Acetazolamide-Responsive Episodic Ataxia Linked to Novel Splice Site Variant in FGF14 Gene

  • M. Schesny
  • F. Joncourt
  • Alexander A. TarnutzerEmail author
Short Report


Here we describe the case of a patient with episodic dizziness and gait imbalance for 7 years and a negative family history. On clinical examination, interictally, the patient presented with gaze-evoked nystagmus and rebound nystagmus and slight dysarthria. MRI of the brain was normal and peripheral-vestibular function was bilaterally intact. Based on genetic testing (episodic ataxia panel), a heterozygote splice site variant in intron 1 of the FGF14 gene was identified. This report adds important new evidence to previous observations that pathogenic variants in the FGF14 gene may result in variable phenotypes, either in progressive spinocerebellar ataxia (type 27) or in episodic ataxia as in our case. Our patient responded well to acetazolamide (reduction in the frequency of attacks by about two thirds), supporting the hypothesis of a sodium channelopathy.


Hereditary ataxia Channelopathy Cerebellum Drug treatment Haploinsufficiency 


Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Informed Consent

The final version of this manuscript has been seen by the patient and written informed consent for publication has been retrieved from the patient.


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of NeurologyUniversity Hospital ZurichZurichSwitzerland
  2. 2.Division of Human Genetics, Department of PediatricsUniversity Hospital BerneBerneSwitzerland
  3. 3.University of ZurichZurichSwitzerland

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