Multicenter long-term follow-up of children with idiopathic West syndrome: ACTH versus vigabatrin

Fifteen years of real-world data on the use of vigabatrin in individuals with infantile epileptic spasms syndrome

OBJECTIVE

This study was undertaken to evaluate our treatment algorithm for infantile epileptic spasms syndrome (IESS) used between 2000 and 2018. We initiated vigabatrin (VGB), and steroids were added if the electroclinical response (spasms and electroencephalogram [EEG]) to VGB was not obtained or incomplete.

METHODS

Individuals with IESS treated with VGB were recruited from our hospital clinical data warehouse based on electronic health records (EHRs) generated since 2009 and containing relevant keywords. We confirmed the diagnosis of IESS. Clinical, EEG, imaging, and biological data were extracted from the EHRs. We analyzed factors associated with short-term response, time to response, relapse, time to relapse of spasms, and the presence of spasms at last follow-up.

RESULTS

We collected data from 198 individuals (female: 46.5%, IESS onset: 6 [4.5-10.3] months, follow-up: 4.6 [2.5-7.6] years, median [Q1-Q3]) including 129 (65.2%) with identifiable etiology. VGB was started 17 (5-57.5) days after IESS diagnosis. A total of 113 individuals were responders (57.1% of the cohort), 64 with VGB alone and 38 with VGB further combined with steroids (56.6% and 33.6% of responders, respectively). Among responders, 33 (29%) experienced relapses of spasms, mostly those with later onset of spasms (p = .002) and those who received VGB for <24 months after spasms cessation compared to a longer duration on VGB (45% vs. 12.8%, p = .003). At follow-up, 92 individuals were seizure-free (46.5% of the whole cohort), including 26 free of therapy (13.1%). One hundred twelve individuals (56.6%) were still receiving VGB, with a duration of 3.2 (1.75-5.7) years.

SIGNIFICANCE

Our sequential protocol introducing VGB then adding steroids is an effective alternative to a combined VGB-steroids approach in IESS. It avoids steroid-related adverse events, as well as those from VGB-steroid combination. According to our data, a period of 7 days seems sufficient to assess VGB response and enables the addition of steroids rapidly if needed. Continuing VGB for 2 years may balance the risk of relapse and treatment-induced adverse events.

Differential regulation of gene expression pathways with dexamethasone and ACTH after early life seizures

Early-life seizures (ELS) are associated with persistent cognitive deficits such as ADHD and memory impairment. These co-morbidities have a dramatic negative impact on the quality of life of patients. Therapies that improve cognitive outcomes have enormous potential to improve patients' quality of life. Our previous work in a rat flurothyl-induction model showed that administration of adrenocorticotropic hormone (ACTH) at time of seizure induction led to improved learning and memory in the animals despite no effect on seizure latency or duration. Administration of dexamethasone (Dex), a corticosteroid, did not have the same positive effect on learning and memory and has even been shown to exacerbate injury in a rat model of temporal lobe epilepsy. We hypothesized that ACTH exerted positive effects on cognitive outcomes through beneficial changes to gene expression and proposed that administration of ACTH at seizure induction would return gene-expression in the brain towards the normal pattern of expression in the Control animals whereas Dex would not. Twenty-six Sprague-Dawley rats were randomized into vehicle- Control, and ACTH-, Dex-, and vehicle- ELS. Rat pups were subjected to 60 flurothyl seizures from P5 to P14. After seizure induction, brains were removed and the hippocampus and PFC were dissected, RNA was extracted and sequenced, and differential expression analysis was performed using generalized estimating equations. Differential expression analysis showed that ACTH pushes gene expression in the brain back to a more normal state of expression through enrichment of pathways involved in supporting homeostatic balance and down-regulating pathways that might contribute to excitotoxic cell-damage post-ELS.

Assessing Risk for Relapse among Children with Infantile Spasms Using the Based Score after ACTH Treatment: A Retrospective Study

Introduction

Even though adrenocorticotropic hormone (ACTH) demonstrated powerful efficacy in the initially successful treatment of infantile spasms (IS), nearly one-half of patients whose spasms were once suppressed experienced relapse. There is currently no validated method for the prediction of the risk of relapse. The Burden of Amplitudes and Epileptiform Discharges (BASED) score is an electroencephalogram (EEG) grading scale for children with infantile spasms. We sought to determine whether an association exists between the BASED score after ACTH treatment and relapse after initial response with ACTH.

Methods

Children with IS who achieved initial response after ACTH treatment were selected as the study subjects. Those who experienced relapse within 12 months after ACTH treatment were categorized as the relapse group, and those who did not were categorized as the non-relapse group. Their general clinical data and EEG data (using BASED scoring) after ACTH treatment were collected, and compared between groups. Cox proportional hazards models were fit to determine factors associated with relapse.

