Search Results (18)

Background/Objectives: Infantile epileptic spasms syndrome (IESS) is a severe epilepsy of infancy. Corticotropin (ACTH) and vigabatrin are the only FDA-approved therapies. The efficacy of ACTH together with the strong convulsant effects of corticotropin-releasing hormone (CRH) suggests that excess CRH, secondary to impaired ACTH feedback, may contribute to spasms. We therefore hypothesized that CRH receptor 1 (CRHR1) antagonists would suppress spasms in a route- and drug-dependent manner. Methods: Using our validated rat model of IESS, in which prenatal priming with betamethasone was followed by postnatal triggering of spasms with N-methyl-D-aspartic acid (NMDA), we tested two CRHR1 antagonists, CP376395 and SN003, delivered intracranially (via intracerebroventricular or intraparenchymal infusion) or systemically. Results: Intracerebroventricular infusion of both antagonists suppressed spasms, with CP376395 providing more consistent effects. Intraparenchymal administration into the hypothalamic arcuate nucleus also reduced spasms, whereas misses into the mammillary bodies were ineffective, highlighting site specificity. Systemic administration yielded divergent results: SN003 robustly suppressed spasms, whereas CP376395 unexpectedly exacerbated them. No sex differences were observed. Conclusions: These findings demonstrate that CRHR1 blockade modifies experimental spasms in a route- and drug-specific manner and implicates discrete hypothalamic circuits, particularly those including the arcuate nucleus, in spasm generation. The divergent systemic responses between CP376395 and SN003 likely reflect differences in CRHR1 engagement (competitive and non-competitive antagonism, respectively) as well as differences in binding properties that may include differential network interactions beyond local CRH signaling or duration of receptor occupancy. In conclusion, SN003 may be a better option than CP376395 for further development as a CRHR1-targeted therapy pending additional pharmacokinetic/pharmacodynamic studies. Further work should explore dosing paradigms of CP376395 to determine if a therapeutic range for CP376395 exists. Full article

Infantile Epileptic Spasms Syndrome (IESS) is a devastating epileptic encephalopathy of infancy that carries a high risk of lifelong neurodevelopmental disability. Timely diagnosis is critical, as every week of delay in effective treatment is associated with worse cognitive outcomes. Although synchronized electroencephalogram (EEG) and surface electromyography (EMG) recordings capture both the electrophysiological and motor signatures of spasms, accurate automated detection remains challenging due to the non-stationary nature of the signals and the absence of physiologically plausible inter-modal fusion in current deep learning approaches. We introduce IESS-FusionNet, an end-to-end dual-stream framework specifically designed for accurate, real-time IESS detection from simultaneous EEG and EMG. Each modality is processed by a dedicated Unimodal Encoder that hierarchically integrates Continuous Wavelet Transform, Spatio-Temporal Convolution, and Bidirectional Mamba to efficiently extract frequency-specific, spatially structured, local and long-range temporal features within a compact module. A novel Cross Time-Mixing module, built upon the linear recurrent attention of the Receptance Weighted Key Value (RWKV) architecture, subsequently performs efficient, time-decaying, bidirectional cross-modal integration that explicitly respects the causal and physiological properties of cortico-muscular coupling during spasms. Evaluated on an in-house clinical dataset of synchronized EEG-EMG recordings from infants with confirmed IESS, IESS-FusionNet achieves 89.5% accuracy, 90.7% specificity, and 88.3% sensitivity, significantly outperforming recent unimodal and multimodal baselines. Comprehensive ablation studies validate the contribution of each component, while the proposed cross-modal fusion requires approximately 60% fewer parameters than equivalent quadratic cross-attention mechanisms, making it suitable for real-time clinical deployment. IESS-FusionNet delivers an accurate, computationally efficient solution with physiologically inspired cross-modal fusion for the automated detection of infantile epileptic spasms, offering promise for future clinical applications in reducing diagnostic delay. Full article

