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Neuropediatrics 2017; 48(03): 199-204
DOI: 10.1055/s-0037-1601857
Short Communication
Georg Thieme Verlag KG Stuttgart, New York

Vitamin B6–Responsive Epilepsy due to a Novel KCNQ2 Mutation

Kerstin Alexandra Klotz
1   Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
,
Johannes R. Lemke
2   Institute of Human Genetics, University Hospitals, University of Leipzig, Leipzig, Germany
,
Rudolf Korinthenberg
1   Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
,
Julia Jacobs
1   Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
› Author Affiliations
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Publication History

20 February 2017

08 March 2017

Publication Date:
18 April 2017 (online)

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Abstract

Mutations in KCNQ2, encoding for subunits of potassium channels, are known to cause neonatal epileptic encephalopathy (NEE). Therapeutic options for these children are often limited. Recently, there are indications that some patients with KCNQ2 NEE show seizure response to vitamin B6 (VB6) therapy. We present a young infant with severe KCNQ2 encephalopathy resulting from a novel de novo mutation (c.1023G>C; p.(Gln341His)). In our patient, VB6 responsiveness could be demonstrated clearly by remarkable seizure-response to VB6 therapy and seizure exacerbation to discontinuation of VB6 therapy. The pathophysiology of VB6 response in potassium channel mutations is not understood. Some hypothetical mechanisms are currently in discussion. To identify the group of patients who benefits from VB6 therapy, further investigations are necessary.

Keywords

KCNQ2 - vitamin B6 - pyridoxine-responsive-epilepsy - neonatal epileptic encephalopathy
 

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