Results

A total of 64 children with IS were enrolled in the study, of which 37 (57.8%) experienced a relapse, and the median duration after ACTH treatment was 3 (1.5, 6) months. The BASED score was significantly higher in the relapse group than in the non-relapse group. Cox modeling demonstrated that BASED score was independently associated with relapse. The patients with a score greater than or equal to 3 showed a high rate (89.3%) of relapse. The relapse group had stronger, more stable EEG functional networks than the non-relapse group, and there were obvious correlations between BASED score and functional connectivity.

Conclusion

This study suggests the BASED score after ACTH treatment has potential value as a predictor for relapse after initial response. Children with IS who have a BASED score greater than or equal to 3 after the initial response of ACTH carry a high risk of relapse within 1 year.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-022-00347-7.

Comparison of Efficacy and Safety of Low- Versus High-Dose Oral Prednisolone in Infantile Spasm (IS): An Open Label Randomized Controlled Trial at the Children’s Hospital & Institute of Child Health, Multan, Pakistan

Background: Infantile spasm (IS) is an epileptic syndrome characterized by epileptic spasms, hypsarrhythmia on electroencephalography (EEG), and high risk of neurodevelopmental regression. This study was done to compare the efficacy and safety of the high versus the usual dose in children with IS.

Methodology: This open label randomized controlled trial was conducted at Department of Pediatric Neurology, The Children’s Hospital & Institute of Child Health, Multan, Pakistan, from January 1, 2020 to December 31, 2020. A total of 62 children (31 in each group) aged three months to two years presenting with epileptic spasms (at least one cluster per day) with EEG evidence of hypsarrhythmia were included. All 62 children were randomized to receive either high-dose prednisolone (10mg per dose four times a day) or the usual-dose prednisolone (2mg/kg/day thrice a day) for 14 days. Primary outcome measure was noted in terms of proportion of children who achieved complete, partial, or no response. Secondary outcome measure was proportion of children with adverse effects.

Results: In a total of 62 children, there were 34 (54.8%) male. Overall, mean age was noted to be 9.1±3.4 months. The most common etiology of IS was noted to be hypoxic-ischemic encephalopathy (HIE) in 28 children (45.2%). Significantly better clinical efficacy was reported in high-dose prednisolone group when compared to low-dose prednisolone cases as complete response, partial response and no response were noted in nine (29.0%), eight (25.8%), and 14 (45.2%) patients of low-dose group versus 18 (58.1%), eight (25.8%), and five (16.1%) patients in high-dose group, respectively (p=0.0265). Weight gain was the most frequently reported adverse effects noted in 11 (17.7%) cases. Overall, no statistically significant difference in the frequency of adverse effects (p=0.9573).

Conclusion: In comparison to low-dose prednisolone, high-dose prednisolone was found to be significantly more efficacious among cases of IS. Adverse effect in both treatment groups were relatively low and similar.

Comparison of Cosyntropin, Vigabatrin, and Combination Therapy in New-Onset Infantile Spasms in a Prospective Randomized Trial

Objective: In a randomized trial, we aimed to evaluate the efficacy of cosyntropin injectable suspension, 1 mg/mL, compared to vigabatrin for infantile spasms syndrome. An additional arm was included to assess the efficacy of combination therapy (cosyntropin and vigabatrin) compared with cosyntropin monotherapy. Methods: Children (2 months to 2 years) with new-onset infantile spasms syndrome and hypsarhythmia were randomized into 3 arms: cosyntropin, vigabatrin, and cosyntropin and vigabatrin combined. Daily seizures and adverse events were recorded, and EEG was repeated at day 14 to assess for resolution of hypsarhythmia. The primary outcome measure was the composite of resolution of hypsarhythmia and absence of clinical spasms at day 14. Fisher exact test was used to compare outcomes. Results: 37 children were enrolled and 34 were included in the final efficacy analysis (1 withdrew prior to treatment and 2 did not return seizure diaries). Resolution of both hypsarhythmia and clinical spasms was achieved in in 9 of 12 participants (75%) treated with cosyntropin, 1/9 (11%) vigabatrin, and 5/13 (38%) cosyntropin and vigabatrin combined. The primary comparison of cosyntropin versus vigabatrin was significant (64% [95% confidence interval 21, 82], P < .01). Adverse events were reported in all 3 treatment arms: 31 (86%) had an adverse event, 7 (19%) had a serious adverse event, and 15 (42%) had an adverse event of special interest with no difference between treatment arms. Significance: This randomized trial was underpowered because of incomplete enrollment, yet it demonstrated that cosyntropin was more effective for short-term outcomes than vigabatrin as initial treatment for infantile spasms.

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.

What is the optimal duration for vigabatrin monotherapy in patients with infantile spasms: 6 months or longer?

