Febrile seizures are the most common neurologic disorder in childhood. Physicians should be familiar with the proper evaluation and management of this common condition.

To identify novel pathogenic gene of febrile seizures (FS)/epilepsy with antecedent FS (EFS+).

Febrile seizures (FS) are the most common form of epilepsy in children between six months and five years of age. FS is a self-limited type of fever-related seizure. However, complicated prolonged FS can lead to complex partial epilepsy. We found that among the GABAA receptor subunit (GABR) genes, most variants associated with FS are harbored in the γ2 subunit (GABRG2). Here, we characterized the effects of eight variants in the GABAA receptor γ2 subunit on receptor biogenesis and channel function. Two-thirds of the GABRG2 variants followed the expected autosomal dominant inheritance in FS and occurred as missense and nonsense variants. The remaining one-third appeared as de novo in the affected probands and occurred only as missense variants. The loss of GABAA receptor function and dominant negative effect on GABAA receptor biogenesis likely caused the FS phenotype. In general, variants in the GABRG2 result in a broad spectrum of phenotypic severity, ranging from asymptomatic, FS, genetic epilepsy with febrile seizures plus (GEFS+), and Dravet syndrome individuals. The data presented here support the link between FS, epilepsy, and GABRG2 variants, shedding light on the relationship between the variant topological occurrence and disease severity.

Febrile seizures (FS) is the most common convulsive disorder in children, but there have been no clinical and experimental studies of the possible treatment of FS with herbal medicines, which are widely used in Asian countries. Paeoniflorin (PF) is a major bioactive component of Radix Paeoniae alba, and PF-containing herbal medicines have been used for neuromuscular, neuropsychiatric, and neurodegenerative disorders. In this study, we analyzed the anticonvulsive effect of PF and Keishikashakuyaku-to (KS; a PF-containing herbal medicine) for hyperthermia-induced seizures in immature rats as a model of human FS. When immature (P5) male rats were administered PF or KS for 10 days, hyperthermia-induced seizures were significantly suppressed compared to control rats. In cultured hippocampal neurons, PF suppressed glutamate-induced elevation of intracellular Ca(2+) ([Ca(2+)](i)), glutamate receptor-mediated membrane depolarization, and glutamate-induced neuronal death. In addition, PF partially suppressed the elevation in [Ca(2+)](i) induced by activation of the metabotropic glutamate receptor 5 (mGluR5), but not that mediated by α-amino-3-hydroxy-5-methyl-4-isoxazolpropionic acid (AMPA) or N-methyl-D-aspartate (NMDA) receptors. However, PF did not affect production or release of γ-aminobutyric acid (GABA) in hippocampal neurons. These results suggest that PF or PF-containing herbal medicines exert anticonvulsive effects at least in part by preventing mGluR5-dependent [Ca(2+)](i) elevations. Thus, it could be a possible candidate for the treatment of FS in children.

The current study was conducted to describe the findings of brain perfusion, hippocampal volumetric, and diffusion-weighted imaging (DWI) in children aged six months to seven years with febrile status epilepticus (FSE) and focal febrile seizures (FFS) when compared with age and gender-matched controls.

To identify the genetic cause in a large family with febrile seizures (FS) and temporal lobe epilepsy (TLE) and subsequently search for additional mutations in a cohort of 107 families with FS, with or without epilepsy.

Accurate diagnosis of febrile seizures in children presenting after paroxysmal episodes associated with fever, is hampered by the lack of objective postictal biomarkers. The aim of our study was to investigate whether FS are associated with increased levels of serum copeptin, a robust marker of arginine vasopressin secretion.

Environmental exposure early in development plays a role in susceptibility to disease in later life. Here, we demonstrate that prolonged febrile seizures induced by exposure of rat pups to a hyperthermic environment enhance seizure susceptibility not only in these hyperthermia-treated rats but also in their future offspring, even if the offspring never experience febrile seizures. This transgenerational transmission was intensity-dependent and was mainly from mothers to their offspring. The transmission was associated with DNA methylation. Thus, our study supports a "Lamarckian"-like mechanism of pathogenesis and the crucial role of epigenetic factors in neurological conditions.

The purpose of this study was to investigate knowledge, principles, and practices concerning the management of children with febrile seizures among pediatricians in Greece. A cross-sectional study was performed across Greece. Pediatricians completed an anonymous and voluntary 11-item questionnaire about their knowledge, attitudes, and practices with respect to the management of febrile seizures; the survey also collected demographic data. It was first administered in paper form in October 2017. This was followed by an online survey performed between June and August of 2018 and publicized by medical boards across Greece. Descriptive statistics and comparisons between groups were conducted with the significance level set at p ≤ 0.05. We recorded 457 responses. Pediatricians admitted to modifying their advice to the parents of children with febrile seizures by suggesting more "aggressive" fever management at low temperatures or systematically (63%), referral to a specialist after any episode of febrile seizures (63%), or hospitalization in a subsequent episode (67%), even though 72% admitted these practices were of no efficacy. Almost one in three pediatricians (28%) believed aggressive management of fever could delay the onset of febrile seizures; increasing age was associated with this perception. A minority (28%) would make parents aware of febrile seizures before a first episode regardless of family history; 38% would do so in the event of family history.

