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Since its first clinical description (on his son) by William James West (1793–1848) in 1841, and the definition of the classical triad of (1) infantile spasms; (2) hypsarrhythmia, and (3) developmental arrest or regression as "West syndrome", new and relevant advances have been recorded in this uncommon disorder. New approaches include terminology of clinical spasms (e.g., infantile (IS) vs. epileptic spasms (ES)), variety of clinical and electroencephalographic (EEG) features (e.g., typical ictal phenomena without EEG abnormalities), burden of developmental delay, spectrum of associated genetic abnormalities, pathogenesis, treatment options, and related outcome and prognosis. Aside the classical manifestations, IS or ES may present with atypical electroclinical phenotypes (e.g., subtle spasms; modified hypsarrhythmia) and may have their onset outside infancy. An increasing number of genes, proteins, and signaling pathways play crucial roles in the pathogenesis. This condition is currently regarded as a spectrum of disorders: the so-called infantile spasm syndrome (ISs), in association with other causal factors, including structural, infectious, metabolic, syndromic, and immunologic events, all acting on a genetic predisposing background. Hormonal therapy and ketogenic diet are widely used also in combination with (classical and recent) pharmacological drugs. Biologically targeted and gene therapies are increasingly studied. The present narrative review searched in seven electronic databases (primary MeSH terms/keywords included West syndrome, infantile spasms and infantile spasms syndrome and were coupled to 25 secondary clinical, EEG, therapeutic, outcomes, and associated conditions terms) including MEDLINE, Embase, Cochrane Central, Web of Sciences, Pubmed, Scopus, and OMIM to highlight the past knowledge and more recent advances. [ABSTRACT FROM AUTHOR]

The current spectrum of disorders associated to clinical spasms with onset in infancy is wider than previously thought; accordingly, its terminology has changed. Nowadays, the term Infantile spasms syndrome ( ISs ) defines an epileptic syndrome occurring in children younger than 1 year (rarely older than 2 years), with clinical (epileptic: i.e., associated to an epileptiform EEG) spasms usually occurring in clusters whose most characteristic EEG finding is hypsarrhythmia [the spasms are often associated with developmental arrest or regression]. The term West syndrome ( WS ) refers to a form (a subset) of ISs, characterised by the combination of clustered spasms and hypsarrhythmia on an EEG and delayed brain development or regression [currently, it is no longer required that delayed development occur before the onset of spasms]. Less usually, spasms may occur singly rather than in clusters [ infantile spasms single-spasm variant ( ISSV )], hypsarrhythmia can be (incidentally) recorded without any evidence of clinical spasms [ hypsarrhythmia without infantile spasms ( HWIS )] or typical clinical spasms may manifest in absence of hypsarrhythmia [ infantile spasms without hypsarrhythmia (I SW) ]. There is a growing evidence that ISs and related phenotypes may result, besides from acquired events, from disturbances in key genetic pathways of brain development: specifically, in the gene regulatory network of GABAergic forebrain dorsal–ventral development, and abnormalities in molecules expressed at the synapse. Children with these genetic associations also have phenotypes beyond epilepsy, including dysmorphic features, autism, movement disorders and systemic malformations. The prognosis depends on: (a) the cause, which gives origin to the attacks (the complex malformation forms being more severe); (b) the EEG pattern(s); (c) the appearance of seizures prior to the spasms; and (d) the rapid response to treatment. Currently, the first-line treatment includes the adrenocorticotropic hormone ACTH and vigabatrin. In the near future the gold standard could be the development of new therapies that target specific pathways of pathogenesis. In this article we review the past and growing number of clinical, genetic, molecular and therapeutic discoveries on this expanding topic. [ABSTRACT FROM AUTHOR]

Abstract: Ohtahara syndrome or Early Infantile Epileptic Encephalopathy (EIEE) with Suppression-Burst, is the most severe and the earliest developing age-related epileptic encephalopathy. Clinically, the syndrome is characterized by early onset tonic spasms associated with a severe and continuous pattern of burst activity. It is a debilitating and early progressive neurological disorder, resulting in intractable seizures and severe mental retardation. Specific mutations in at least four genes (whose protein products are essential in lower brain’s neuronal and interneuronal functions, including mitochondrial respiratory chains have been identified in unrelated individuals with EIEE and include: (a) the ARX (aristaless-related) homeobox gene at Xp22.13 (EIEE-1 variant); (b) the CDKL5 (SYK9) gene at Xp22 (EIEE-2 variant); (c) the SLC25A22 (GC1) gene at 11p15.5 (EIEE-3 variant); and (d) the Stxbp1 (MUNC18-1) gene at 9q34-1 (EIEE-4 variant). A yet unresolved issue involves the relationship between early myoclonic encephalopathy (EME–ErbB4 mutations) versus the EIEE spectrum of disorders. [Copyright &y& Elsevier]

Background: At the onset, differentiation between abnormal non-epileptic movements, and epileptic seizures presenting in early life is difficult as is clinical diagnosis and prognostic evaluation of the various seizure disorders presenting at this age. Seizures starting in the first year of life including the neonatal period might have a favorable course, such as in infants presenting with benign familial neonatal epilepsy, febrile seizures simplex or acute symptomatic seizures. However, in some cases, the onset of seizures at birth or in the first months of life have a dramatic evolution with severe cerebral impairment. Seizure disorders starting in early life include the "epileptic encephalopathies", a group of conditions characterized by drug resistant seizures, delayed developmental skills, and intellective disability. This group of disorders includes early infantile epileptic encephalopathy also known as Ohtahara syndrome, early myoclonic encephalopathy, epilepsy of infancy with migrating focal seizures, infantile spasms syndrome (also known as West syndrome), severe myoclonic epilepsy in infancy (also known as Dravet syndrome) and, myoclonic encephalopathies in non-progressive disorder. Here we report on seizures manifesting in the first year of life including the neonatal period. Conditions with a benign course, and those with severe evolution are presented. At this early age, clinical identification of seizures, distinction of each of these disorders, type of treatment and prognosis is particularly challenging. The aim of this report is to present the clinical manifestations of each of these disorders and provide an updated review of the conditions associated with seizures in the first year of life. [ABSTRACT FROM AUTHOR]

