Aug 2026· Brain & development (Tokyo. 1979)· Vol 48 5, pp.
104581
· 0 citations· 170 references
Medicine
TL;DR
Critical unmet needs include earlier molecular diagnosis, precision therapies targeting developmental outcomes beyond seizure control, and prospective international registries to characterize the long-term natural history of EIDEE.
Abstract
Early infantile developmental and epileptic encephalopathy (EIDEE) is among the most severe epilepsy syndromes, with onset before three months of age and an estimated incidence of approximately 10 per 100,000 live births. The 2022 International League Against Epilepsy classification unified the historically distinct Ohtahara syndrome and early myoclonic encephalopathy under a single diagnostic framework defined by frequent drug-resistant tonic and/or myoclonic seizures, an abnormal neurological examination, and an abnormal interictal electroencephalogram-most characteristically a burst-suppression pattern. This narrative review synthesizes the clinical, electrophysiological, neuroimaging, genetic, and therapeutic literature within the EIDEE framework. The clinical phenotype is characterized by central hypotonia, postnatal microcephaly, cortical visual impairment, and age-dependent syndromic evolution toward infantile epileptic spasms syndrome or Lennox-Gastaut syndrome in the majority of patients. Electroencephalography remains essential for syndromic classification, while systematic metabolic screening and early trio whole-exome or whole-genome sequencing are central to the etiologic workup, achieving diagnostic yields of 60-65%. The most commonly identified genetic causes include STXBP1, KCNQ2, and SCN2A variants. Outcomes are poor overall and strongly etiology-dependent: vitamin-responsive disorders carry a substantially more favorable prognosis, whereas mortality reaches 25% in genetic cohorts. Genotype-guided pharmacotherapy is now applicable to a clinically meaningful subset of patients, with sodium channel blockers, potassium channel openers, and emerging antisense oligonucleotide therapies representing important therapeutic advances. Gene therapy trials are underway but have encountered early safety signals, underscoring the vulnerability of this population. Critical unmet needs include earlier molecular diagnosis, precision therapies targeting developmental outcomes beyond seizure control, and prospective international registries to characterize the long-term natural history of EIDEE.
This critical narrative review synthesises evidence on the clinical features, aetiologies, and therapeutic options for these syndromes, and evaluates the strength, consistency, and limitations of that evidence rather than cataloguing individual studies.
S. Bittmann, E. Luchter, Elena Moschüring-Alieva· Asian Journal of Pediatric R...· 0 citations
Early-onset epilepsy in infancy exhibits heterogeneous features and the ILAE framework facilitates a systematic diagnostic approach and supports clinical management in pediatric patients.
BACKGROUND
Epilepsy of infancy with migrating focal seizures (EIMFS) is among the most severe developmental and epileptic encephalopathies (DEEs), marked by intractable multifocal seizures migrating across both hemispheres, profound developmental arrest, and high early mortality. Advances in next-generation sequencing have revealed a heterogeneous genetic architecture dominated by KCNT1 gain-of-function variants across more than 30 implicated genes, creating opportunities for precision therapeutics.
OBJECTIVE
To systematically map published evidence on the clinical, electrophysiological, neuroimaging, genetic, and therapeutic landscape of EIMFS, and to delineate critical knowledge gaps and future research priorities.
METHODS
A scoping review was conducted following the Arksey and O'Malley framework, searching PubMed, Ovid MEDLINE, Embase, Cochrane Library/CENTRAL, and ClinicalTrials.gov.
RESULTS
Of 643 articles screened, 89 met inclusion criteria. Beyond confirmation of the canonical electroclinical phenotype, several gaps emerged: neonatal versus post-neonatal onset stratification by genetic etiology remains largely uncharacterized; genotype-specific EEG biomarkers are lacking except for a single small KCNT1 study; and the clinical significance of atypical EEG features-including burst suppression and hypsarrhythmia-is undefined. Neuroimaging literature documents progressive cerebral atrophy and myelination abnormalities without quantitative volumetry, diffusion tractography markers, or attribution to seizure burden, medication effects, or underlying etiology. Genetic diagnostic yield was 70-80%, with KCNT1 accounting for 30-50% of solved cases; however, genotype-outcome stratification is limited. Seizures were broadly refractory; potassium bromide, ketogenic diet, cannabidiol, and quinidine (in KCNT1-confirmed cases) showed partial efficacy. Emerging precision approaches include sodium channel blockers for SCN2A gain-of-function variants, novel small molecules, fluoxetine, antisense oligonucleotides, and divalent siRNA targeting KCNT1. Systemic-to-pulmonary collateral circulation causing severe cardiopulmonary complications was reported across multiple cases, yet no consensus screening protocol exists.