Vigabatrin (VGB) is approved as monotherapy for pediatric patients with Infantile Spasms (IS). Duration of VGB use should be limited because of the risk of retinal and neurotoxicity, but the optimal length of treatment is unknown. Our study aimed to determine the risk of spasms relapse after 6 months of VGB as first-line therapy in IS patients deemed VGB good responders. The participants were 44 infants with IS who demonstrated both absence of clinical spasms and hypsarrhythmia four weeks after starting VGB, obtained from two cohorts: 29 patients from a multicenter prospective cohort and 15 patients from a retrospective single-center cohort. We divided them post hoc into two groups according to the duration of VGB treatment: 6-month group (n=34) and >6-month group (n=10) and compared outcome between the two groups. No patient in either group had a relapse of spasms. For patients with non-identified etiology (NIE) in the 6 months treatment group, no other seizure types were observed. Late epilepsy, in the form of focal seizures, emerged in only 5/37 patients (3/30 in the 6-month treatment group; 2/7 in the extended treatment group); all within the first 6-9 months after VGB initiation. Our study provides substantial evidence that a shortened VGB course of 6 months could be sufficient to treat and prevent relapse of spasms in children with IS, particularly those with NIE.

Antiepileptogenic effects of rapamycin in a model of infantile spasms due to structural lesions

OBJECTIVE

Infantile spasms may evolve into persistent epilepsies including Lennox-Gastaut syndrome. We compared adult epilepsy outcomes in models of infantile spasms due to structural etiology (multiple-hit model) or focal cortical inflammation and determined the anti-epileptogenic effects of pulse-rapamycin, previously shown to stop spasms in multiple-hit rats.

METHODS

Spasms were induced in 3-day-old male rats via right intracerebral doxorubicin/lipopolysaccharide (multiple-hit model) infusions. Controls and sham rats were used. Separate multiple-hit rats received pulse-rapamycin or vehicle intraperitoneally between postnatal days 4 and 6. In adult mice, video-EEG (electroencephalography) scoring for seizures and sleep and histology were done blinded to treatment.

RESULTS

Motor-type seizures developed in 66.7% of multiple-hit rats, usually from sleep, but were reduced in the pulse-rapamycin-treated group (20%, p = .043 vs multiple-hit) and rare in other groups (0-9.1%, p < .05 vs multiple-hit). Spike-and-wave bursts had a slower frequency in multiple-hit rats (5.4-5.8Hz) than in the other groups (7.6-8.3Hz) (p < .05); pulse rapamycin had no effect on the hourly spike-and-wave burst rates in adulthood. Rapamycin, however, reduced the time spent in slow-wave-sleep (17.2%), which was increased in multiple-hit rats (71.6%, p = .003). Sham rats spent more time in wakefulness (43.7%) compared to controls (30.6%, p = .043). Multiple-hit rats, with or without rapamycin treatment, had right more than left corticohippocampal, basal ganglia lesions. There was no macroscopic pathology in the other groups.

SIGNIFICANCE

Structural corticohippocampal/basal ganglia lesions increase the risk for post-infantile spasms epilepsy, Lennox-Gastaut syndrome features, and sleep dysregulation. Pulse rapamycin treatment for infantile spasms has anti-epileptogenic effects, despite the structural lesions, and decreases the time spent in slow wave sleep.

Infantile Spasms: Outcome in Clinical Studies

Children with infantile spasms are likely to have a poor outcome. Outcome measures for infantile spasms include primary response to treatment, relapse of spasms, neurological development, death, and progression to another type of epilepsy (Consensus Statements of the WEST Delphi Group 2004). This review is based mainly on prospective studies and emphasizes data about the current first-line drugs, adrenocorticotropic hormone, vigabatrin, and prednisolone, taking into account the proportion of patients with known and unknown etiology, which has a very strong effect on seizure outcome. In most studies, hormonal treatment (adrenocorticotropic hormone or prednisolone) is the optimal monotherapy, except for patients with tuberous sclerosis complex, in whom vigabatrin appears superior. Combination therapy (hormones plus vigabatrin) may well be more effective than either agent alone. The underlying etiology is the most important prognostic factor. In studies with a long follow-up (up to 50 years), a favorable cognitive outcome has been observed in approximately one quarter of patients and complete seizure freedom in one-third. Autism is relatively frequent, and premature mortality is high throughout life. Modifiable prognostic factors include early recognition of the spasms with prompt treatment, short duration of hypsarrhythmia, prompt treatment of relapses of spasms and multifocal epileptic discharges, and early treatment of adverse effects. It is hoped that eventually advanced genetics and molecular data will allow an understanding of the pathogenetic mechanisms of many specific etiologies to allow disease-specific treatment such as is emerging for tuberous sclerosis.