Background and Objectives: Infantile spasms (ISs), or West syndrome (WS), represent an early-onset epileptic encephalopathy in which diverse structural, genetic, metabolic, infectious, and neurocutaneous conditions converge on a shared pattern of hypsarrhythmia, clustered spasms, and later developmental impairment. Growing use of genomic diagnostics has revealed that variants in STXBP1, KCNQ2, GRIN2A, GRIN2B, and TSC-related genes are more common than previously recognized and can be linked to partially actionable pathways. This review aimed to synthesize current evidence on the multifactorial etiology, network-based pathogenesis, and evolving targeted therapies for ISs, with particular attention to TSC-related forms. Materials and Methods: A structured narrative review was undertaken of publications from 1990 to 2025 in PubMed, Scopus, Web of Science, and Embase using terms related to ISs, WS, genetics, mTOR, ACTH, vigabatrin, ketogenic diet, and precision therapies. Authoritative guidance from ILAE and AAN was incorporated. Clinical, molecular, and therapeutic data were grouped under etiological, pathogenetic, and management domains. Results: Structural causes remained the largest group, but combined genetic, genetic–structural, and metabolic etiologies accounted for about one third of contemporary cohorts. Early network disruption involving cortex, thalamus, basal ganglia, and brainstem, together with imbalances in NGF, BDNF, and IGF-1, explained why distinct primary insults produce a uniform electroclinical phenotype. Early treatment with ACTH or high dose prednisolone, with or without vigabatrin, was consistently associated with higher electroclinical remission and better developmental outcome. Everolimus and related mTOR inhibitors showed benefit in TSC-associated ISs, while agents directed at NMDA receptors or KCNQ channels are emerging for genotype defined subgroups. Conclusions: ISs should be approached as a heterogeneous but mechanistically convergent disorder in which rapid diagnosis, parallel genetic testing, and early disease modifying therapy improve prognosis. Integration of molecular profiling with standardized outcome monitoring is likely to move management from symptomatic seizure control to pathway-specific intervention. Full article

Epilepsy affects approximately 50 million people worldwide, with nearly one-third of patients experiencing inadequate seizure control with conventional anti-epileptic drugs. The GABAergic system, responsible for inhibitory neurotransmission in the central nervous system, represents a critical target for seizure management. GABA aminotransferase (GABA-T), the enzyme responsible for GABA catabolism, has emerged as a particularly attractive therapeutic target. Inhibition of GABA-T increases synaptic GABA availability, enhancing inhibitory neurotransmission and raising the seizure threshold. Vigabatrin, an irreversible GABA-T inhibitor, has demonstrated remarkable efficacy in specific epilepsy syndromes, particularly infantile spasms and refractory partial seizures. However, its clinical utility is tempered by the risk of irreversible visual field defects, necessitating careful patient selection and monitoring. This review examines the molecular biology of GABA-T, the mechanisms of action of its inhibitors, clinical applications, safety considerations, and emerging developments in this therapeutic area. We discuss the structure–function relationships of GABA-T, the pharmacology of vigabatrin and experimental inhibitors, clinical efficacy across various epilepsy syndromes, adverse effect profiles, and future directions including novel inhibitors with improved safety profiles. Understanding the role of GABA-T in epilepsy pathophysiology and the therapeutic potential of its inhibitors provides insights into rational drug design and personalized treatment strategies for epilepsy management. Full article

Background: Spectrin proteins are critical cytoskeleton components that maintain cellular structure and mediate intracellular transport. Pathogenic variants in SPTBN1, encoding βII-spectrin, have been associated with various neurodevelopmental disorders, including developmental delay, intellectual disability, autism spectrum disorder, and epilepsy. Here we report a Korean infant with infantile epileptic spasms syndrome (IESS) and an SPTBN1 mutation and provide a review of this mutation. Methods: The genomic data of the patient were analyzed by whole exome sequencing. A comprehensive literature review was conducted to identify and analyze all reported SPTBN1 variants, resulting in a dataset of 60 unique mutations associated with neurodevelopmental phenotypes. Case Presentation: A 10-month-old Korean female presented with IESS associated with a de novo heterozygous SPTBN1 mutation (c.785A>T; p.Asp262Val). The patient exhibited global developmental delay, microcephaly, hypotonia, spasticity, and MRI findings of diffuse cerebral atrophy and corpus callosum hypoplasia. Electroencephalography revealed hypsarrhythmia, confirming the diagnosis of IESS. Seizures persisted despite initial treatment with vigabatrin and steroids. Genetic analysis identified a likely pathogenic variant within the calponin homology 2 (CH2) domain of SPTBN1. Conclusions: This is the first report of an association between IESS and an SPTBN1 CH2 domain mutation in a Korean infant. This finding expands the clinical spectrum of SPTBN1-related disorders and suggests domain-specific effects may critically influence phenotypic severity. Further functional studies are warranted to elucidate the pathogenic mechanisms of domain-specific variants. Full article

