Infantile spasms

Diagnosis and management of infantile epileptic spasms syndrome (IESS) in Gulf Cooperation Council (GCC) countries: Expert consensus statement

Despite the availability of international recommendations for the management of Infantile Epileptic Spasms Syndrome (IESS), there is a lack of recommendations adapted to the local context of clinical practice of pediatric neurology in the Gulf Cooperation Council (GCC) countries. By an initiative from the Saudi Pediatric Neurology Society (SPNS), a literature review was performed and an expert panel comprised of 13 pediatric neurologists from all GCC countries (Saudi Arabia, Kuwait, Bahrain, Oman, Qatar, and the United Arab Emirates) was subsequently convened to discuss all issues related to the management and diagnosis practices of IESS in the GCC. The overall aim of this consensus document was to develop practical recommendations to support the care of patients with IESS in the GCC and to reflect on how clinical management approaches compare with those adopted internationally.

Early-Life Epilepsies

Epilepsies are a diverse group of neurological disorders characterized by recurrent seizures. One-third of epilepsies are refractory to standard antiseizure medications. Epilepsy incidence is age-dependent with high incidence in neonates and infants. Epilepsy syndromes are classified based on clinical, electrographic, neuroimaging, age-dependent features of onset and the possibility of remission. Advances in genetic testing technology and improved access to clinical genetic testing, including whole exome sequencing, have facilitated a fundamental shift in gene discovery of monogenetic and polygenetic epilepsy, leading to precision medicine therapy and improved outcomes. Here, we review the self-limited epilepsy syndromes and developmental and epileptic encephalopathies that begin in the neonatal-infantile period with an emphasis on genetic etiology and the shifting landscape of treatment options based on genetic findings. [Pediatr Ann. 2023;52(10):e381-e387.].

Clinical profile, treatment modalities, and outcomes in patients with infantile spasms: A retrospective study from the United Arab of Emirates (UAE)

BACKGROUND

Infantile spasms (IS) are an epileptic encephalopathy where the prognosis is generally poor, with most patients exhibiting psychomotor retardation or intractable epilepsy. However, it is claimed that early and aggressive treatment is related to better response rate and outcome, especially in patients with idiopathic IS.

OBJECTIVE

To investigate different treatment modalities and outcomes in patients with IS attending a pediatric neurology clinic at a specialized neurology center in Abu Dhabi, United Arab Emirates.

METHODS

Retrospective chart review was done for detailed history, demographic data, etiology, neuro-diagnostic workup, treatment modalities, and the outcomes for all patients diagnosed with IS from September 2014 to September 2019.

RESULTS

Three treatment modalities were identified as 1st line- Prednisolone United Kingdom Infantile Spasms Study (UKISS) (N = 15, 46.8%), Anti-Seizure Medications (ASMs) (N = 12, 37.5%), and Vigabatrin (N = 5, 15.6%). The complete response rate to Vigabatrin as a 1st line treatment showed the highest statistical significance (X² = 7.34, p = 0.007). Patients with idiopathic IS showed a comparable response to treatment to those with symptomatic IS. Additional response to 2nd line treatment with Prednisolone UKISS protocol (25%) and Vigabatrin (15%) was noted in patients who showed partial or no response to the 1st line treatment. None of our patients received Adrenocorticotropic Hormone as treatment. All patients with desirable final outcomes were with idiopathic IS and none were symptomatic.

CONCLUSION

More than a third of our patients showed poor treatment response whenever they were not offered treatment according to the current available protocols. This indicates an urgent need for having a unified treatment protocol that takes into consideration the availability of medications, professional expertise as well as diagnostic workup outside major tertiary care centers in our region.

Efficacy of Ketogenic Diet for Infantile Spasms in Chinese Patients With or Without Monogenic Etiology

OBJECTIVE

The aim of this study was to evaluate the efficacy of the ketogenic diet (KD) for infantile spasms (IS) in patients with and without different causative genetic mutations.

METHODS

We retrospectively evaluated the data of 119 infants with IS who underwent whole-exome sequencing (WES) before KD treatment. The KD efficacy was analyzed at the 16th week after initiation. Patients showing ≥ 50% seizure reduction from baseline and/or the disappeared hypsarrhythmia were considered as the responders. Chi-squared tests or two-sided Fisher's exact tests were performed for categorical data and Mann-Whitney U-tests for non-parametric and continuous data.

RESULTS

The responder rate to KD in 119 patients was 47.90%. Six different causative monogenic mutations were identified in 32 (26.89%) patients with IS, including CDKL5 (n = 8), ALG13 (n = 3), KCNT1 (n = 8), SLC35A2 (n = 5), PCDH19 (n = 4), and STXBP1 (n = 4). Patients with CDKL5 mutations showed a significantly better response to KD (87.50%) than patients without CDKL5 mutations (p = 0.03). Seven of eight patients with CDKL5 mutations were responders, including five mutations located in functional motifs, and two mutations in the catalytic domain.

CONCLUSION

KD therapy was effective in infants with IS. Patients with CDKL5 mutations might have a better response to KD treatment.

Cardiometabolic outcomes in children and adolescents with West syndrome

BACKGROUND

West syndrome is a convulsive disorder of infancy with unique seizures and a characteristic background electroencephalograph pattern. Adrenocorticotropic hormone (ACTH) is effective in spasm cessation, yet metabolic consequences of this therapeutic agent in childhood have not been published.

METHODS

In this observational study we explored the cardiometabolic outcomes of 117 children with West syndrome (78 ACTH-treated and 39 non-ACTH-treated) monitored at a single medical center from 1995 to 2019 (median follow-up 7.2 years). Outcomes included the prevalence of cardiometabolic derangements (obesity, hypertension, and dyslipidemia) during infancy (< 2 years), early childhood (2-6 years), and childhood/adolescence (6-18 years).

RESULTS

The rates of metabolic derangements during infancy in the West syndrome cohort were high compared to childhood/adolescence (obesity 27.3 % vs. 3.3 %, [p = 0.010], diastolic hypertension 48.8 % vs. 5.1 % [p < 0.001], hypertriglyceridemia 71 % vs. 40 % [p = 0.008], low high-density lipoprotein cholesterol [HDL-c] 54.2 % vs. 12.9 % [p = 0.001], and elevated triglycerides/HDL-c ratios 62.5 % vs. 12.9 % [p < 0.001]). The proportion of systolic and/or diastolic blood pressure levels categorized as hypertensive was 58.5 % during infancy, 48.1 % during early childhood, and 26.3 % during childhood/adolescence. ACTH-treated patients had higher weight and weight-to-length z-scores and higher triglyceride levels during infancy compared to non-ACTH-treated patients (p = 0.008, p = 0.001, and p = 0.037, respectively), and higher triglyceride levels during early childhood (p = 0.050), with no significant group differences during childhood/adolescence.