Status Epilepticus Manifested as Continuous Epileptic Spasms

Objective: The etiology and outcome of status epilepticus with continuous epileptic spasms have not been fully understood; and only rare cases have been reported in the literature. Here, we described 11 children, who manifested continuous epileptic spasms with various etiologies and different outcomes. Methods: This is a case series study designed to systematically review the charts, video-electroencephalography (video-EEG), magnetic resonance images, and longitudinal follow-up of patients who presented continuous epileptic spasms lasting more than 30 min. Results: Median age at onset was 2 years old, ranging from 2 months to 5.6 years. The etiology of continuous epileptic spasms for these 11 cases consisted of not only some known electro-clinical epilepsy syndromes like West Syndrome and Ohtahara Syndrome, but also secondary symptomatic continuous epileptic spasms, caused by acute encephalitis or encephalopathy, which extends the etiological spectrum of continuous epileptic spasms. The most characteristic feature of these 11 cases was prolonged epileptic spasms, lasting for a median of 13.00 days (95% CI: 7.26-128.22 days). The interictal EEG findings typically manifested as hypsarrhythmia or its variants, including burst suppression. Hospital stays were much longer in acute symptomatic cases than in primary epileptic syndromic cases (59.67 ± 50.82 vs. 15.00 ± 1.41 days). However, the long-term outcomes were extremely poor in the patients with defined electro-clinical epilepsy syndromes, including severe motor and intellectual developmental deficits (follow-up of 4.94 ± 1.56 years), despite early diagnosis and treatment. Continuous epileptic spasms were refractory to corticosteroids, immuno-modulation or immunosuppressive therapies, and ketogenic diet. Conclusion: Continuous epileptic spasms were associated with severe brain impairments in patients with electro-clinical syndromes; and required long hospital stays in patients with acute symptomatic causes. We suggest to include continuous epileptic spasms in the international classification of status epilepticus, as a special form. Further investigations are required to better recognize this condition, better understand the etiology, as well as to explore more effective treatments to improve outcomes.

Clobazam as an adjunctive treatment for infantile spasms

Infantile spasms constitute a catastrophic epileptic condition. Seizures in approximately half of children with infantile spasms fail to improve with initial treatment attempts; at present, data regarding alternative treatments are limited. We assessed the efficacy of clobazam as an adjunctive therapy in patients whose seizures failed to respond to initial regimens of standard treatment for infantile spasms. All patients from Severance Children's Hospital who received clobazam as adjunctive therapy for infantile spasms were selected for the study. The efficacy of clobazam was evaluated by assessing the daily spasm frequency. Patients were categorized as complete responders if the spasms disappeared within 2 weeks of introducing clobazam, and the patients became spasm-free during weeks 3 and 4. Tolerability was gauged by analyzing adverse events and discontinuation rates. In all, 171 patients qualified for the analysis. Clobazam was introduced after the administration of 2.6 (median; interquartile range [IQR], 1.0-4.0) failed antiepileptic drugs (AEDs), at the age of 8.2 months (IQR, 6.0-10.0 months). After clobazam therapy was initiated, 38 (22.2%) patients became spasm-free for ≥2 weeks. Thirteen out of the 38 complete responders remained spasm-free until the last follow-up and did not require the administration of other AEDs. In 10 patients, the electroencephalogram (EEG) tracings were also within normal limits. These patients were successfully weaned off of all AEDs. Patients with conditions of unknown etiology, who had fewer prior exposures to AEDs, and had not received prior adrenocorticotropic hormone (ACTH)/steroids were more likely to have complete spasm control than the others. Adverse effects were minor, and only 6 of 101 (6%) patients who experienced adverse events had their treatments discontinued during the 3-month follow-up period. The most common adverse events observed were hypersalivation, sedation, and sleep disturbance. Thus, clobazam might be an effective and safe alternative therapeutic option in patients whose seizures failed to respond to initial regimens of standard treatment for infantile spasms. Further prospective studies on clobazam for infantile spasms, focusing on specific good response groups, dosing protocols, and long-term outcome are needed.

Infantile Spasms in Children With Down Syndrome: Identification and Treatment Response

Objectives. To evaluate infantile spasms in children with Down syndrome including assessment of efficacy of treatments, presence of treatment lag, and to identify risk factors that may predict the occurrence of infantile spasms in this population. Methods. Medical charts, electroencephalograms, and brain magnetic resonance images were evaluated in 37 children treated for infantile spasms at a single institution from 2005 to 2015. Results. Mean age at diagnosis was 9.16 months, with an average 1.38-month lag from spasms onset to start of medication. Prevalence of heart defects and pulmonary hypertension were significantly higher in those with infantile spams compared with those without. Eighty-one percent receiving adrenocorticotropic hormone as initial treatment experienced remission within 2 weeks, 94.1% had remission at 3 months compared with 18.8% at 2 weeks and 35.3% at 3 months for other first-line treatments. Type of treatment was the only predictor of good outcome. Conclusions. Results stress the importance of early recognition and adrenocorticotropic hormone treatment for this seizure disorder in children with Down syndrome.

Infantile Spasms: Clinical profile and treatment outcomes

Background and Objective

Infantile spasm (IS) is one of the severe epileptic encephalopathies which affect children in early two years of life. Our objective was to determine the clinical profile, etiology and outcome of treatment in children with infantile spasms attending tertiary care hospital at Karachi, Pakistan.

