Electroencephalographic Features in KCNT1-related Epilepsy
Abstract number :
1.205
Submission category :
4. Clinical Epilepsy / 4B. Clinical Diagnosis
Year :
2023
Submission ID :
263
Source :
www.aesnet.org
Presentation date :
12/2/2023 12:00:00 AM
Published date :
Authors :
Presenting Author: Pei-Yu Wu, MD – Taichung Veterans General Hospital
Ching-Shiang Chi, M.D. Prof. – Division of Pediatric Neurology, Children’s Medical Center – Taichung Veterans General Hospital; Hsiu-Fen Lee, M.D. Ph.D – Division of Pediatric Neurology, Children’s Medical Center – Taichung Veterans General Hospital; Chi-Ren Tsai, Ph.D – Division of Pediatric Neurology, Children’s Medical Center – Taichung Veterans General Hospital; Yao-Lun Yang, M.D. – Division of Pediatric Neurology, Children’s Medical Center – Taichung Veterans General Hospital
Rationale: Mutations in KCNT1 gene have been associated with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), epilepsy of infancy with migrating focal seizures (EIMFS), and developmental and epileptic encephalopathy (DEE). The aim of this study was to describe KCNT1-related EEG features to refine its phenotype spectrum and outcomes.
Methods: Five individuals, four males and one female, who were diagnosed with KCNT1-related epilepsy, were recruited. Clinical manifestations, EEG features, brain MRI findings, gene variants, and clinical outcomes were analyzed.
Results: The age at seizure onset of individuals one, two, three, four, and five was three weeks, two months, two months, eight months, and one year and two months of age, respectively. The clinical seizure semiology was focal tonic or clonic seizures with or without evolving to bilateral tonic-clonic seizures and focal nonmotor seizures in individual 1; focal tonic or clonic seizures with or without evolving to bilateral tonic-clonic seizures and focal or generalized myoclonic seizures in individuals two, four, and five; alternating focal tonic spasms in individual three. The serial EEG features were as follows: focal spikes with or without burst suppression in individuals one, two, four, and five; focal spikes over the posterior hemisphere and ictal shifting from one hemisphere to the other in individual three, which was compatible with the features of EIMFS. The brain MRI findings of five individuals were unremarkable. The results of genetic testing revealed KCNT1 c.1283G >A gene variant in individual one, KCNT1 c.1294G >A gene variant in individual two, KCNT1 c.1013C >G gene variant in individual three, and KCNT1 c.862G >A gene variant individuals four and five. The five individuals had psychomotor regression after the stormy phase of clinical seizures, mimicking neurodegeneration. The clinical outcomes are devastating during the period of follow-up, (i.e., individual 1, 2 and 3) were in bedridden status and individuals four and five could move with assistance.
Conclusions: With the advances of molecular biological techniques, we could detect KCNT1-related epilepsy earlier. However, clinical manifestations and EEG features are fundamental to distinguish EIMFS, non-EIMFS DEE and other phenotypes.
Funding: This research received no external funding.
Clinical Epilepsy