CONCLUSIONS

Children with West syndrome apparently have an increased prevalence of cardiometabolic derangements more pronounced in infants and in ACTH-treated patients. These findings highlight the need to monitor these children for cardiometabolic derangements, even though these cardiometabolic abnormalities are transitory and tend to decrease with time. The health implications of cardiometabolic derangements during critical windows of growth and development warrant further investigation.

Monitoring the frequency and duration of epileptic seizures: "A journey through time"

Seizure monitoring plays an undeniably important role in diagnosing and managing epileptic seizures. Establishing the frequency and duration of seizures is crucial for assessing the burden of this chronic neurological disease, selecting treatment methods, determining how frequently these methods are applied, and informing short and long-term therapeutic decisions. Over the years, seizure monitoring tools and methods have evolved and become increasingly sophisticated; from home seizure diaries to EEG monitoring to cutting-edge responsive neurostimulation systems. In this article, the various methods of seizure monitoring are reviewed.

Cognitive outcome in children with infantile spasms using a standardized treatment protocol. A five-year longitudinal study

AIM

To evaluate the long-term developmental trajectory of children with infantile spasms (IS) and identify the clinical protective and risk factors associated with their cognitive outcome.

METHODS

We analyzed the five-year follow-up results of 41 children (13 female) from the previously published cohort (n = 68) recruited in a multicenter randomized controlled trial for 2-years, examining the effect of an adjunctive therapy (Flunarizine) on standardized IS treatment. The children were subsequently monitored in an open-label study for additional 3 years.  The Vineland Adaptive Behavior Scale, second edition, and either the Stanford-Binet Intelligence Scale, Fifth Edition (SB5) or the Bayley Scales of Infant Development, second edition (BSID-II) were used as cognitive outcome measures.

RESULTS

Etiology was the strongest predictor of outcome. Children with no identified etiology (NIE) showed a progressive improvement of cognitive functions, mostly occurring between 2 and 5 years post-diagnosis.  Conversely, symptomatic etiology was predictive of poorer cognitive outcome. Developmental delay, other seizure types (before and after IS diagnosis), and persistent electroencephalographic abnormalities following treatment were predictive of poor cognitive outcome.

INTERPRETATION

Given the 5-year cognitive improvement, children with IS should undergo a developmental assessment before school entry. Factors influencing their cognitive outcome emphasize the importance of thorough investigation and evidence-based treatment.

Early developmental electroencephalography abnormalities, neonatal seizures, and induced spasms in a mouse model of tuberous sclerosis complex

OBJECTIVE

Tuberous sclerosis complex (TSC) is one of the most common genetic causes of epilepsy. Seizures in TSC typically first present in infancy or early childhood, including focal seizures and infantile spasms. Infantile spasms in TSC are particularly characteristic in its strong responsiveness to vigabatrin. Although a number of mouse models of epilepsy in TSC have been described, there are very limited electroencephalographic (EEG) or seizure data during the preweanling neonatal and infantile-equivalent mouse periods. Tsc1^GFAP CKO mice are a well-characterized mouse model of epilepsy in TSC, but whether these mice have seizures during early development has not been documented. The objective of this study was to determine whether preweanling Tsc1^GFAP CKO mice have developmental EEG abnormalities or seizures, including spasms.

METHODS

Longitudinal video-EEG and electromyographic recordings were performed serially on Tsc1^GFAP CKO and control mice from postnatal days 9-21 and analyzed for EEG background abnormalities, sleep-wake vigilance states, and spontaneous seizures. Spasms were also induced with varying doses of N-methyl-D-aspartate (NMDA).

RESULTS

The interictal EEG of Tsc1^GFAP CKO mice had excessive discontinuity and slowing, suggesting a delayed developmental progression compared with control mice. Tsc1^GFAP CKO mice also had increased vigilance state transitions and fragmentation. Tsc1^GFAP CKO mice had spontaneous focal seizures in the early neonatal period and a reduced threshold for NMDA-induced spasms, but no spontaneous spasms were observed.

SIGNIFICANCE

Neonatal Tsc1^GFAP CKO mice recapitulate early developmental aspects of EEG abnormalities, focal seizures, and an increased propensity for spasms. This mouse model may be useful for early mechanistic and therapeutic studies of epileptogenesis in TSC.

Reliability of Handheld Optical Coherence Tomography in Children Younger Than Three Years of Age Undergoing Vigabatrin Treatment for Childhood Epilepsy

Purpose

Vigabatrin-associated retinal toxicity manifests as reduction in the clinical electroretinogram and retinal nerve fiber layer (RNFL) thinning. This observational investigation of RNFL thickness in young vigabatrin-treated children was to identify intravisit and intervisit reliabilities of peripapillary RNFL thickness measurements performed with Envisu (optical coherence tomography) OCT. Secondarily, a longitudinal assessment investigated the presence and extent of RNFL thinning.

Methods

We measured the handheld OCT in sedated children to evaluate the RNFL thickness using segmentation software. Intraclass correlation coefficient (ICC) statistics identified intravisit and intervisit reliabilities for RNFL thickness.

Results

Twenty-nine children (10.1 ± 6.0 months old) underwent handheld optical coherence tomography (OCT). Fourteen of these completed follow-up assessments. Intravisit reliability was good for the right eye (ICCs = 0.82-0.98) and the left eye (ICCs = 0.75-0.89) for each of the 4 retinal quadrants. Inter-visit ICCs for each of the 4 retinal quadrants were good (ICC = 0.82-0.98). There was no consistent change in RNFL thickness longitudinally.

Conclusions

In this pediatric cohort, RNFL thickness measures using handheld OCT provided good reliability within a single visit and between consecutive visits supporting its use as an adjunctive tool in the clinical setting. Further long-term follow-up is required to understand RNFL thickness changes in this specific population and its association with vigabatrin toxicity.

Translational Relevance

The findings of good reliability and clinical feasibility would provide an opportunity for the handheld OCT to monitor reliably for vigabatrin-associated retinal toxicity in children who often show noncompliance to traditional testing approaches.