Methods

This is retrospective study of 36 patients out of 94 registered as IS, aged three months to two years, managed and followed up at Aga Khan University Hospital, Karachi, from 2010 to 2015. Data of all children with IS was collected from case record. Details including clinical observations, lab investigations, anti-epileptic medications and treatment outcome was collected and analyzed. Patients who received treatment for six weeks to document response were included. The treatment response was categorized as complete response, partial response (>50% improvement) and no response. Data was analyzed on SPSS using descriptive statistics.

Results

Thirty- six patients (38.29%) with IS fulfilled eligibility criteria. The mean ± SD age at presentation was 4.6±2.1 months. Male to female ratio was 2:1. Consanguinity and developmental motor delay was observed in 66.6% and 89% respectively. Symptomatic etiology was predominant (61%) and hypoxic ischemic insult (32%) was the commonest underlying cause. EEG and MRI were diagnostic tools whereas metabolic studies were not helpful. Multiple antiepileptic drugs were used for seizure control and vigabatrin was the most frequently used (88%) drug. Short term treatment response was not different in idiopathic or symptomatic infantile spasms.

Conclusion

Majority of patients had symptomatic infantile spasms and generalized tonic clonic along with myoclonic jerks were predominant seizure types. EEG and MRI were diagnostic in most of cases. Multiple AEDs were required to control seizures and VGB was most common drug (88%) used. Treatment outcome was not different in idiopathic and symptomatic groups.

Infantile Spasms of Unknown Cause: Predictors of Outcome and Genotype-Phenotype Correlation

BACKGROUND

No large-scale studies have specifically evaluated the outcomes of infantile spasms (IS) of unknown cause, previously known as cryptogenic or idiopathic. The Epilepsy Phenome/Genome Project aimed to characterize IS of unknown cause by phenotype and genotype analysis.

METHODS

We undertook a retrospective multicenter observational cohort of 133 individuals within the Epilepsy Phenome/Genome Project database met criteria for IS of unknown cause with at least six months of follow-up data. Clinical medical records, imaging, and electroencephalography were examined.

RESULTS

Normal development occurred in only 15% of IS of unknown cause. The majority (85%) had clinically documented developmental delay (15% mild, 20% moderate, and 50% severe) at last assessment (median 2.7 years; interquartile interval 1.71-6.25 years). Predictors of positive developmental outcomes included no delay prior to IS (P < 0.001), older age of IS onset (median six months old), and resolution of IS after initial treatment (P < 0.001). Additional seizures after IS occurred in 67%, with predictors being seizures prior to IS (P = 0.018), earlier age of IS onset (median five months old), and refractory IS (P = 0.008). On a research basis, whole exome sequencing identified 15% with de novo variants in known epilepsy genes. Individuals with a genetic finding were more likely to have poor developmental outcomes (P = 0.035).

CONCLUSIONS

The current study highlights the predominately unfavorable developmental outcomes and that subsequent seizures are common in children with IS of unknown cause. Ongoing genetic evaluation of IS of seemingly unknown cause is likely to yield a diagnosis and provide valuable prognostic information.

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.

Effect of vigabatrin on seizure control and safety profile in different subgroups of children with epilepsy

OBJECTIVE

To evaluate the efficacy and safety of vigabatrin in pediatric epilepsy.

METHODS

We retrospectively reviewed patients with epilepsy treated with vigabatrin over a 2-year period at a pediatric tertiary center. We assessed the relationship between seizure frequency, etiology, vigabatrin dose, adverse events, medication discontinuation reasons, and electroencephalography (EEG) characteristics.

RESULTS

One hundred three patients followed at Boston Children's Hospital were treated with vigabatrin and had complete medical records. Within the follow-up interval, 69 (67%) of 103 patients had discontinued vigabatrin therapy. Two patients (1.9%) died during therapy for unknown reasons. Median age at vigabatrin initiation was 8 months (interquartile range [IQR] 5-15). Median starting dose was 48.1 mg/kg per day (IQR 29.8-52.3) with a median target of 100 mg/kg (IQR 81.9-107.9). Median treatment duration was 12.1 months (n = 89, IQR 5.0-22.9) overall, and 13.3 months (IQR 5.2-23.2) for patients who discontinued vigabatrin. The most common reasons for discontinuation were controlled seizures in 31 (43.7%) of 71 and unsatisfactory therapeutic effect in 23 (32.4%) of 71. Median percent seizure reduction from baseline to first follow-up was 83.3% (IQR 27.4-99.8) and 96.7% (IQR 43.3-100) to last follow-up. Twenty-four (38.7%) of 62 patients with a follow-up posttreatment remained seizure-free. Four patients who had initially achieved seizure freedom relapsed. Patients with structural/metabolic etiology had greater median percent seizure reduction at first follow-up than patients with genetic etiology (98.7% vs. 61.4%, respectively, p = 0.001). Hypsarrhythmia resolved after therapy in 18 of 20 (90%, 95% confidence interval [CI] 70-97) patients with pretreatment hypsarrhythmia, and 2 patients presented with hypsarrhythmia posttreatment. Risk of having hypsarrhythmia was reduced by 32% (95% CI 14.9-49.1) posttreatment.

