myokymia and focal dystonia may be interictal features associated to EA2 caused by the cerebellar pathophysiology of EA2. Episodes of ataxia were successfully treated with acetazolamide in low dose, whereas the interictal features were unresponsive to acetazolamide.

Keywords: episodic ataxia.

PubMed Disclaimer

Similar articles

  • Episodic ataxias 1 and 2.
    Baloh RW. Baloh RW. Handb Clin Neurol. 2012;103:595-602. doi: 10.1016/B978-0-444-51892-7.00042-5. Handb Clin Neurol. 2012. PMID: 21827920 Review.
  • Therapy of episodic ataxias: case report and review of the literature.
    Orsucci D, Raglione LM, Mazzoni M, Vista M. Orsucci D, et al. Drugs Context. 2019 Mar 11;8:212576. doi: 10.7573/dic.212576. eCollection 2019. Drugs Context. 2019. PMID: 30891074 Free PMC article. Review.
  • Familial Episodic Ataxias and Related Ion Channel Disorders.
    Jen J. Jen J. Curr Treat Options Neurol. 2000 Sep;2(5):429-431. doi: 10.1007/s11940-000-0041-y. Curr Treat Options Neurol. 2000. PMID: 11096768
  • [Hereditary episodic ataxia].
    Riant F, Vahedi K, Tournier-Lasserve E. Riant F, et al. Rev Neurol (Paris). 2011 May;167(5):401-7. doi: 10.1016/j.neurol.2010.10.016. Epub 2011 Apr 13. Rev Neurol (Paris). 2011. PMID: 21492892 Review. French.
  • Episodic Ataxia Type 2 – RETIRED CHAPTER, FOR HISTORICAL REFERENCE ONLY.
    Spacey S. Spacey S. 2003 Feb 24 [updated 2015 Oct 15]. In: Adam MP, Feldman J, Mirzaa GM, Pagon RA, Wallace SE, Amemiya A, editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993–2025. 2003 Feb 24 [updated 2015 Oct 15]. In: Adam MP, Feldman J, Mirzaa GM, Pagon RA, Wallace SE, Amemiya A, editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993–2025. PMID: 20301674 Free Books & Documents. Review.
See all similar articles

Cited by

References

    1. Giunti P, Mantuano E, Frontali M. 2020. Episodic ataxias: faux or real? Int J Mol Sci 21: 6472. 10.3390/ijms21186472 - DOI - PMC - PubMed
    1. Hu Y, Jiang H, Wang Q, Xie Z, Pan S. 2013. Identification of a novel nonsense mutation p.Tyr1957Ter of CACNA1A in a Chinese family with episodic ataxia 2. PLoS ONE 8: e56362. 10.1371/journal.pone.0056362 - DOI - PMC - PubMed
    1. Indelicato E, Boesch S. 2021. From genotype to phenotype: expanding the clinical spectrum of CACNA1A variants in the era of next generation sequencing. Front Neurol 12: 639994. 10.3389/fneur.2021.639994 - DOI - PMC - PubMed
    1. Jen JC, Graves TD, Hess EJ, Hanna MG, Griggs RC, Baloh RW; CINCH investigators. 2007. Primary episodic ataxias: diagnosis, pathogenesis and treatment. Brain 130: 2484–2493. 10.1093/brain/awm126 - DOI - PubMed
    1. Mantuano E, Romano S, Veneziano L, Gellera C, Castellotti B, Caimi S, Testa D, Estienne M, Zorzi G, Bugiani M, et al. 2010. Identification of novel and recurrent CACNA1A gene mutations in fifteen patients with episodic ataxia type 2. J Neurol Sci 291: 30–36. 10.1016/j.jns.2010.01.010 - DOI - PubMed

Supplementary concepts

LinkOut - more resources