Etiologic classification of infantile spasms using positron emission/magnetic resonance imaging and the efficacy of adrenocorticotropic hormone therapy

PURPOSE

The aim of this study was to investigate if the etiologic classification of infantile spasm (IS) using positron emission tomography/magnetic resonance imaging (PET/MR) is feasible. Based on the classified etiologic groups, we further evaluated the efficacy of adrenocorticotropic hormone (ACTH) therapy in different IS groups.

MATERIALS AND METHODS

One hundred fifty-five children diagnosed with IS were included in this study. A qualitative assessment of the PET/MR images was performed. The abnormal lesions localized with both MR and PET images were considered to be epileptic foci, and the patients with these lesions were classified into the structural-metabolic group. For the remaining patients, quantitative analyses were further performed on whole-brain T1-weighted (T1WI) and PET images, based on the asymmetry index of bilateral volumes and metabolic quantifications. Patients with asymmetry indices above a certain threshold (15%) were classified into the structural-metabolic group. The patients without positive finding from either qualitative or quantitative analyses were assigned to the unknown etiology group. The efficacy of ACTH therapy was evaluated in the different IS groups.

RESULTS

Among the 155 children with IS, 18 genetic cases were first diagnosed by the genetic testing. In the remaining 137 cases, 49 cases were identified with structural-metabolic etiology using qualitative PET/MR assessments. Fifty-two cases were newly diagnosed with quantitative analysis. The remaining 36 cases were classified into the unknown etiology group. The efficacy of ACTH therapy was statistically different for the different etiology groups (p < 0.001). The respective efficacy rates for the genetic, qualitative structural-metabolic, quantitative structural-metabolic, and unknown etiology groups were 27.8% (5/18), 30.61% (15/49), 34.62% (18/52), and 72.22% (26/36), respectively.

CONCLUSIONS

The combination of PET and MR provides additional diagnostic information for IS. Quantitative analysis can further improve patient etiologic classifications and the predication of therapy efficacies.

Impact of therapeutic hypothermia on infantile spasms: an observational cohort study

AIM

To establish the incidence of infantile spasms in children in the southern region of the Republic of Ireland and to compare the incidence of infantile spasms before and after the introduction of therapeutic hypothermia in infants with hypoxic-ischemic encephalopathy (HIE).

METHOD

Children born between 2003 and 2015 and diagnosed with infantile spasms (epileptic spasms with or without hypsarrhythmia) in the first 2 years of life were identified through audits of electroencephalography reports and paediatric neurology patient lists. Data on live births were obtained from the regional hospital statistics databases. Medical charts of infantile spasm cases were reviewed for demographic information, diagnostic workup results, treatment response, disease course, and developmental outcome.

RESULTS

Forty-two infants with infantile spasms were identified. The cumulative incidence of infantile spasms up to the age of 2 years was 4.01 per 10 000 live births. Difference due to sex was minimal (22 males, 20 females) and most infants were delivered at or near term with gestational ages ranging between 30.0 and 41.8 weeks (median [interquartile range] 39.6wks [38.1-40.0wks]). The aetiology for infantile spasms was identified in almost two-thirds of cases, with HIE being the single most common cause (n=7). Other causes included chromosomal and monogenetic abnormalities (n=8). Infantile spasms occurred in moderate and severe grades of HIE, with a significantly higher incidence in those with severe HIE (p=0.029). Infants with severe HIE who did not receive therapeutic hypothermia were six times more likely to develop infantile spasms compared to those who did, but the difference was not statistically significant (4 out of 16 vs 1 out of 24, p=0.138).

INTERPRETATION

This study provides detailed information about infantile spasms before and after the introduction of therapeutic hypothermia. HIE severity is a risk factor for the development of infantile spasms. The introduction of therapeutic hypothermia may have had an impact, but the effect was hard to ascertain in this cohort due to the small number of infants.

WHAT THIS PAPER ADDS

The incidence of infantile spasms and patient characteristics in the southern region of the Republic of Ireland is similar to internationally published data. None of the infants with a history of mild hypoxic-ischemic encephalopathy (HIE) developed infantile spasms. The risk of infantile spasms was higher in infants with severe HIE. Infantile spasms were more frequent in infants with severe HIE not treated with therapeutic hypothermia.

Neurodevelopmental outcomes of the West syndrome in pediatric patients: The first report from the Middle-East

BACKGROUND

This study aimed to investigate the clinical characteristics and neurodevelopmental outcomes of children with West syndrome (WS) by using the Bayley-III scale of infant development, as the first report from the Middle-East.

METHODS

Between January 2013 and February 2016, we prospectively enrolled 67 consecutive patients with a confirmed diagnosis of WS from Isfahan, Iran. Cognition, language and motor outcomes of the studied subjects were evaluated with the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III).

RESULTS

Overall, 67 cases, including 34 (50.7%) boys and 33 (49.3%) girls (a male/female ratio of 1.03), were enrolled for the study. The mean age was 26.7 ± 12.9 months. Among the subjects, 50 (74.6%) patients had symptomatic WS, and 17 (25.4%) patients had cryptogenic WS. "Severe delay" was found in 76.9% of the patients regarding cognitive evaluation, 67.7% for language and communication abilities, and, 81.5% for motor function. The patients with cryptogenic WS were significantly more likely to have more favorable outcomes in motor (p = 0.035), cognitive (p = 0.035) and receptive language (p = 0.043) in comparison to those who had symptomatic WS. The patients with controlled seizures were significantly more likely to have more favorable outcomes in motor (p = 0.027) and cognition (p = 0.011) as compared to those with uncontrolled seizures.

CONCLUSION

WS was associated with poor neurodevelopmental outcome in our study. Severe developmental delay was associated with two major factors: (i) presence of a specific underlying abnormality (symptomatic WS) and(ii) persistent seizures as a result of the former.