SIGNIFICANCE

Vigabatrin is efficacious in all seizure types and resolved hypsarrhythmia in most patients. In this series with a median treatment duration of 12.1 months, vigabatrin had a good safety profile with a low rate of discontinuation due to nonophthalmologic and ophthalmologic adverse effects.

Preclinical Screening for Treatments for Infantile Spasms in the Multiple Hit Rat Model of Infantile Spasms: An Update

Infantile spasms are the typical seizures of West syndrome, an infantile epileptic encephalopathy with poor outcomes. There is an increasing need to identify more effective and better tolerated treatments for infantile spasms. We have optimized the rat model of infantile spasms due to structural etiology, the multiple-hit rat model, for therapy discovery. Here, we test three compounds administered after spasms induction in the multiple hit model for efficacy and tolerability. Specifically, postnatal day 3 (PN3) male Sprague-Dawley rats were induced by right intracerebral injections of doxorubicin and lipopolysaccharide. On PN5 p-chlorophenylalanine was given intraperitoneally (i.p.). Daily monitoring of weights and developmental milestones was done and rats were intermittently video monitored. A blinded, randomized, vehicle-controlled study design was followed. The caspase 1 inhibitor VX-765 (50-200 mg/kg i.p.) and the GABA_B receptor inhibitor CGP35348 (12.5-100 mg/kg i.p.) each was administered in different cohorts as single intraperitoneal injections on PN4, using a dose- and time-response design with intermittent monitoring till PN5. 17β-estradiol (40 ng/g/day subcutaneously) was given daily between PN3-10 and intermittent monitoring was done till PN12. None of the treatments demonstrated acute or delayed effects on spasms, yet all were well tolerated. We discuss the implications for therapy discovery and challenges of replication trials.

Efficacy of Treatments for Infantile Spasms: A Systematic Review

OBJECTIVES

West syndrome (also known as infantile spasm because of its main seizure type) is a rare form of epilepsy that begins during early infancy. Recent guidelines and reviews on West syndrome recommend the use of adrenocorticotropic hormone steroids, or vigabatrin, as the first-line treatment. However, West syndrome remains to be one of the most challenging epilepsies to treat. Here, we systematically reviewed the current literature obtained during the previous decade. This article provides an overview of the current treatment of infantile spasms.

METHODS

PubMed and EMBASE were searched to retrieve studies on human published during 2005-2015 and to identify patients with clinical diagnosis of infantile spasms. Drug or diet treatments were used as interventions and comparators.

RESULTS

We included 55 studies, of which 1 study was a meta-analysis, 9 were randomized controlled trials, 21 were prospective studies, and 24 were retrospective studies. Topiramate, levetiracetam, zonisamide, and sodium valproate with benzodiazepine (clonazepam or nitrazepam) were found to be potential drugs for treating West syndrome besides adrenocorticotropic hormone, steroids, and vigabatrin. Ketogenic diet and modified Atkins diet were also found to be effective.

CONCLUSIONS

To date, data regarding the efficacy of treatments of West syndrome still remain limited. Some treatments, including topiramate and ketogenic diet, seem promising besides adrenocorticotropic hormone, steroids, and vigabatrin. Well-designed trials are warranted to validate the findings.

Response to second treatment after initial failed treatment in a multicenter prospective infantile spasms cohort

OBJECTIVE

Infantile spasms (IS) represent a severe epileptic encephalopathy presenting in the first 2 years of life. Recommended first-line therapies (hormonal therapy or vigabatrin) often fail. We evaluated response to second treatment for IS in children in whom the initial therapy failed to produce both clinical remission and electrographic resolution of hypsarhythmia and whether time to treatment was related to outcome.

METHODS

The National Infantile Spasms Consortium established a multicenter, prospective database enrolling infants with new diagnosis of IS. Children were considered nonresponders to first treatment if there was no clinical remission or persistence of hypsarhythmia. Treatment was evaluated as hormonal therapy (adrenocorticotropic hormone [ACTH] or oral corticosteroids), vigabatrin, or "other." Standard treatments (hormonal and vigabatrin) were compared to all other nonstandard treatments. We compared response rates using chi-square tests and multivariable logistic regression models.

RESULTS

One hundred eighteen infants were included from 19 centers. Overall response rate to a second treatment was 37% (n = 44). Children who received standard medications with differing mechanisms for first and second treatment had higher response rates than other sequences (27/49 [55%] vs. 17/69 [25%], p < 0.001). Children receiving first treatment within 4 weeks of IS onset had a higher response rate to second treatment than those initially treated later (36/82 [44%] vs. 8/34 [24%], p = 0.040).

SIGNIFICANCE

Greater than one third of children with IS will respond to a second medication. Choosing a standard medication (ACTH, oral corticosteroids, or vigabatrin) that has a different mechanism of action appears to be more effective. Rapid initial treatment increases the likelihood of response to the second treatment.

