Precision medicine in early-onset epilepsy: The KCNQ2 paradigm

Abstract

The identification of the genetic causes and the underlying pathogenic mechanisms in early-onset epilepsies has proved to be essential in improving the efficacy of therapeutic decisions and the overall patient management, especially in the era of precision medicine. We report an infant presenting with a cluster of focal motor seizures with autonomic manifestations at day 3 of life. Electroencephalograms showed multifocal epileptic abnormalities and a burst-suppression pattern. Neurological examination showed poor visual fixation and hypotonia. Neuroimaging was normal. Seizures remitted with phenytoin and were well-controlled after the switch to oral carbamazepine. In the hypothesis of a genetic etiology, next-generation sequencing panel for epileptic encephalopathies was performed and identified a de novo missense mutation in KCNQ2 : c.1742G>A; p.(Arg581Gln) (NM_172107.2). This case report highlights the importance of the early recognition of the electroclinical phenotype and the detection of the underlying genetic cause in the implementation of “tailored” therapies in early-onset genetic epilepsies.