Primary blood coagulation and wound sealing are orchestrated by von Willebrand factor (VWF), a large multimeric glycoprotein. Upon release of arginine vasopressin (AVP), VWF containing high molecular weight multimers is secreted. By measuring copeptin, the C-terminal part of the AVP prohormone, we recently found strongly increased AVP levels in children with febrile seizures (FS) as compared to children with fever but without seizures. It is unknown if increased AVP levels in FS are of any biological function. Therefore, our a priori hypothesis was that children with FS have increased VWF parameters in parallel with higher AVP levels.

Mutations in the voltage-gated sodium channel (VGSC) gene SCN1A, encoding the Nav1.1 channel, are responsible for a number of epilepsy disorders including genetic epilepsy with febrile seizures plus (GEFS+) and Dravet syndrome (DS). Patients with SCN1A mutations often experience prolonged early-life febrile seizures (FSs), raising the possibility that these events may influence epileptogenesis and lead to more severe adult phenotypes. To test this hypothesis, we subjected 21-23-day-old mice expressing the human SCN1A GEFS+ mutation R1648H to prolonged hyperthermia, and then examined seizure and behavioral phenotypes during adulthood. We found that early-life FSs resulted in lower latencies to induced seizures, increased severity of spontaneous seizures, hyperactivity, and impairments in social behavior and recognition memory during adulthood. Biophysical analysis of brain slice preparations revealed an increase in epileptiform activity in CA3 pyramidal neurons along with increased action potential firing, providing a mechanistic basis for the observed worsening of adult phenotypes. These findings demonstrate the long-term negative impact of early-life FSs on disease outcomes. This has important implications for the clinical management of this patient population and highlights the need for therapeutic interventions that could ameliorate disease progression.

Diffusion magnetic resonance imaging (MRI) studies have demonstrated acute white matter changes following prolonged febrile seizures (PFS), but their longer-term evolution is unknown. We investigated a population-based cohort to determine white matter diffusion properties 8 years after PFS.

Somatic recordings from CA1 pyramidal cells indicated a persistent upregulation of the h-current (I(h)) after experimental febrile seizures. Here, we examined febrile seizure-induced long-term changes in I(h) and neuronal excitability in CA1 dendrites. Cell-attached recordings showed that dendritic I(h) was significantly upregulated, with a depolarized half-activation potential and increased maximal current. Although enhanced I(h) is typically thought to be associated with decreased dendritic excitability, whole-cell dendritic recordings revealed a robust increase in action potential firing after febrile seizures. We turned to computational simulations to understand how the experimentally observed changes in I(h) influence dendritic excitability. Unexpectedly, the simulations, performed in three previously published CA1 pyramidal cell models, showed that the experimentally observed increases in I(h) resulted in a general enhancement of dendritic excitability, primarily due to the increased I(h)-induced depolarization of the resting membrane potential overcoming the excitability-depressing effects of decreased dendritic input resistance. Taken together, these experimental and modeling results reveal that, contrary to the exclusively anti-convulsive role often attributed to increased I(h) in epilepsy, the enhanced I(h) can co-exist with, and possibly even contribute to, persistent dendritic hyperexcitability following febrile seizures in the developing hippocampus.

Prolonged febrile seizures (PFS) are the commonest cause of childhood status epilepticus and are believed to carry a risk of neuronal damage, in particular to the mesial temporal lobe. This study was designed to determine: i) the effect of prolonged febrile seizures on white matter and ii) the temporal evolution of any changes seen. 33 children were recruited 1 month following PFS and underwent diffusion tensor imaging (DTI) with repeat imaging at 6 and 12 months after the original episode of PFS. 18 age-matched healthy control subjects underwent similar investigations at a single time point. Tract-based spatial statistics (TBSS) was used to compare fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) between patients and controls on a voxel-wise basis within the white matter skeleton. Widespread reductions in FA along multiple white matter tracts were found at 1 and 6 months post-PFS, but these had resolved at 12 months. At one month post-PFS the main changes seen were reductions in AD but at 6 months these had predominantly changed to increases in RD. These widespread white matter changes have not previously been noted following PFS. There are many possible explanations, but one plausible hypothesis is that this represents a temporary halting of normal white matter development caused by the seizure, that then resumes and normalises in the majority of children.

