伊藤 進
   Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine
   Position   Assistant Professor
Article types Case report
Language English
Peer review Peer reviewed
Title A de novo GABRB2 variant associated with myoclonic status epilepticus and rhythmic high-amplitude delta with superimposed (poly) spikes (RHADS)
Journal Formal name:Epileptic Disorders:
Abbreviation:Epileptic Disord
ISSN code:12949361/19506945
Domestic / ForeginForegin
Publisher JOHN LIBBEY EUROTEXT
Volume, Issue, Page 22(4),476-481頁
Author and coauthor NISHIKAWA Aiko†, OTNI Yui, ITO Susumu, NAGATA Satoru, SHIOTA Mutsuki, TAKANASHI Jun-ichi, NAKASHIMA Mitsuko, SAITSU Hirotomo, MATSUMOTO Naomichi, OGUNI Hirokazu*
Publication date 2020/08/01
Summary We report a child who developed myoclonic status epilepticus
(MSE) at four months of age, associated with rhythmic high-amplitude
delta and superimposed (poly) spikes (RHADS), harbouring a GABRB2 (2
subunit of the GABA A receptor) variant. The patient was treated under a
presumptive diagnosis of neonatal-onset Alpers syndrome (AS) and underwent
targeted sequence analysis for POLG1 (polymerase gamma 1) and
subsequent whole-exome sequence analysis (WES). The patient is currently
a 10-year, eight-month-old boy, suffering from daily MSE associated with
RHADSand severe global developmental delay from early infancy. Although
POLG1 mutation was negative, WES revealed a de novo missense variant
of GABRB2 (NM_021911.2: c.784G>T, p.[Val262Phe]). Based on a review of
case series with GABRB2 variants, we found that five of the 18 cases shared
the clinical and EEG characteristics associated with our patient. In summary,
this de novo GABRB2 variant was associated with an AS phenotype,
characterized by treatment-resistant MSE and RHADS, and may represent
an alternative aetiology for neonatal-onset AS without POLG1 mutation
[Published with video sequence].
DOI 10.1684/epd.2020.1183