Response to treatment in a prospective national infantile spasms cohort

OBJECTIVE

Infantile spasms are seizures associated with a severe epileptic encephalopathy presenting in the first 2 years of life, and optimal treatment continues to be debated. This study evaluates early and sustained response to initial treatments and addresses both clinical remission and electrographic resolution of hypsarrhythmia. Secondarily, it assesses whether response to treatment differs by etiology or developmental status.

METHODS

The National Infantile Spasms Consortium established a multicenter, prospective database enrolling infants with new diagnosis of infantile spasms. Children were considered responders if there was clinical remission and resolution of hypsarrhythmia that was sustained at 3 months after first treatment initiation. Standard treatments of adrenocorticotropic hormone (ACTH), oral corticosteroids, and vigabatrin were considered individually, and all other nonstandard therapies were analyzed collectively. Developmental status and etiology were assessed. We compared response rates by treatment group using chi-square tests and multivariate logistic regression models.

RESULTS

Two hundred thirty infants were enrolled from 22 centers. Overall, 46% of children receiving standard therapy responded, compared to only 9% who responded to nonstandard therapy (p < 0.001). Fifty-five percent of infants receiving ACTH as initial treatment responded, compared to 39% for oral corticosteroids, 36% for vigabatrin, and 9% for other (p < 0.001). Neither etiology nor development significantly modified the response pattern by treatment group.

INTERPRETATION

Response rate varies by treatment choice. Standard therapies should be considered as initial treatment for infantile spasms, including those with impaired development or known structural or genetic/metabolic etiology. ACTH appeared to be more effective than other standard therapies.

Predictive factors for relapse of epileptic spasms after adrenocorticotropic hormone therapy in West syndrome

PURPOSE

To investigate whether serial electroencephalographic (EEG) findings can predict relapse of epileptic spasms after synthetic adrenocorticotropic hormone (ACTH) therapy in patients with West syndrome (WS).

SUBJECTS AND METHODS

Thirty-nine WS patients (8 cryptogenic and 31 symptomatic) were included in this study. These patients received ACTH therapy for the first time and were regularly followed up for more than three years at our hospital. Sixteen patients (41.0%) showed seizure relapse (relapse group) and 23 patients (59.0%) did not show relapse (non-relapse group). We used survival analysis to investigate the influence of etiology and presence of epileptic discharges after the ACTH therapy on seizure outcome.

RESULTS

Immediately after the ACTH therapy, etiology was associated with seizure outcome (p=0.003). In the early stage (1 month after the ACTH therapy), only the presence of epileptic discharges (p=0.001) had a significant association with seizure outcome, regardless of etiology. Because all relapsed patients were in the symptomatic group, we performed the same statistical analysis on symptomatic WS patient data only. We found that the group with no epileptic discharges on EEG showed a significantly higher seizure-free rate than those with epileptic discharges in the early stage (p=0.0091).

CONCLUSION

This study demonstrated that serial EEG findings after ACTH therapy are significantly related to relapse of epileptic spasms.

Neonatal and Infantile Epilepsy: Acquired and Genetic Models

The incidence of seizures and epilepsies is particularly high during the neonatal and infantile periods. We will review selected animal models of early-life epileptic encephalopathies that have addressed the dyscognitive features of frequent interictal spikes, the pathogenesis and treatments of infantile spasms (IS) or Dravet syndrome, disorders with mammalian target of rapamycin (mTOR) dysregulation, and selected early-life epilepsies with genetic defects. Potentially pathogenic mechanisms in these conditions include interneuronopathies in IS or Dravet syndrome and mTOR dysregulation in brain malformations, tuberous sclerosis, and related genetic disorders, or IS of acquired etiology. These models start to generate the first therapeutic drugs, which have been specifically developed in immature animals. However, there are challenges in translating preclinical discoveries into clinically relevant findings. The advances made so far hold promise that the new insights may potentially have curative or disease-modifying potential for many of these devastating conditions.

Does treatment have an impact on incidence and risk factors for autism spectrum disorders in children with infantile spasms?

OBJECTIVE

Infantile spasms (IS) are a severe form of childhood epilepsy associated with autism spectrum disorders (ASD) in up to 35% of cases. The objective of this post hoc analysis of our randomized control trial was to determine whether rapid diagnosis and treatment of IS could limit the incidence of ASD while identifying risk factors related to ASD outcome.

METHODS

Patients with IS were randomized in a standardized diagnostic and treatment protocol. Clinical and electroencephalogram (EEG) evaluations were completed at all eight visits over 5 years, while cognitive evaluations were administered at 0, 6, 24 and 60 months, respectively. Autism was initially screened by means of the Checklist for Autism in Toddlers (CHAT) at 24 months, and formally assessed at the 30-and 60-month follow-ups using the Autism Diagnostic Observation Schedule-Generic (ADOS-G).

