Erken Başlangıçlı Tekrarlayan Ateşli Nöbetlerde Pre-Prognostik Bir Gösterge Olarak SCN1A Genetik Testinin Uygulanması

Abstract

Amaç: 1 yaş ve altı tekrarlayan ateşli nöbeti olan çocukların epileptik yatkınlıklarının SCN1A gen dizi analizi kullanılarak daha erken tahmin edilip edilemeyeceğini belirlemek.

Gereç ve Yöntemler: Çalışmaya çocuk acil servisine ateşli nöbet ile başvuran 0-18 yaş arası 55 hasta dahil edildi. Hastalar, bir yaş ve altında tekrarlayan (iki veya daha fazla) ateşli nöbetleri olma, normal kraniyal görüntülemeye sahip olma ve merkezi sinir sistemi enfeksiyonları ekarte edilme kriterlerine göre seçildi. SCN1A gen dizi analizi, yeni nesil dizileme yöntemi kullanılarak gerçekleştirildi.

Bulgular: c.1738C> T ve c.4181C> T daha önce bildirilmişken, c.2914-1G> A ve c.473A>G, yeni heterozigot hastalığa neden olan SCN1A varyantlarıydı. 55 akraba olmayan aileden 5 çocuk için (% 9.09) c.1738C> T, c.2914-1G> A ve c.4181C> T varyanta sahip olan hastalar olası Dravet sendromu veya Dravet sendromu, ancak c.473A> G olan diğer ikisi ateşli nöbet artı genetik epilepsi fenotipi gösterdi.

Sonuç: Erken başlangıçlı ateşli nöbetlerde SCN1A genetik testinin önceden uygulanması, prognozu belirlemek ve uzun dönem takibi tasarlamak için klinik risk faktörlerinden daha önemli bir gösterge olabilir.

Keywords

• Ateşli nöbet
• SCN1A
• Dravet sendrom

Administration Of SCN1A Genetic Testing As A Pre-Prognostic Indicator in Early Onset Recurrent Febrile Seizures

Abstract

Objective: To determine whether the epileptic predispositions of recurrent febrile seizures (onset of age 1 and below) could be predicted earlier using analysis of SCN1A gene sequencing.

Material and Methods: The study included 55 patients aged between 0-18 who were admitted to pediatric emergency service with a febrile seizure. Patients were selected based on the criteria of presenting recurrent (two or more) febrile seizures with the onset of age one and below, having normal cranial imaging and central nervous system infections being ruled out. SCN1A gene sequence analysis was performed using the next-generation sequencing method.

Results: The c.1738C>T and c.4181C>T were the previously reported whereas the c.2914-1G>A and c.473A>G were novel SCN1A heterozygous disease-causing variants which were identified in five of 55 patients from 55 unrelated families (9.09%). The patients with c.1738C>T, c.2914-1G>A, and c.4181C>T variants presented probable Dravet syndrome or Dravet syndrome phenotype, but then the other two with c.473A> G demonstrated genetic epilepsy with febrile seizure plus.

Conclusion: Beforehand administration of SCN1A genetic testing in early-onset febrile seizures could be a more significant indicator rather than the clinical risk factors for determining the prognosis and designing the long-term follow-up. 

Keywords

• febrile seizures
• SCN1A
• Dravet sendrom

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