Bridging the childhood epilepsy treatment gap in northern Nigeria (BRIDGE): Rationale and design of pre-clinical trial studies

Epilepsy is the most common serious childhood neurological disorder. In the low- and middle-income countries (LMICs) of Africa, children with epilepsy suffer increased morbidity and mortality compared to their counterparts in high-income countries, and the majority do not receive treatment - the childhood epilepsy treatment gap. Reports of the childhood epilepsy treatment gap in Africa are likely underestimates; most surveys do not include several common childhood seizure types, including most types of non-convulsive epilepsy. Efforts to scale up childhood epilepsy care services in the LMICs of Africa must contend with a shortage of physicians and diagnostic technology [e.g., electroencephalograms (EEGs)]. One pragmatic solution is to integrate epilepsy care into primary care by task-shifting to community health extension workers. The aims of this project (BRIDGE) are to: 1) train, develop, and pilot task-shifted epilepsy care teams; 2) develop and pilot innovative childhood epilepsy screening and diagnostic paradigms adapted to the local Hausa language/culture in Kano, northern Nigeria; and, 3) quantify and map the childhood epilepsy treatment gap, using geographic information systems (GIS), to target limited resources to areas of greatest need. Task-shifted teams will diagnose and manage childhood epilepsy using an innovative epilepsy screening tools and diagnostic and management paradigms in environments with limited EEG access. If validated and demonstrated efficacious in clinical trials, this project can be taken to scale across broader areas of west Africa's LMICs that share language and culture. BRIDGE has the potential to enhance access to basic childhood epilepsy care and establish the foundation for childhood epilepsy clinical trials in west Africa.

Surgical and developmental outcomes of corpus callosotomy for West syndrome in patients without MRI lesions

OBJECTIVE

This retrospective study was designed to assess the impact of corpus callosotomy (CC) in patients with intractable West syndrome (WS) without lesions on magnetic resonance imaging (MRI).

METHODS

This study involved 56 patients with WS who underwent CC between January 2000 and December 2014. Seizure outcomes and changes in psychomotor development were analyzed.

RESULTS

Mean age at the onset of epilepsy and at the time of CC was 5.1 and 22.6 months, respectively. Mean duration of epilepsy before CC was 17.6 months. Video-electroencephalography (EEG) monitoring showed bilateral ictal and interictal abnormalities before CC. Mean follow-up duration was 36.6 months. At final follow-up, seizure outcomes after CC were seizure-free in 18 patients (32.1%), excellent (E: >80% reduction in seizure frequency) in 15 (26.8%), good (G: >50% reduction) in 10 (17.9%), and poor (P: <50% reduction) in 13 (23.2%). Epileptic spasms (ES) were eliminated in 24 patients (42.9%). However, tonic seizure (TS) outcomes were poor (P < 0.05). Of preoperative predictive factors related to seizure outcome, developmental delay before epilepsy onset correlated with poor outcome (P < 0.05). One year post-CC, 6 patients (10.7%) had no epileptic abnormality on EEG, 19 (33.9%) had lateralized epileptic abnormalities, and 31 (55.4%) had bilateral asynchronous epileptic abnormalities. All patients without epileptic discharge achieved seizure freedom. Fifteen of 19 (78.9%) patients in the lateralized group and 12 of 31 (38.7%) in the bilateral asynchronous group had worthwhile outcomes (F + E). The patterns of EEG changes after CC correlated with seizure outcome (P < 0.01). Progressive declines in developmental quotient were prevented in patients with worthwhile outcomes.

SIGNIFICANCE

CC represents an important therapeutic option for patients with WS without resectable MRI lesions. Transcallosal seizure bilateralization is critical for bilateral ES generation. Early identification of potential CC candidates and surgical intervention are important for better seizure control and cognitive capacity preservation before severe developmental delay development.

West Syndrome: A Review and Guide for Paediatricians

West syndrome (WS), also known as infantile spasms, occurs in infancy with a peak between 4 and 7 months. Spasms, neurodevelopmental regression and hypsarrhythmia on electroencephalogram (EEG) basically define WS. The International League Against Epilepsy commission classifies the aetiologies of WS into genetic, structural, metabolic and unknown. Early diagnosis and a shorter lag time to treatment are essential for the overall outcome of WS patients. These goals are feasible with the addition of brain magnetic resonance imaging (MRI) and genetic and metabolic testing. The present work analysed the medical literature on WS and reports the principal therapeutic protocols of its management. Adrenocorticotropic hormone (ACTH), vigabatrin (VGB) and corticosteroids are the first-line treatments for WS. There is no unique therapeutic protocol for ACTH, but most of the evidence suggests that low doses are as effective as high doses for short-term treatment, which is generally 2 weeks followed by dose tapering. VGB is generally administered at doses from 50 to 150 mg/kg/day, but its related retinal toxicity, which occurs in 21-34% of infants, is most frequently observed when treatment periods last longer than 6 months. Among corticosteroids, a treatment of 14 days of oral prednisolone (40-60 mg/day) has been considered effective and well tolerated. Considering that an early diagnosis and a shorter lag time to treatment are essential for successful outcomes in these patients, further studies on efficacy of the different therapeutic approaches with evaluation of final outcome after cessation of therapy are needed.

Infantile Epileptic Encephalopathy With Multiple Genetic Mutations: How Important are Variants of Undetermined Significance?

The importance of so called variants of undetermined significance in the development of Infantile Epileptic Encephalopathy is discussed and an illustrative case is presented.

Cytotoxic edema at onset in West syndrome of unknown etiology: A longitudinal diffusion tensor imaging study

OBJECTIVE

To clarify longitudinal changes in white matter microstructures from the onset of disease in patients with West syndrome (WS) of unknown etiology.

METHODS

Diffusion tensor imaging (DTI) was prospectively performed at onset and at 12 and 24 months old in 17 children with WS of unknown etiology. DTI was analyzed using tract-based spatial statistics (TBSS) and tract-specific analysis (TSA) of 13 fiber tracts, and fractional anisotropy (FA) and mean diffusivity (MD) were compared with those of 42 age-matched controls. Correlations of FA and MD with developmental quotient (DQ) at age 24 months were analyzed. Multiple comparisons were adjusted for using the false discovery rate (q-value).

RESULTS

TBSS analysis at onset showed higher FA and lower MD in the corpus callosum and brainstem in patients. TSA showed lower MD in bilateral uncinate fasciculi (UF) (right: q < 0.001; left: q = 0.03) at onset in patients. TBSS showed a negative correlation between FA at onset and DQ in the right frontal lobe, whereas FA at 24 months old exhibited a positive correlation with DQ in the diffuse white matter. MD for bilateral UF at 24 months old on TSA correlated positively with DQ (q = 0.04, both).

SIGNIFICANCE

These findings may indicate the existence of cytotoxic edema in the immature white matter and dorsal brainstem at onset, and subsequent alterations in the diffuse white matter in WS of unknown etiology. Microstructural development in the UF might play important roles in cognitive development in WS.