Purpose: Mutation analysis of the SCN1B, SCN1A and GABRG2 genes in children affected by Genetic (Generalised) Epilepsy with Febrile Seizures plus (GEFS) and their affected and some unaffected family members, coming from a restricted geographic area, was performed. Methods: Eight GEFS families (58 members) diagnosed according to current GEFS criteria were studied. Results: A heterozygous point mutation A2336G was detected in exon 13 of the SCNA1 gene in three affected members of one family but not in their unaffected relatives; a novel Ile1944Thr mutation was located within the intracellular C-terminal region of the SCNA1 gene in the proband and his healthy father in a second family. In the former family, the proband had dysmorphic features including large forehead, large nasal bridge, pointed nasal tip, triangular nostrils, deep nasolabial folds, thin upper lips with large mouth, congenital gingival hyperplasia with wide gingiva and mental retardation, abnormalities not previously listed in the clinical spectrum of GEFS. Conclusions: Our study confirms that just a few GEFS families have mutations in the five genes classically known and reinforces the genetic and also the phenotypic variability of GEFS featuring clinical manifestations. Question rises whether the cognitive problems seen in two siblings and dysmorphic features in one of them may be related to the channelopathy as it occurs in other well-known ion channel disorders. [ABSTRACT FROM AUTHOR]

Summary: Purpose: To describe the clinical and electroencephalographic (EEG) features of reflex myoclonic epilepsy in infancy (RMEI) and long-term cognitive outcome. Methods: We enrolled 31 children from 16 neuropediatric centres in Italy, who underwent clinical and video-EEG evaluation. Cognitive assessment was performed in all patients using standardized psychometric tests. Results: The age at onset ranged from 3 to 24 months of age. Seizures were characterised in all patients by symmetric myoclonic seizures (MS), triggered by sudden unexpected acoustic (38.7%) or tactile stimuli (29%) or both (29%). Spontaneous attacks were reported in 32.2% of the cases. Ictal EEG showed generalized high-amplitude 3Hz polyspike and wave discharges, synchronous with brief rhythmic bursts of electromyographic activity. Patients were re-evaluated after a period of 7.2±5.6 years. The prognosis for seizure control was excellent in all cases and reflex MS disappeared spontaneously or after valproate treatment. The cognitive outcome was excellent in 90.3% of children. Conclusions: RMEI appears to be a variety of idiopathic generalized epilepsy with specific features that occurs in developmentally normal children. [Copyright &y& Elsevier]

There is no agreement on the prevalence, natural history and outcome of infantile spasms (IS) in neurofibromatosis type 1 (NF1). By contrast, its prevalence and outcome are well characterised in the setting of other neurocutaneous disorders (e.g. tuberous sclerosis). The aim of the present study was to try to establish a genotype–phenotype correlation in IS in the setting of NF1. A retrospective (years 1990–2000) and prospective (years 2000–2006) study in three paediatric centres in Italy were taken as referral populations for: (1) children with NF1 and (2) neurological problems in childhood. Ten NF1 patients have had IS. The calculated population-based: (1) prevalence of IS in NF1 (0.76%) was higher than the reported frequency of IS in the general population (0.02–0.05%) and (2) frequency of NF1 in the IS series in two out of three centres (0.62–0.90%) was lower than the estimated frequencies in the literature (1.5–3.0%). Patients had psychomotor delay preceding the spasms (50%), symmetrical spasms (50%), typical (80%) and modified (20%) hypsarrhythmia and foci of spikes and waves and a good response to corticosteroid treatment (50%). Outcome was good in 30%. Imaging revealed high-signal foci in atypical locations (sub-cortical and central brain regions). Deoxyribonucleic acid analysis revealed three novel NF1 gene mutations without genotype–phenotype correlation. Even though the combination of IS and NF1 does not seem to be coincidental, it is certainly an unusual event in NF1—rarer than in other neurocutaneous disorders. Spasms in NF1 are not associated with specific genetic defects. [ABSTRACT FROM AUTHOR]

The prevalence and outcome of the most frequent type of epilepsy in infancy–infantile spasms (IS)—are well characterized in the setting of most neurocutaneous disorders. By contrast, still there is no study describing the natural history of IS in the setting of Sturge–Weber syndrome (SWS). Two patients with SWS and IS were identified in our series and five in the literature. The aim of study is to evaluate the clinical, electroencephalographic (EEG) and imaging features of our cases and to compare our cases with those described in the literature. IS in the setting of SWS is an uncommon but possible event (2/19 patients seen over 13 years in our institutions). We confirmed the correlation between IS and severity of SWS cutaneous and neural (extension of leptomeningeal capillary malformation) phenotype. IS in SWS seems to be atypical both from a clinical viewpoint (they are asymmetric) and from a laboratory viewpoint (EEG is not classically hypsarrhythmic). [ABSTRACT FROM AUTHOR]