EPILEPSY CAUSED BY PCDH19 GENE MUTATION: A REVIEW OF LITERATURE AND THE AUTHORS’ OBSERVATIONS

Mutation in the PCDH19 gene was first described by L.M. Dibbens et al. in 2008. Mutations in this gene are associated with epilepsy and mental retardation limited to females. The clinical manifestations that are observed in some patients with PCDH19 mutation and Dravet syndrome that is caused by mutation in the SCN1A gene include the onset of febrile and afebrile seizures in infancy, serial seizures during fever, and regression in development after the onset of seizures. Due to the fact that the two diseases have common clinical signs, it is best to test for PCDH19 mutation in patients with the clinical picture of Dravet syndrome and a negative test for SCN1A. In general, the number of scientific papers devoted to analysis and recommendations for the choice of therapy in patients with rare genetic pathology is small now. We analyzed the specific features of clinical signs and therapy in our two observed female patients aged 4 and 11 years with verified PCDH19 mutation. Both patients were noted to have severe epilepsy with febrile convulsions with the development of status epilepticus and to be unresponsive to antiepileptic therapy. The use of different antiepileptic drugs (valproate, oxcarbazepine, phenobarbital, topiramate, levetiracetam) at different combinations failed to control the course of epilepsy in the 4-year-old patient whereas the 11-year-old patient who took a combination of valproic acid and benzodiazepines achieved a positive effect.

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