Targeting the Mammalian Target of Rapamycin for Epileptic Encephalopathies and Malformations of Cortical Development

Malformations of cortical development represent a common cause of epileptic encephalopathies and drug-resistant epilepsy in children. As current treatments are often ineffective, new therapeutic targets are needed for epileptic encephalopathies associated with cortical malformations. The mechanistic/mammalian target of rapamycin (mTOR) pathway constitutes a signaling pathway that drives cellular and molecular mechanisms of epileptogenesis in a variety of focal cortical malformations. mTOR inhibitors prevent epilepsy and associated pathogenic mechanisms of epileptogenesis in mouse models of tuberous sclerosis complex and are currently in clinical trials for drug-resistant seizures in these patients. A recent explosion of genetic studies has linked mutations in various genes regulating the mTOR pathway to other cortical malformations, such as focal cortical dysplasia and hemimegalencephaly. Thus, mTOR inhibitors represent promising candidates as novel antiseizure and antiepileptogenic therapies for epilepsy associated with a spectrum of cortical malformations.

The Need for Antiepileptic Drug Chronotherapy to Treat Selected Childhood Epilepsy Syndromes and Avert the Harmful Consequences of Drug Resistance

Antiepileptic drug (AED) chronotherapy involves the delivery of a greater AED dose at the time of greatest seizure susceptibility usually associated with predictable seizure peaks. Although research has proven AED chronotherapy, commonly known as differential dosing, to be safe, well tolerated, and highly effective in managing cyclic seizure patterns in selected childhood epilepsies, conventional, equally divided AED dosing remains the standard of care. Differential dosing is more often applied in the emergency management of acute seizure clustering resulting from drug resistance-a harmful epilepsy-related consequence that affects 30% of children. Moreover, drug resistance is a major risk factor in status epilepticus and sudden, unexpected death in epilepsy. Although these facts should promote the wider use of differential dosing in selected cases, a credible hypothesis is needed that defines the differential dosing strategy and application in cyclic epilepsy and for the greater purpose of preventing harmful outcomes.

Fast oscillation dynamics during hypsarrhythmia as a localization biomarker

Hypsarrhythmia in West syndrome, although hard to define, is characterized by chaotic and disorganized electrical activity of the brain and is often regarded as a generalized EEG pattern without any localization value. Using event-related spectral perturbation (ERSP), we tried to determine the brain dynamics during hypsarrhythmia. Routine 1-h scalp EEGs were retrieved from 31 patients with infantile spasms and 20 age-matched controls. Using the EEGLAB toolbox of MATLAB 2015b, the ERSPs of fast oscillations (FOs; 20-100 Hz) of selected channels were analyzed and compared among groups according to their MRI lesions. FO-ERSP cutoff values for predicting the pathologic foci were estimated. The mean FO-ERSPs across all analyzed electrodes of patients with spasms were significantly higher than those of controls. When the patients were categorized into nonlesional, focal/multifocal, or diffuse lesional groups, the FO-ERSP of patients in the focal/multifocal lesional group was significantly lower than that of those in the nonfocal or diffuse lesional groups. In the focal/multifocal lesional group, seven patients (7/9, 77.8%) showed that the locations of channels with high FO-ERSPs were matched to the pathologic MRI lesions. Thus, the localization of high FO-ERSPs is closely associated with the location of pathologic brain lesions. Further research is required to prove the value of the FO-ERSP as an important quantitative localizing biomarker of West syndrome. NEW & NOTEWORTHY The locations of high fast oscillation-event-related spectral perturbations (FO-ERSPs) are closely associated with brain pathologic lesions, and high FO-ERSPs can be used as a localization biomarker of pathologic brain lesions in patients with hypsarrhythmia. With further validation, FO-ERSP might be useful as a biomarker for the localization of hidden pathologies in conditions with generalized epileptiform activities such as West syndrome.

APC conditional knock-out mouse is a model of infantile spasms with elevated neuronal β-catenin levels, neonatal spasms, and chronic seizures

Infantile spasms (IS) are a catastrophic childhood epilepsy syndrome characterized by flexion-extension spasms during infancy that progress to chronic seizures and cognitive deficits in later life. The molecular causes of IS are poorly defined. Genetic screens of individuals with IS have identified multiple risk genes, several of which are predicted to alter β-catenin pathways. However, evidence linking malfunction of β-catenin pathways and IS is lacking. Here, we show that conditional deletion in mice of the adenomatous polyposis coli gene (APC cKO), the major negative regulator of β-catenin, leads to excessive β-catenin levels and multiple salient features of human IS. Compared with wild-type littermates, neonatal APC cKO mice exhibit flexion-extension motor spasms and abnormal high-amplitude electroencephalographic discharges. Additionally, the frequency of excitatory postsynaptic currents is increased in layer V pyramidal cells, the major output neurons of the cerebral cortex. At adult ages, APC cKOs display spontaneous electroclinical seizures. These data provide the first evidence that malfunctions of APC/β-catenin pathways cause pathophysiological changes consistent with IS. Our findings demonstrate that the APC cKO is a new genetic model of IS, provide novel insights into molecular and functional alterations that can lead to IS, and suggest novel targets for therapeutic intervention.

Mitochondrial translation factors reflect coordination between organelles and cytoplasmic translation via mTOR signaling: Implication in disease

Mitochondria are semi-autonomous organelle possessing their own translation machinery to biosynthesize mitochondrial DNA (mtDNA)-encoded polypeptides, which are the core subunits of oxidative phosphorylation (OXPHOS) complexes. Mitochondrial translation elongation factor 4 (mtEF4) is a key quality control factor in mitochondrial translation (mt-translation) that regulates mitochondrial tRNA translocation and modulates cellular responses by influencing cytoplasmic translation (ct-translation). In addition to mtEF4, mt-translational activators, mitochondrial microRNAs (mitomiRs), and MITRAC have been reported recently as crucial mt-translation regulators. Here, we focus on the novel ways how these factors regulate mt-translation, discuss the main cellular response of mammalian target of rapamycin (mTOR) signalling upon mt-translation defects, and summarize the related human diseases.

Intermittent head drops: the differential spectrum

Intermittent Head Drops are episodic head flexion movements that can occur in a number of conditions. Typically, the term has mainly been related to epileptic episodes, but the spectrum of clinical conditions associated with this feature is wide-ranging even if never discussed in detail. By searching the electronic database, we may find that apart from the epileptic conditions, Intermittent Head Drops have been in fact reported in the setting of movement disorders, sleep disorders and even internal medicine disorders, such as Sandifer syndrome. We render an in-depth description of this characteristic phenomenon in different diseases, describing the clinical clues and neurophysiological patterns that may help the clinician to distinguish between the different settings of occurrence.