Objectives: The aim of this study was to evaluate the effectiveness of sequential treatments with adrenocorticotropic hormone (ACTH) or ketogenic diet therapy (KDT) in infants with infantile epileptic spasms syndrome (IESS) who did not achieve seizure freedom after initial treatment with either KDT or ACTH. Methods: We conducted a cohort study following a parallel-cohort randomized controlled trial comparing KDT with ACTH as first-line treatment for IESS. Infants who failed to respond were switched per protocol to the alternative treatment (ACTH or KDT) or, if this was not feasible or unsuccessful, to anti-seizure medications (ASMs). The primary outcome was the frequency of sustained seizure freedom at last follow-up. Results: Of 101 infants allocated to the initial treatment phase, N = 67 required further treatment. Of these, 31% (21/67) achieved sustained seizure freedom after the second treatment phase, and 15% (7/46) after rescue treatment with ASMs. KDT as the second treatment achieved sustained seizure freedom in 50% (12/24), compared to 19% (3/16) with ACTH and 9% (2/22) with ASMs. The cumulative response rate after the first and second treatments was 64% for the KDT-ACTH sequence and 68% for the ACTH-KDT sequence. The cumulative response after all three treatment phases was 78% (KDT-ACTH-ASM) and 72% (ACTH-KDT-ASM), respectively. Conclusions: KDT is at least as effective as ACTH as a second treatment and significantly more effective than ASMs in achieving sustained seizure freedom in infants with IESS. Full article

Tools for measuring the likelihood of relapse in infantile epileptic spasms syndrome (IESS) treatment could aid clinicians in making critical management decisions. High-frequency oscillations (HFOs), transient bursts of electroencephalography (EEG) activity with frequencies beyond 80 Hz, are a new and promising noninvasive biomarker. The present study aimed to investigate the association between the Burden of Amplitudes and Epileptiform Discharges (BASED) scores, an interictal EEG grading scale for IESS, and scalp HFOs in patients with IESS. The study enrolled 50 patients, 25 with a clinical diagnosis of IESS and 25 without epilepsy. The percentage of patients with at least one scalp HFO detected, stratified by BASED scores, differed significantly: for BASED scores ≤ 2, 7.7%; for 3, 16.7%; for 4, 87.5%; and for 5, 100% (p < 0.001). Compared with BASED scores ≤ 2, the median scalp HFO detection rate was significantly highest for BASED scores of 5 (median [IQR]: 6.24 [2.25–8.32], p < 0.001), followed by BASED scores of 4. The scalp HFO detection rates showed a better performance in estimating patients with BASED scores of 4 and 5. It is hoped that scalp HFOs can be used as an objective indicator to validate the results of BASED scores. Full article

Infantile spasms are common in Down Syndrome (DS), but the mechanisms by which DS predisposes to this devastating epilepsy syndrome are unclear. In general, neuronal excitability and therefore seizure predisposition results from an imbalance of excitation over inhibition in neurons and neural networks of the brain. Animal models provide clues to mechanisms and thereby provide potential therapeutic approaches. Ts65Dn mice have been the most widely used animal model of DS. In this model, there is evidence for both abnormal cerebral excitation and inhibition: infantile spasms-like clinical and electrographic activity can be elicited by the administration of gamma-aminobutyric acid (GABA)-B receptor agonist, gamma-butyrolactone (GBL), and depolarizing GABA-A responses persist beyond the age of their usual switch to hyperpolarized responses. But despite its widespread use, the Ts65Dn model may be suboptimal because of the absence of numerous genes that are triplicated in human DS and the presence of numerous genes that are not triplicated in human DS. Recently, a transchromosomic mouse artificial chromosome 21 (TcMAC21) mouse model has been developed, which carries a copy of human chromosome 21 and therefore has a genetic composition more similar to human DS. As in Ts65Dn mice, exposure of TcMAC21 mice to GBL results in epileptic spasms, and aberrant excitation has also been demonstrated. This review summarizes excitatory and inhibitory dysfunction in models of DS that may play a role in the generation of seizures and infantile spasms, providing a perspective on past studies and a prelude for future ones. Further elucidation will hopefully lead to rational therapeutic options for DS children with infantile spasms. Full article

