{"title":"Episodic ataxia type 2 (EA2) with interictal myokymia and focal dystonia.","authors":"Emilie Neerup Nielsen, Birna Ásbjörnsdóttir, Lisbeth Birk Møller, Jørgen Erik Nielsen, Suzanne Granhøj Lindquist","doi":"10.1101/mcs.a006236","DOIUrl":null,"url":null,"abstract":"<p><p>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 <i>CACNA1A</i> 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.</p>","PeriodicalId":10360,"journal":{"name":"Cold Spring Harbor Molecular Case Studies","volume":"8 6","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e2/ef/MCS006236Nie.PMC9632360.pdf","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cold Spring Harbor Molecular Case Studies","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1101/mcs.a006236","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MEDICINE, RESEARCH & EXPERIMENTAL","Score":null,"Total":0}
引用次数: 1
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.
期刊介绍:
Cold Spring Harbor Molecular Case Studies is an open-access, peer-reviewed, international journal in the field of precision medicine. Articles in the journal present genomic and molecular analyses of individuals or cohorts alongside their clinical presentations and phenotypic information. The journal''s purpose is to rapidly share insights into disease development and treatment gained by application of genomics, proteomics, metabolomics, biomarker analysis, and other approaches. The journal covers the fields of cancer, complex diseases, monogenic disorders, neurological conditions, orphan diseases, infectious disease, gene therapy, and pharmacogenomics. It has a rapid peer-review process that is based on technical evaluation of the analyses performed, not the novelty of findings, and offers a swift, clear path to publication. The journal publishes: Research Reports presenting detailed case studies of individuals and small cohorts, Research Articles describing more extensive work using larger cohorts and/or functional analyses, Rapid Communications presenting the discovery of a novel variant and/or novel phenotype associated with a known disease gene, Rapid Cancer Communications presenting the discovery of a novel variant or combination of variants in a cancer type, Variant Discrepancy Resolution describing efforts to resolve differences or update variant interpretations in ClinVar through case-level data sharing, Follow-up Reports linked to previous observations, Plus Review Articles, Editorials, and Position Statements on best practices for research in precision medicine.