Early-onset epileptic encephalopathies and the diagnostic approach to underlying causes

Early-onset epileptic encephalopathies are one of the most severe early onset epilepsies that can lead to progressive psychomotor impairment. These syndromes result from identifiable primary causes, such as structural, neurodegenerative, metabolic, or genetic defects, and an increasing number of novel genetic causes continue to be uncovered. A typical diagnostic approach includes documentation of anamnesis, determination of seizure semiology, electroencephalography, and neuroimaging. If primary biochemical investigations exclude precipitating conditions, a trial with the administration of a vitaminic compound (pyridoxine, pyridoxal-5-phosphate, or folinic acid) can then be initiated regardless of presumptive seizure causes. Patients with unclear etiologies should be considered for a further workup, which should include an evaluation for inherited metabolic defects and genetic analyses. Targeted next-generation sequencing panels showed a high diagnostic yield in patients with epileptic encephalopathy. Mutations associated with the emergence of epileptic encephalopathies can be identified in a targeted fashion by sequencing the most likely candidate genes. Next-generation sequencing technologies offer hope to a large number of patients with cryptogenic encephalopathies and will eventually lead to new therapeutic strategies and more favorable long-term outcomes.

West syndrome caused by homozygous variant in the evolutionary conserved gene encoding the mitochondrial elongation factor GUF1

West syndrome (WS), defined by the triad of infantile spasms, pathognomonic hypsarrhythmia and developmental regression, is a rare epileptic disease affecting about 1:3500 live births. To get better insights on the genetic of this pathology, we exome-sequenced the members of a consanguineous family affected with isolated WS. We identified a homozygous variant (c.1825G>T/p.(Ala609Ser)) in the GUF1 gene in the three affected siblings. GUF1 encodes a protein essential in conditions that counteract faithful protein synthesis: it is able to remobilize stuck ribosomes and transiently inhibit the elongation process to optimize protein synthesis. The variant identified in the WS family changes an alanine residue conserved in all eukaryotic organisms and positioned within the tRNA-binding moiety of this nuclear genome-encoded mitochondrial translational elongation factor. Yeast complementation assays show that the activity of GUF1(A609S) is modified in suboptimal environments. We suggest a new link between improper assembly of respiratory chain complexes and WS.

West syndrome associated with a novel chromosomal anomaly; partial trisomy 8P together with partial monosomy 9P, resulting from a familial unbalanced reciprocal translocation

West syndrome is classified according to the underlying etiology into an acquired West syndrome, a congenital/developmental West syndrome, and West syndrome of unknown etiology. Causes of a congenital/developmental West syndrome are extensive and include chromosomal anomalies. We report on a patient carrying a derivative chromosome originating from the reciprocal unbalanced translocation t (8;9) (p11.2;p22) and presenting with macrocephaly, West syndrome, severe mental motor retardation and hypotonia. As far as we know, this is a new chromosomal anomaly associated with West syndrome.

How should children with West syndrome be efficiently and accurately investigated? Results from the National Infantile Spasms Consortium

OBJECTIVE

To prospectively evaluate the etiology of new-onset infantile spasms and evaluate the yield of genetic and metabolic investigations in those without obvious cause after initial clinical evaluation and magnetic resonance imaging (MRI).

METHODS

Twenty-one U.S. pediatric epilepsy centers prospectively enrolled infants with newly diagnosed West syndrome in a central database. Etiology and investigations performed within 3 months of diagnosis were documented.

RESULTS

From June 2012 to June 2014, a total of 251 infants were enrolled (53% male). A cause was identified in 161 (64.4%) of 250 cases (genetic,14.4%; genetic-structural, 10.0%; structural-congenital, 10.8%; structural-acquired, 22.4%; metabolic, 4.8%; and infectious, 2.0%). An obvious cause was found after initial clinical assessment (history and physical examination) and/or MRI in 138 of 161, whereas further genetic and metabolic studies were revealing in another 23 cases. Of 112 subjects without an obvious cause after initial evaluation and MRI, 81 (72.3%) had undergone genetic testing, which showed a causal abnormality in 23.5% and a variant of unknown significance in 14.8%. Although metabolic studies were done in the majority (serum, 79.5%; urine, 69.6%; and cerebrospinal fluid [CSF], 38.4%), these revealed an etiology in only five cases (4.5%). No correlation was found between type of health insurance (public vs. private) and either genetic or metabolic testing.

SIGNIFICANCE

Clinical evaluation and MRI provide a specific diagnosis in 55% of children presenting with West syndrome. We propose that a cost-effective workup for those without obvious cause after initial clinical evaluation and MRI includes an array comparative genomic hybridization (aCGH) followed by an epilepsy gene panel if the microarray is not definitive, serum lactate, serum amino acids, and urine organic acids.

Infantile spasms syndrome, West syndrome and related phenotypes: what we know in 2013

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 (ISW)]. 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.

Hereditary neurometabolic causes of infantile spasms in 80 children presenting to a tertiary care center

BACKGROUND

Infantile spasms are a devastating infantile epileptic syndrome with multiple etiologies. Hereditary neurometabolic disorders are rarely recognized causes of infantile spasms. The aim of this study was to identify hereditary neurometabolic disorders when they were the cause of infantile spasms in patients presenting to a tertiary care center in Saudi Arabia.

METHODOLOGY

We conducted a retrospective review of children presenting to the Pediatric Department of King Abdulaziz Medical City in Riyadh, Saudi Arabia over a 15-year interval.

RESULTS

Eighty patients with infantile spasms were identified. A hereditary neurometabolic disorder was diagnosed in 10 patients (12.5%). Of these patients, two had a Leigh-like disorder and one patient had each of the following diagnoses: ethylmalonic aciduria, nonketotic hyperglycinemia, hyperinsulinemic hypoglycemia, leukodystrophy, short-chain acyl-coenzyme A dehydrogenase deficiency, molybdenum cofactor deficiency, primary carnitine deficiency, and neonatal hypoglycemia due to panhypopituitarism. This article is the first to report the association of the last three conditions with infantile spasms. Compared with the other etiologies, the hereditary neurometabolic disorder group had a strong history of similar disease in the same family (P = 0.002), and most of the patients were born of consanguineous parents (P = 0.021). In addition, a typical hypsarrhythmia pattern was more common in the hereditary neurometabolic disorder group (P = 0.003). Furthermore, this group had a poor response to therapy (P = 0.04). Otherwise, there were no significant differences regarding the type of spasms, neuroimaging or outcome; however, there was a trend toward poorer outcomes and death in the hereditary neurometabolic disorder group.