The ARX mutations encompass a nearly continuous spectrum of neurodevelopmental disorders (NDDs), ranging from lissencephaly to Proud syndrome, as well as infantile spasms without brain malformations, and including both syndromic and non-syndromic intellectual disabilities (IDs). We describe worsening neuropsychiatric symptoms in the offspring of a Korean family with ID/developmental delay (DD) caused by a novel ARX p.Lys385Ter variant. Sequential genetic testing was performed to investigate the ID, DD, agenesis of the corpus callosum (ACC), and developmental epileptic encephalopathy (DEE) observed in the proband. A comprehensive trio clinical exome sequencing approach using a Celemics G-Mendeliome Clinical Exome Sequencing Panel was employed. Given the clinical manifestations observed in the proband, gene panel sequencing identified a heterozygous ARX variant, c.1153A>T/p.Lys385Ter (Reference transcript ID: NM_139058.3), as the most likely cause of ID, DD, ACC, and DEE in the proband. Sanger sequencing confirmed the segregation of the ARX variant, c.1153A>T/p.Lys385Ter, with the phenotype and established the maternally inherited dominant status of the heterozygous variant in the patient, as well as in her grandmother, mother, and aunt. Our case report adds to the understanding of the female phenotype in ARX-related disorders caused by loss-of-function variants in the ARX gene. Genetic counseling for ARX families should proceed with caution, as female carriers can exhibit a wide range of phenotypes, from normal cognitive development to ID/DD, ACC, and DEE. Full article

The NR4A2 gene encodes an orphan transcription factor of the steroid–thyroid hormone–retinoid receptor superfamily. This review focuses on the clinical findings associated with the pathogenic variants so far reported, including three unreported cases. Also, its role in neurodegenerative diseases, such as Parkinson’s or Alzheimer’s disease, is examined, as well as a brief exploration on recent proposals to develop novel therapies for these neurological diseases based on small molecules that could modulate NR4A2 transcriptional activity. The main characteristic shared by all patients is mild to severe developmental delay/intellectual disability. Moderate to severe disorder of the expressive and receptive language is present in at least 42%, while neuro-psychiatric issues were reported in 53% of patients. Movement disorders, including dystonia, chorea or ataxia, are described in 37% patients, although probably underestimated because of its frequent onset in late adolescence–young adulthood. Finally, epilepsy was surprisingly present in 42% of patients, being drug-resistant in three of them. The age at onset varied widely, from five months to twenty-six years, as did the classification of epilepsy, which ranged from focal epilepsy to infantile spasms or Lennox–Gastaut syndrome. Accordingly, we propose that NR4A2 should be considered as a first-tier target gene for the genetic diagnosis of developmental and epileptic encephalopathy. Full article

Infantile epileptic spasms syndrome (IESS) is a devastating developmental epileptic encephalopathy (DEE) consisting of epileptic spasms, as well as one or both of developmental regression or stagnation and hypsarrhythmia on EEG. A myriad of aetiologies are associated with the development of IESS; broadly, 60% of cases are thought to be structural, metabolic or infectious in nature, with the remainder genetic or of unknown cause. Epilepsy genetics is a growing field, and over 28 copy number variants and 70 single gene pathogenic variants related to IESS have been discovered to date. While not exhaustive, some of the most commonly reported genetic aetiologies include trisomy 21 and pathogenic variants in genes such as TSC1, TSC2, CDKL5, ARX, KCNQ2, STXBP1 and SCN2A. Understanding the genetic mechanisms of IESS may provide the opportunity to better discern IESS pathophysiology and improve treatments for this condition. This narrative review presents an overview of our current understanding of IESS genetics, with an emphasis on animal models of IESS pathogenesis, the spectrum of genetic aetiologies of IESS (i.e., chromosomal disorders, single-gene disorders, trinucleotide repeat disorders and mitochondrial disorders), as well as available genetic testing methods and their respective diagnostic yields. Future opportunities as they relate to precision medicine and epilepsy genetics in the treatment of IESS are also explored. Full article