Febrile seizures (FS) are the most prevalent type of seizures in children. Existing predictive models for FS exhibit limited predictive ability. To build a better-performing predictive model, a retrospective analysis study was conducted on febrile children who visited the Children's Hospital of Shanghai from July 2020 to March 2021. These children were divided into training set (n = 1453), internal validation set (n = 623) and external validation set (n = 778). The variables included demographic data and complete blood counts (CBCs). The least absolute shrinkage and selection operator (LASSO) method was used to select the predictors of FS. Multivariate logistic regression analysis was used to develop a predictive model. The coefficients derived from the multivariate logistic regression were used to construct a nomogram that predicts the probability of FS. The calibration plot, area under the receiver operating characteristic curve (AUC), and decision curve analysis (DCA) were used to evaluate model performance. Results showed that the AUC of the predictive model in the training set was 0.884 (95% CI 0.861 to 0.908, p < 0.001) and C-statistic of the nomogram was 0.884. The AUC of internal validation set was 0.883 (95% CI 0.844 to 0.922, p < 0.001), and the AUC of external validation set was 0.858 (95% CI 0.820 to 0.896, p < 0.001). In conclusion, the FS predictive model constructed based on CBCs in this study exhibits good predictive ability and has clinical application value.

Febrile seizures represent a serious adverse event following measles, mumps and rubella (MMR) vaccination. We conducted a series of genome-wide association scans comparing children with MMR-related febrile seizures, children with febrile seizures unrelated to vaccination and controls with no history of febrile seizures. Two loci were distinctly associated with MMR-related febrile seizures, harboring the interferon-stimulated gene IFI44L (rs273259: P = 5.9 × 10(-12) versus controls, P = 1.2 × 10(-9) versus MMR-unrelated febrile seizures) and the measles virus receptor CD46 (rs1318653: P = 9.6 × 10(-11) versus controls, P = 1.6 × 10(-9) versus MMR-unrelated febrile seizures). Furthermore, four loci were associated with febrile seizures in general, implicating the sodium channel genes SCN1A (rs6432860: P = 2.2 × 10(-16)) and SCN2A (rs3769955: P = 3.1 × 10(-10)), a TMEM16 family gene (ANO3; rs114444506: P = 3.7 × 10(-20)) and a region associated with magnesium levels (12q21.33; rs11105468: P = 3.4 × 10(-11)). Finally, we show the functional relevance of ANO3 (TMEM16C) with electrophysiological experiments in wild-type and knockout rats.

Neuroaxonal damage is reflected by serum neurofilament light chain (sNfL) values in a variety of acute and degenerative diseases of the brain. The aim of this study was to investigate the impact of febrile and epileptic seizures on sNfL, serum copeptin, and prolactin levels in children compared with children with febrile infections without convulsions.

Prolonged and focal febrile seizures (FSs) have been associated with the development of temporal lobe epilepsy (TLE), although the underlying mechanism and the contribution of predisposing risk factors are still poorly understood. Using a kainate model of TLE, we previously provided strong evidence that interruption of astrocyte gap junction-mediated intercellular communication represents a crucial event in epileptogenesis. To elucidate this aspect further, we induced seizures in immature mice by hyperthermia (HT) to study the consequences of FSs on the hippocampal astrocytic network. Changes in interastrocytic coupling were assessed by tracer diffusion studies in acute slices from mice 5 days after experimental FS induction. The results reveal that HT-induced FSs cause a pronounced reduction of astrocyte gap junctional coupling in the hippocampus by more than 50%. Western blot analysis indicated that reduced connexin43 protein expression and/or changes in the phosphorylation status account for this astrocyte dysfunction. Remarkably, uncoupling occurred in the absence of neuronal death and reactive gliosis. These data provide a mechanistic link between FSs and the subsequent development of TLE and further strengthen the emerging view that astrocytes have a central role in the pathogenesis of this disorder. © 2016 Wiley Periodicals, Inc.

We report a family with complex febrile seizures (FS). The proband is a 15-year-old boy with seizures that persisted beyond 6 years of age. His father, aunt, and cousin also have the histories of FS until 8, 9, and 8 years old, respectively. A base substitution 5569G-->T of voltage-gated sodium channel alpha-1 subunit gene was found in DNA derived from the affected members of this family.

Febrile seizures (FS) are the most common seizure syndrome and are potentially a prelude to more severe epilepsy. Although zinc (Zn(2+)) metabolism has previously been implicated in FS, whether or not variation in proteins essential for Zn(2+) homeostasis contributes to susceptibility is unknown. Synaptic Zn(2+) is co-released with glutamate and modulates neuronal excitability. SLC30A3 encodes the zinc transporter 3 (ZNT3), which is primarily responsible for moving Zn(2+) into synaptic vesicles. Here we sequenced SLC30A3 and discovered a rare variant (c.892C > T; p.R298C) enriched in FS populations but absent in population-matched controls. Functional analysis revealed a significant loss-of-function of the mutated protein resulting from a trafficking deficit. Furthermore, mice null for ZnT3 were more sensitive than wild-type to hyperthermia-induced seizures that model FS. Together our data suggest that reduced synaptic Zn(2+) increases the risk of FS and more broadly support the idea that impaired synaptic Zn(2+) homeostasis can contribute to neuronal hyperexcitability.