CONCLUSION

Hereditary neurometabolic disorders are relatively common causes of infantile spasms in this subpopulation of Saudi patients. An early diagnosis via proper metabolic and genetic testing has significant implications for applying specific treatments and for facilitating proper family counseling.

Generalized epilepsies: immunologic and inflammatory mechanisms

This article focuses on the inflammatory processes in patients with generalized epilepsies. We specifically review the data regarding West, Lennox-Gastaut, and Landau-Kleffner syndromes as they have generalized clinical or electroencephalogram features. There is substantial evidence for a pathogenic implication of immune mechanisms in these epilepsies. Animal models and abnormalities in both cellular and humoral immunity support this hypothesis. They also appear to be particularly responsive to immunomodulatory therapies, which has raised the speculation that an unbalanced immune system may play an important role in the pathophysiology of these epileptic syndromes. In this article, we discuss clinical and experimental data that support the potential implication of immune mediated inflammation and immune response in the mechanism of these entities.

Possessed by evil spirits: a history of seizures in infancy

For 4 millennia, seizures in infancy were believed to be of supranatural origin and were dealt with by incantations, exorcising rituals, and protective amulets. Instead of pursuing scientific research into their causes, gods, devils, mothers, wet nurses, midwives, or obstetricians were blamed. Help from protective gods and patron saints was sought, and amulets against the "evil eye" were recommended by physicians, mostly in the form of necklaces. Infants were despised and hidden away from the community. Among the medical conditions associated with seizures, those most prominent were dentition, gastrointestinal irritation, and "bad" mother's milk. Medical treatment consisted of cutting or rubbing the gums with a hare's brain during dentition, and applying peony or theriac. Even during the 20th century, when laboratory methods, electroencephalography, brain imaging, and powerful pharmaceutical techniques were available, effective treatment evolved empirically rather than systematically.

GABAergic interneuron development and function is modulated by the Tsc1 gene

Tuberous sclerosis complex (TSC) is a genetic disease with severe neurologic and psychiatric manifestations including epilepsy, developmental delay, and autism. Despite much progress in defining abnormal signaling pathways including the contribution of increased mTORC1 signaling, specific abnormalities that underlie the severe neurologic features in TSC remain poorly understood. We hypothesized that epilepsy and autism in TSC result from abnormalities of γ-aminobutyric acidergic (GABAergic) interneurons. To test this hypothesis, we generated conditional knockout mice with selective deletion of the Tsc1 gene in GABAergic interneuron progenitor cells. These interneuron-specific Tsc1 conditional knockout (CKO) mice have impaired growth and decreased survival. Cortical and hippocampal GABAergic interneurons of CKO mice are enlarged and show increased mTORC1 signaling. Total numbers of GABAergic cells are reduced in the cortex with differential reduction of specific GABAergic subtypes. Ectopic clusters of cells with increased mTORC1 signaling are also seen suggesting impaired interneuron migration. The functional consequences of these cellular changes are evident in the decreased seizure threshold on exposure to the proconvulsant flurothyl. These findings support an important role for the Tsc1 gene during GABAergic interneuron development, function, and possibly migration.

Infantile spasms (West syndrome): update and resources for pediatricians and providers to share with parents

BACKGROUND

Infantile spasms (IS; West syndrome) is a severe form of encephalopathy that typically affects infants younger than 2 years old. Pediatricians, pediatric neurologists, and other pediatric health care providers are all potentially key early contacts for families who have an infant with IS. The objective of this article is to assist pediatric health care providers in the detection of the disease and in the counseling and guidance of families who have an infant with IS.

METHODS

Treatment guidelines, consensus reports, and original research studies are reviewed to provide an update regarding the diagnosis and treatment of infants with IS. Web sites were searched for educational and supportive resource content relevant to providers and families of patients with IS.

RESULTS

Early detection of IS and pediatrician referral to a pediatric neurologist for further evaluation and initiation of treatment may improve prognosis. Family education and the establishment of a multidisciplinary continuum of care are important components of care for the majority of patients with IS. The focus of the continuum of care varies across diagnosis, initiation of treatment, and short- and long-term needs. Several on-line educational and supportive resources for families and caregivers of patients with IS were identified.

CONCLUSIONS

Given the possibility of poor developmental outcomes in IS, including the emergence of other seizure disorders and cognitive and developmental problems, early recognition, referral, and treatment of IS are important for optimal patient outcomes. Dissemination of and access to educational and supportive resources for families and caregivers across the lifespan of the child with IS is an urgent need. Pediatric health care providers are well positioned to address these needs.

Coexisting seizures in patients with infantile spasms confirmed by long-term video-electroencephalography monitoring

PURPOSE

We performed this study to evaluate the frequency, types, and ictal electroencephalography (EEG) findings of coexisting seizures in patients with infantile spasms at the onset of spasms. We also evaluated the effect of coexisting seizures on short-term seizure control.

METHODS

We retrospectively reviewed the long-term video-EEG and electronic medical records of 109 patients (58 boys and 51 girls) diagnosed with infantile spasms at the Seoul National University Children's Hospital. Coexisting seizure types were classified according to the International League Against Epilepsy seizure and epilepsy classification. Ictal EEG findings were also reviewed. Short-term seizure control rates were compared between groups with or without coexisting seizures.

RESULTS

We identified 27 coexisting seizures in 24 of the 109 patients (22%). The most common type of seizure was generalized tonic seizure followed by myoclonic, focal tonic, tonic-clonic, hypokinetic, and versive seizures. Rates of preterm birth and birth asphyxia were significantly higher in patients with coexisting seizures. Initial anticonvulsant was vigabatrin (103 patients), valproic acid (five patients), and topiramate (one patient). There was no significant difference in short-term seizure freedom (overall seizure-free rates in patients without coexisting seizures vs. those with: 29.2% vs. 11.1% at 2 months, 36.1% vs. 22.2% at 4 months, and 41.7% vs. 27.8% at 6 months). Seizure freedom was significantly lower in the symptomatic groups compared with non-symptomatic groups.

