Perampanel treatment in IQSEC2-associated epileptic encephalopathy

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Mutations in the IQSEC2 gene cause developmental disorders (OMIM#309530) accompanied by epileptic encephalopathy, movement disorders, dysmorphic facial features, autism spectrum disorders and intellectual disability. The IQSEC2 protein controls excitatory synaptic transmission, regulating responses mediated by glutamate receptors at excitatory synapses, and it is also involved in transmembrane transport, lipid transformation and actin cytoskeleton reorganization, playing an important role in learning processes and memory mechanisms. Polymorphic epileptic seizures that occur at an early age contribute to developmental regression; they are pharma-resistant. The authors describe a clinical case of a patient with drug-resistant epileptic encephalopathy, dysmorphic facial features, autism spectrum disorders, intellectual disability, and absence of speech associated with a hemizygous X-linked de novo mutation in IQSEC2 (chrX:53241815C>T; c.2984G>A; p.Arg995Gln) identified using next-generation sequencing. The use of perampanel as an additional therapy to topiramate made it possible to achieve remission in a patient with focal seizures and bilateral tonic-clonic seizures in combination with other types of seizures (epileptic spasms and tonic seizures).

Keywords:

X-linked intellectual disability

mutations of IQSEC2

epileptic encephalopathy

autism

treatment of epilepsy

perampanel

Authors:

Gamirova R.G.

Kazan (Volga region) Federal University

ORCID: 0000-0002-8582-592X

Gamirova R.R.

Kanazawa University

ORCID: 0000-0003-0441-9418

Gorobets E.A.

Kazan (Volga region) Federal University

ORCID: 0000-0002-3859-5543

Received:

23.01.2025

Accepted:

28.01.2025

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