Migrating partial seizures of infancy is an early onset epileptic encephalopathy syndrome that is typically resistant to treatment. The most common cause is a gain of function mutation in the potassium channel KCNT1. The antiarrhythmic drug quinidine is a partial antagonist of KCNT1 and hence may be a candidate drug for treatment of this condition. We report the case of a child with migrating partial seizures of infancy secondary to an activating mutation in KCNT1 treated with quinidine. Treatment with quinidine was correlated with a marked reduction in seizure frequency and improved psychomotor development.

BackgroundThe homeobox transcription factor Engrailed2 (En2) has been studied extensively in neurodevelopment, particularly in the midbrain/hindbrain region and cerebellum, where it exhibits dynamic patterns of expression and regulates cell patterning and morphogenesis. Because of its roles in regulating cerebellar development and evidence of cerebellar pathology in autism spectrum disorder (ASD), we previously examined an ENGRAILED2 association and found evidence to support EN2 as a susceptibility gene, a finding replicated by several other investigators. However, its functions at the cell biological level remain undefined. In the mouse, En2 gene is expressed in granule neuron precursors (GNPs) just as they exit the cell cycle and begin to differentiate, raising the possibility that En2 may modulate these developmental processes.MethodsTo define En2 functions, we examined proliferation, differentiation and signaling pathway activation in En2 knockout (KO) and wild-type (WT) GNPs in response to a variety of extracellular growth factors and following En2 cDNA overexpression in cell culture. In vivo analyses of cerebellar GNP proliferation as well as responses to insulin-like growth factor-1 (IGF1) treatment were also conducted.ResultsProliferation markers were increased in KO GNPs in vivo and in 24-h cultures, suggesting En2 normally serves to promote cell cycle exit. Significantly, IGF1 stimulated greater DNA synthesis in KO than WT cells in culture, a finding associated with markedly increased phospho-S6 kinase activation. Similarly, there was three-fold greater DNA synthesis in the KO cerebellum in response to IGF1 in vivo. On the other hand, KO GNPs exhibited reduced neurite outgrowth and differentiation. Conversely, En2 overexpression increased cell cycle exit and promoted neuronal differentiation.ConclusionsIn aggregate, our observations suggest that the ASD-associated gene En2 promotes GNP cell cycle exit and differentiation, and modulates IGF1 activity during postnatal cerebellar development. Thus, genetic/epigenetic alterations of EN2 expression may impact proliferation, differentiation and IGF1 signaling as possible mechanisms that may contribute to ASD pathogenesis.

Objective: Improvement in epilepsy care requires standardized methods to assess disease severity. We report the results of implementing common data elements (CDEs) to document epilepsy history data in the electronic medical record (EMR) after 12 months of clinical use in outpatient encounters. Methods: Data regarding seizure frequency were collected during routine clinical encounters using a CDE-based form within our EMR. We extracted CDE data from the EMR and developed measurements for seizure severity and seizure improvement scores. Seizure burden and improvement was evaluated by patient demographic and encounter variables for in-person and telemedicine encounters. Results: We assessed a total of 1696 encounters in 1038 individuals with childhood epilepsies between September 6, 2019 and September 11, 2020 contributed by 32 distinct providers. Childhood absence epilepsy (n = 121), Lennox-Gastaut syndrome (n = 86), and Dravet syndrome (n = 42) were the most common epilepsy syndromes.Overall, 43% (737/1696) of individuals had at least monthly seizures, 17% (296/1696) had a least daily seizures, and 18% (311/1696) were seizure-free for >12 months.Quantification of absolute seizure burden and changes in seizure burden over time differed between epilepsy syndromes, including high and persistent seizure burden in patients with Lennox-Gastaut syndrome. Individuals seen via telemedicine or in-person encounters had comparable seizure frequencies. Individuals identifying as Hispanic/Latino, particularly from postal codes with lower median household incomes, were more likely to have ongoing seizures that worsened over time.