CONCLUSIONS

Long-term video-EEG monitoring is required as an initial evaluation in patients with infantile spasms, especially when there are reports of coexisting seizures, or a history of preterm birth or birth asphyxia. Presence of coexisting seizures was not related to poor seizure control in the short-term treatment period.

Neuro-lmages of Patients with Infantile Spasm

With the intention of assessing the neuro-imaging, clarifying the percentages of symptomatic, idiopathic and cryptogenic cases and identifying the underlying causes, records were reviewed retrospectively of 30 children with infantile spasm admitted to Hamad Medical Corporation, Doha, Qatar. Twenty-three patients were symptomatic, four idiopathic and three cryptogenic. Brain CT and MRI scans of 13 cases detected similar neuro-imaging findings in nine cases while MRI provided more information in another four cases. Three patients had normal neuro-images despite persistently abnormal EEGs. We conclude that MRI scans are superior to CT scans in detecting areas of cortical dysgenesis, disorders of neuronal migration, or disorders of myelination although more advanced studies are required for patients with persistently abnormal EEGs but normal MRIs.

Predicting antiepileptic drug response in children with epilepsy

In clinical practice, after diagnosis and when treatment has begun, it is important to predict as soon as possible which children will become seizure-free and which are likely to develop medically intractable seizures. This article summarizes factors predicting seizure remission in childhood-onset epilepsy treated with antiepileptic drugs (AEDs). Sustained seizure remission can be expected in over 90% of idiopathic epilepsies of childhood and in neurologically normal children with epilepsy having infrequent seizures showing early remission after starting treatment with AEDs. Even in the presence of symptomatic etiology of epilepsy--focal seizures and syndromes; high seizure frequency prior to or during treatment; seizure clustering; and poor or delayed response to first adequate drug therapy--up to 60% of children with treated epilepsy are able to enter long-term remission. However, remission can be expected in only 30% or less of those with catastrophic epilepsies of childhood.

Safety and efficacy of vigabatrin for the treatment of infantile spasms

In 2009, vigabatrin became the first FDA approved medication for the treatment of infantile spasms in the United States. There are few well-designed prospective studies comparing the drug to placebo or other modalities used in the treatment of infantile spasms. The available data have demonstrated that vigabatrin is efficacious in the treatment of infantile spasms regardless of underlying etiology, but that it is particularly beneficial in patients with a diagnosis of tuberous sclerosis. Adrenocorticotropic hormone (ACTH), the only other medication with robust efficacy data, has been used as first line therapy for infantile spasms associated with other etiologies, and in general controls spasms sooner than vigabatrin, though relapse is common with both therapies. Vigabatrin is generally well tolerated. However, use has been associated with permanent loss of peripheral vision in some patients. In children with tuberous sclerosis, vigabatrin should be considered as initial therapy for infantile spasms. It is a viable alternative for patients with suboptimal response, contraindications or intolerance to ACTH.

Persistence of hypsarrhythmia in children beyond the age of three years

Occurrence of hypsarrhythmia after the age of 3 years is rare. The objective of this study is to describe a group of patients who have persistence of hypsarrhythmia after the age of 3 years. The authors retrospectively reviewed the EEGs of 24 patients with hypsarrhythmia. Electroencephalographies (EEGs) were scored using a hypsarrhythmia scale. The clinical data of 7 patients with EEG scores greater than 9 at ages ≥ 3 years were analyzed. The mean age was 5.7 years (range, 3-8.7 years). EEG background amplitudes ranged from 200 to 500 µV in 5 patients and it was greater than 500 µV in the other 2. Six patients had electrodecremental responses. The etiology was developmental in 3 patients, mitochondrial disease in 2, and hypoxic ischemic encephalopathy in 2. Our study suggests that a subgroup of patients with hypsarrhythmia may not transition to a Lennox-Gastaut pattern or normalization after the age of 3 years.

Infantile spasms: does season influence onset and long-term outcome?

To study whether onset of infantile spasms manifests seasonal variation, as previously reported, and whether any such seasonality is associated with treatment response and long-term outcome, data for 57 patients were retrospectively reviewed. The data were collected from hospital files and through a mail survey of children with infantile spasms born from 1980 to 2002 and monitored at the University Children's Hospital of Berne, Switzerland. The mean age at time of onset of infantile spasms was 7 months (range, 0.75-40), at diagnosis 8 months (range, 1-42) and at follow-up 11.3 years (range, 1-23 years). In 77% of participants, the etiology of infantile spasms was known (symptomatic); in the remaining 23% it was not known (nonsymptomatic). In contrast to previous findings, onset of infantile spasms was not associated with calendar month, photoperiod, or global solar radiation. Long-term prognosis was poor: 4 of the 57 (7%) children died; 49 (86%) had cognitive impairment and 40 (70%) had physical impairment; 31 (54%) had cerebral palsy, 37 had (65%) persistent seizures, and 9 (16%) had Lennox-Gastaut syndrome. Symptomatic infantile spasms were associated with worse cognitive outcome (P < 0.001), but treatment modality and overall duration of infantile spasms were not. There was no association of calendar month or photoperiod at onset with cognitive outcome or treatment response.

Infantile spasms: little seizures, BIG consequences

Infantile spasms is one of the "catastrophic childhood epilepsies" because of the difficulty in controlling seizures and the association with mental retardation. However, early recognition, a careful diagnostic evaluation, and proper treatment may allow some children to attain seizure control and to achieve a normal, or at least much improved, level of development. Thus, there is the opportunity to have an important impact in the lives of these unfortunate children and their families.

Increased risk of death among children with Lennox-Gastaut syndrome and infantile spasms

The magnitude and causes of death among a cohort of children with epilepsy were determined. A follow-up study with a population-based cohort of 10-year-old children in the metropolitan Atlanta area with epilepsy was conducted. The National Death Index and linkage to State of Georgia death certificates were used to identify deaths. The authors estimated the expected numbers of deaths by applying mortality rates adjusted by age, race, and sex for the entire state of Georgia to the population for the follow-up period. Among the 688 children who were in the final epilepsy cohort, 64 deaths occurred; 20.6 deaths were expected (mortality ratio adjusted for age, race, and sex = 3.11). The mortality ratios for children with Lennox-Gastaut syndrome and infantile spasms were 13.92 and 11.91, respectively. Children and adolescents with epilepsy, especially those with Lennox-Gastaut syndrome or infantile spasms, have an increased risk of death.