Ion channelopathies as a variant of etiopathogenetic substrate in convulsive syndrome: epilepsy caused by a mutation in the KCNB1 gene

Ion channelopathies (ICs) are the result of impaired or altered regulation of ion channel proteins because of hereditary or acquired alterations. In general clinical practice IСs have a multisystemic presentation; from the central nervous system the main clinical symptom complexes include epilepsy, ataxia of various genesis, impaired cognitive and behavioral functions, hyperkinetic disorder, cephalalgia, neuropathic pain, sensory disturbance, myokymia, myotonia, idiopathic muscle weakness, sleep disturbance, visual and hearing impairment. Nowadays ionic channelopathies are most commonly considered as a trigger of the development of epilepsy independently of the type of channels. Potassium channelopathies (PCs) are the most numerous and varied type of channelopathies in terms of structure, function, biophysical and pharmacological properties. The pathogenesis of PCs is based on the dysregulation of the transmembrane K + gradient, which in turn leads to a specific nosology depending on the potassium channel subtype.

Aim: to research the data of worldwide scientific publications with further structuring of information and to provide the main clinical and diagnostic characteristics of IC with optimal therapy of concomitant seizure conditions.

Material and methods. We have analyzed 25 scientific publications in MEDLINE, PubMed, Google Scholar, eLIBRARY database (using the keywords “ion channelopathies” and “KCNB1”): clinical trials, randomized controlled trials, systematic reviews, clinical cases from 2009 to 2024. Also, we presented a clinical case of a child with epilepsy caused by a mutation in the KCNB1 gene, showing a positive eff ect due to the targeted therapy.

Results. We considered the main epileptogenic PCs. ICs therapy represents symptomatic treatment. For a number of epileptogenic PCs, the therapeutic approach has a strictly specific and at once highly effective anticonvulsant therapy depending on the type of ion channel.

Conclusion. The treatment of epileptic manifestations of ion channelopathies should be determined not only by the generally accepted strategy based on the type and form of seizures but also in accordance to the identified genetic defect.

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