CONCLUSIONS
EIMFS remains one of the most refractory epilepsy syndromes of infancy. Precision genetic diagnosis is essential to guide targeted therapy. International collaborative registries, standardized outcome measures, genotype-stratified biomarker studies, and rapid point-of-care genomic testing are urgently needed to advance evidence-based care for this highly vulnerable population.
Comprehensive care extends beyond seizure management and includes addressing developmental, educational, and psychosocial needs, and a multidisciplinary, family-centred approach involving neurologists, dietitians, psychologists, and educators is essential.
Jayesh S. Patil, Hitendra S. Chaudhari, S. Pawar et al.· Research and reviews : a jou...· 0 citations
This review examines the evolving landscape of pediatric OLE, highlighting the shift from syndromic to etiological classification and management strategies and the need to monitor cognitive comorbidities and syndrome evolution.
Preeti Srivastava, D. Nag, Shikha Swaroop et al.· World Journal of Clinical Pe...· 0 citations
BACKGROUND
The traditional distinction between syndromic and nonsyndromic craniosynostosis has guided clinical management, but recent genomic advances suggest these categories represent a continuous spectrum rather than discrete entities. Data on genetic etiologies and long-term neurodevelopmental outcomes in Asian populations remain limited.
METHODS
The authors conducted a retrospective cohort study of 68 consecutive children diagnosed with craniosynostosis at a single tertiary center between January 2011 and November 2025. Genetic testing included whole-genome/whole-exome sequencing, targeted next-generation sequencing panels, and chromosomal microarray analysis (CMA). Neurodevelopmental assessments employed the Bayley Scales of Infant Development-III, Social Maturity Scale, Wechsler Intelligence Scales, and Beery-Buktenica Developmental Test of Visual-Motor Integration. Neurodevelopmental disorder (NDD) was defined as the presence of intellectual disability, autism spectrum disorder, or developmental language disorder; a secondary definition additionally included attention-deficit/hyperactivity disorder (ADHD).
RESULTS
Of 68 patients (40 males, 28 females), 39 (57.4%) underwent genetic testing, with pathogenic or likely pathogenic (P/LP) variants identified in 11 (28.2%; genetic-positive group). Identified variants involved chromatin modifiers (DNMT3A, NSD1, KMT2A), transcription factors (TCF12, SOX5), a signaling kinase (TAOK1), and a post-transcriptional regulator (TNRC6B); CMA additionally revealed pathogenic copy number variants (10q26.13-q26.3 deletion, 16p11.2 duplication, 15q11.2-q13.1 duplication, 2q37 deletion). In the primary analysis, NDD was identified in 8 of 11 patients (72.7%) in the genetic-positive group versus 10 of 28 (35.7%) in the genetic-negative group [P = 0.072; odds ratio (OR) 4.80, 95% confidence interval (CI) 1.03-22.29]. In the secondary analysis, including ADHD, NDD was significantly more prevalent in the genetic-positive group (9/11, 81.8% versus 11/28, 39.3%; P = 0.031; OR 6.95, 95% CI 1.26-38.44).
CONCLUSIONS
Comprehensive genetic testing yielded P/LP variants in 28.2% of tested craniosynostosis patients, revealing diverse molecular etiologies. Neurodevelopmental impairment was common and occurred even in genetically negative patients, supporting broad genetic evaluation together with systematic developmental surveillance for all affected children, independent of syndromic classification.
LEVEL OF EVIDENCE
Level III-Retrospective comparative study.
Sunyoung Joo, Jeon-Woong Kang, Si Won Yang et al.· The Journal of craniofacial...· 0 citations