Vitamin B6–Responsive Epilepsy due to a Novel KCNQ2 Mutation

Kerstin Alexandra Klotz; Johannes R. Lemke; Rudolf Korinthenberg; Julia Jacobs

doi:10.1055/s-0037-1601857

Neuropediatrics, Table of Contents

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

¹Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany

,

Johannes R. Lemke

²Institute of Human Genetics, University Hospitals, University of Leipzig, Leipzig, Germany

,

Rudolf Korinthenberg

¹Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany

,

Julia Jacobs

¹Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany

› Author Affiliations

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

Full Text

References

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