A Rare Cause of Drug-Resistant Epilepsy and Nonconvulsive Status Epilepticus: Ring Chromosome 20

Abstract

Introduction: Ring chromosome 20 presents as a drug-resistant epilepsy syndrome with complex partial seizures and nonconvulsive status epilepticus. Other characteristics are mild to moderate learning disability, and various dysmorphic features. Its diagnosis necessitates a high index of suspicion since the incidence is rare and there is no a specific phenotypic expression.

Case: Here we present a child admitted to our pediatric neurology clinic with complex partial seizures and nonconvulsive status epilepticus. Cytogenic studies revealed ring chromosome 20.

Conclusion: Cytogenic studies should be part of the evaluation in epilepsy patients who presented with drug resistant epilepsy of unknown etiology.

Keywords

• Ring chromosome 20
• drug-resistant epilepsy
• Nonconvulsive

Dirençli epilepsi ve nonkonvülsif status epileptikusun nadir bir nedeni: Ring 20 kromozomu

Öz

Giriş: Ring kromozom 20 antiepileptik ilaçlara dirençli nöbetler ve nonkonvülzif status epileptikus ile prezante olur. Hafif–orta öğrenme güçlüğü ve çeşitli dismorfik özellikler eşlik eden diğer bulgulardır. Nadir görülmesi ve spesifik fenotipik özelliğinin olmaması nedeniyle tanısı yüksek şüphe gerektirmektedir.

Olgu: Bu yazıda çocuk nöroloji kliniğimize kompleks parsiyel nöbet ve nonkonvülzif status epileptikus ile başvuran, sitogenetik incelemede ring kromozom 20 tespit edilen bir çocuk hasta sunuldu.

Sonuç: Etiyolojisi belli olmayan antiepileptik ilaçlara dirençli epilepsi ile izlenen hastalarda sitogenetik incelemeler değerlendirmenin bir parçası olmalıdır.

Anahtar Kelimeler

• ring kromozom 20
• antiepileptik ilaçlara
• dirençli epilepsi

Kaynakça

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