Preliminary Study About A Significant and Treatable Cause of Epileptic Encephalopathy: GRIN2D Mutation

Year 2021, Volume: 5 Issue: 2, 109 - 117, 30.08.2021

Gültekin Kutluk Nadide Cemre Randa

https://doi.org/10.30565/medalanya.891938

Abstract

Aim: The GRIN2D gene mutation causes severe forms of epileptic encephalopathy. NMDAR antagonists and magnesium sulfate could be useful as adjunctive therapy to control seizures in individuals with GRIN2D encephalopathy. The aim of this study was to describe the clinical features and treatment options of GRIN2D encephalopathy.

Methods: Patients followed up with epileptic encephalopathy in our pediatric neurology clinic were investigated for genetic etiology using next-generation sequencing (NGS)-based tests. Patients with the GRIN2D mutation were overviewed for clinical and genetic characteristics.

Results: A total of 53 patients were screened and GRIN2D mutations (c.3684_3685insGA, c.3248_3254del, c.1579G>T, c.47_49del) were detected in four patients. Occipital epileptic activity was frequently detected among our patients. Three patients received memantine treatment for intractable epilepsy and remained seizure-free.

Conclusion: GRIN2D encephalopathy is a treatable epileptic encephalopathy, and its recognition is important in terms of outcomes. Occipital epilepsy is generally benign, but developmental and epileptic encephalopathies such as GRIN2D encephalopathy should be considered in the presence of concomitant developmental delay.

Keywords

developmental delay, epileptic encephalopathy, GRIN2D, memantine, NMDA

Epileptik Ensefalopatinin Önemli ve Tedavi Edilebilir Bir Nedeni Hakkında Ön Çalışma: GRIN2D Mutasyonu

Abstract

Amaç: GRIN2D gen mutasyonu, ağır epileptik ensefalopatiye neden olur. NMDAR antagonistleri ve magnezyum, GRIN2D ensefalopatili bireylerde nöbetleri kontrol etmek için faydalı bir tedavi seçeneği olabilir. Bu çalışmanın amacı GRIN2D ensefalopatisinin klinik özellikleri ile tedavi seçeneklerini tanımlamaktır.

Yöntemler: Çocuk nöroloji kliniğimizde epileptik ensefalopati ile izlenen hastalar genetik etiyoloji açısından yeni nesil dizileme yöntemi tabanlı testler ile incelendi. GRIN2D mutasyonu olan hastalar klinik ve genetik özellikler açısından değerlendirildi.

Bulgular: Toplam 53 hasta tarandı. 4 hastada GRIN2D mutasyonları (c.3684_3685insGA, c.3248_3254del, c.1579G>T, c.47_49del) tespit edildi. Hastalarımızda oksipital epileptik aktivite sıklıkla tespit edildi. 3 hastaya inatçı epilepsi için memantin tedavisi başlandı ve bu hastalar nöbetsiz olarak takip edilmekteler.

Sonuç: GRIN2D ensefalopati, tedavi edilebilir bir epileptik ensefalopatidir ve hastanın sağkalımı açısından tanınması önemlidir. Oksipital epilepsi genellikle iyi huyludur, ancak eşlik eden gelişimsel gecikme varlığında GRIN2D ensefalopatisi gibi gelişimsel ve epileptik ensefalopatiler akla gelmelidir.

Keywords

gelişme geriliği, GRIN2D, NMDA, epileptik ensefalopati, memantin

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