Aicardi Syndrome (AIC) is a rare neurodevelopmental disorder recognized by the classical triad of agenesis of the corpus callosum, chorioretinal lacunae and infantile epileptic spasms syndrome. The diagnostic criteria of AIC were revised in 2005 to include additional phenotypes that are frequently observed in this patient group. AIC has been traditionally considered as X-linked and male lethal because it almost exclusively affects females. Despite numerous genetic and genomic investigations on AIC, a unifying X-linked cause has not been identified. Here, we performed exome and genome sequencing of 10 females with AIC or suspected AIC based on current criteria. We identified a unique de novo variant, each in different genes: KMT2B, SLF1, SMARCB1, SZT2 and WNT8B, in five of these females. Notably, genomic analyses of coding and non-coding single nucleotide variants, short tandem repeats and structural variation highlighted a distinct lack of X-linked candidate genes. We assessed the likely pathogenicity of our candidate autosomal variants using the TOPflash assay for WNT8B and morpholino knockdown in zebrafish (Danio rerio) embryos for other candidates. We show expression of Wnt8b and Slf1 are restricted to clinically relevant cortical tissues during mouse development. Our findings suggest that AIC is genetically heterogeneous with implicated genes converging on molecular pathways central to cortical development. Full article

The CYFIP2 protein (cytoplasmic FMR1-interacting protein 2) is part of the WAVE regulatory complex (WRC). CYFIP2 was recently correlated to neurological disorders by the association of the R87C variant with early infantile epileptic encephalopathy (EIEE) patients. In this set of syndromes, the epileptic spasms and seizures since early childhood lead to impaired neurological development in children. Inside the WRC, the variant residue is at the CYFIP2 and WAVE1 protein interface. Thus, the hypothesis is that the R87C modification weakens this interaction, allowing the WRC complex’s constant activation. This work aimed to investigate the impacts of the mutation on the structure of the WRC complex through molecular dynamics simulation. For that, we constructed WRC models containing WAVE1-NCKAP1 proteins complexed with WT or R87C CYFIP2. Our simulations showed a flexibilization of the loop comprising residues 80–110 due to the loss of contacts between internal residues in the R87C CYFIP2 as well as the key role of residues R/C87, E624, and E689 in structural modification. These data could explain the mechanism by which the mutation impairs the stability and proper regulation of the WRC. Full article

(1) Background: West syndrome is a severe, refractory, epileptic syndrome that usually appears in infancy or early childhood. ACTH is one of the more effective drugs for treating this condition. (2) Aim of the study and methods: The objective of our study was to examine short-term efficacy (during treatment schedule) and long-term outcome of intramuscular 0.02 mg/kg/day ACTH (tetracosactide) depot, used concomitantly with other antiepileptic drugs (AEDs) in patients with infantile spasms who did not achieve seizure cessation or relapse when taking only the AEDs. The drug efficacy was evaluated in retrospective and prospective analyses of 50 patients diagnosed with infantile spasms. (3) Results: Complete cessation of spasms was achieved in 42 cases (84%). EEG improvement was seen in 41 (82%) patients who responded to ACTH therapy. Information on the clinical course of 28 patients was obtained duringlong-term follow-up. In 17 (60.7%) cases, seizures were still present. Normal or near-normal development was observed in 11 out of 28 children (39%). ACTH used concomitantly with other AEDis a highly effective treatment with acceptable side effects. (4) Conclusion: Randomized controlled clinical trialswith long-term follow-up are needed to compare the effectiveness of ACTH in polytherapy and monotherapy. Dyskinesias as a potential side effect observed in our study group should be investigated in the following studies. Full article

Neuroinflammation has been implicated in the pathogenesis of West syndrome (WS). Inflammatory cytokines, including interleukin-1β(IL-1β), have been reported to be associated with epilepsy. However, the assessment of cytokine changes in humans is not always simple or deterministic. This study aimed to elucidate the immunological mechanism of WS. We examined the intracellular cytokine profiles of peripheral blood cells collected from 13 patients with WS, using flow cytometry, and measured their serum cytokine levels. These were compared with those of 10 age-matched controls. We found that the WS group had significantly higher percentages of inter IL-1β, interleukin-1 receptor antagonist (IL-1RA)-positive monocytes, and interferon gamma (IFN-γ) in their CD8+ T cells than the control group. Interestingly, the group with sequelae revealed significantly lower levels of intracellular IFN-γ and IL-6 in their CD8+ T and CD4+ T cells, respectively, than the group without sequelae. There was no correlation between the ratios of positive cells and the serum levels of a particular cytokine in the WS patients. These cytokines in the peripheral immune cells might be involved in the neuroinflammation of WS, even in the absence of infectious or immune disease. Overall, an immunological approach using flow cytometry analysis might be useful for immunological studies of epilepsy. Full article