Christina BENETOU, Stavroula PAPAİLİOU, Despoina MARİTSİ, Katherine ANAGNOSTOPOULOU, Harry KONTOS, Georgios VARTZELİS

A novel de novo KCNQ2 mutation in a child with treatmentresistant early-onset epileptic encephalopathy

Mutations in KCNQ2 gene, encoding for voltage-gated K+ channel subunit,may result in a wide spectrum of early-onset epileptic disorders. Thephenotype of the disease varies from “benign familial neonatal seizures”to “severe epileptic encephalopathies”. In this report, we present a novelmutation [namely: c.683A>G (p.His228Arg)], as a presumable cause of severeinfantile-onset neonatal seizures, in a 3-month old boy. The seizures havebeen poorly responsive to various pharmacological treatments, with phenytoinand carbamazepine presenting with the most favourable results so far. Thestudy of our patient could help to further clarify the clinical manifestationsof KCNQ2 mutations, revealing a previously unreported mutation.

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