RESULTS

Of the 69 patients included in the study, 25 could not be assessed due to severe delay or death. Eleven of the 42 patients screened with CHAT, were found to be at risk of an ASD outcome. ADOS was performed in 44 and 10 were diagnosed with ASD. The CHAT proved to correlate highly with the ADOS (80% ppv). Only patients with symptomatic IS developed ASD (p = 0.003). Earlier diagnosis or successful treatment did not correlate with a reduced rate of ASD. Other risk factors were identified such as having chronic epileptic discharges in the frontotemporal areas after disappearance of hypsarrhythmia (p = 0.005 and p = 0.007) and being of nonwhite origin (p = 0.009).

SIGNIFICANCE

ASD was only observed in children with sympyomatic IS. Other clinical risk factors include chronic frontotemporal epileptic activity and being of non-white origin. Early diagnosis and treatment did not prevent ASD as an outcome of IS. However, patients at risk for ASD could be identified early on and should in the future benefit from early intervention to potentially improve their long-term outcome.

Neurodevelopmental outcome of infantile spasms: A systematic review and meta-analysis

BACKGROUND

The aims of this systematic review and meta-analysis were to assess (i) estimates of good neurodevelopmental outcome in infantile spasms (IS), (ii) if neurodevelopmental outcome has changed since the publication of the first guideline on medical treatment of IS in 2004 and (iii) effect of lead time to treatment (LTTT).

METHODS

The Medline, Embase, Cochrane, PsycINFO, Web of Science and Scopus databases, and reference lists of retrieved articles were searched. Studies inclusion criteria were: (i) >5 patients with IS, (ii) mean/median follow-up of >6 months, (iii) neurodevelopmental outcome, and (iv) randomized and observational studies. The data extracted included proportion of good neurodevelopmental outcome, year of publication, cryptogenic or symptomatic IS and LTTT.

RESULTS

Of the 1436 citations screened, 55 articles were included in final analysis, with a total of 2967 patients. The pooled estimate for good neurodevelopmental outcome was 0.236 (95% CI: 0.193-0.286). There was no difference between the proportions of good neurodevelopmental outcome for the 21 studies published after 2004 [0.264 (95% CI: 0.197-0.344)] compared to the 34 studies published before 2004 [0.220 (95% CI: 0.168-0.283)] (Q value=0.862, p=0.353). The pooled estimate of good neurodevelopmental outcome for cryptogenic IS [0.543 (95% CI: 0.458-0.625)] was higher than symptomatic IS [0.125 (95% CI: 0.09-0.171)] (Q value=69.724, p<0.001). Risk ratio of LTTT <4weeks relative to >4weeks for good neurodevelopmental outcome of 8 studies was 1.519 (95% CI: 1.064-2.169).

CONCLUSION

Neurodevelopmental outcome was overall poor in patients with IS and has not changed since the publication of first guideline on IS. Although cryptogenic IS has better prognosis than symptomatic IS, the outcome for cryptogenic IS remained poor. There was heterogeneity in neurodevelopmental outcome ascertainment methods, highlighting the need for a more standardized and comprehensive assessment of cognitive, behavioural, emotional and functional outcomes.

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.

Recent advances in the pharmacotherapy of infantile spasms

Adrenocorticotrophic hormone (ACTH), oral corticosteroids and vigabatrin are now first-line treatments for infantile spasms in the US and Europe. There is now increased knowledge regarding the role of ACTH, corticosteroids and vigabatrin (e.g. efficacy, doses, side effects, treatment in specific aetiological subtypes of infantile spasms), and other antiepileptic drugs (i.e. topiramate, valproate, zonisamide, sulthiame, levetiracetam, lamotrigine, pyridoxine, ganaxolone), as well as adjunctive flunarizine and novel drugs not yet in clinical use for infantile spasms (i.e. pulse rapamycin and melanocortin receptor agonists). The existence of a latent period, weeks to months following a precipitating brain insult, raises the possibility of preventive interventions. Recent experimental data emerging from animal models of infantile spasms have provided optimism that new and innovative treatments can be developed, and knowledge that drug treatment can affect long-term cognitive outcome is increasing. The aim of this article is to review recent developments in the pharmacotherapy of infantile spasms and to highlight the practical implications of the latest research.

Sweep visually evoked potentials and visual findings in children with West syndrome

BACKGROUND

West syndrome (WS) is a type of early childhood epilepsy characterized by progressive neurological development deterioration that includes vision.

AIM

To demonstrate the clinical importance of grating visual acuity thresholds (GVA) measurement by sweep visually evoked potentials technique (sweep-VEP) as a reliable tool for evaluation of the visual cortex status in WS children.

METHODS

This is a retrospective study of the best-corrected binocular GVA and ophthalmological features of WS children referred for the Laboratory of Clinical Electrophysiology of Vision of UNIFESP from 1998 to 2012 (Committee on Ethics in Research of UNIFESP n° 0349/08). The GVA deficit was calculated by subtracting binocular GVA score (logMAR units) of each patient from the median values of age norms from our own lab and classified as mild (0.1-0.39 logMAR), moderate (0.40-0.80 logMAR) or severe (>0.81 logMAR). Associated ophthalmological features were also described.

RESULTS

Data from 30 WS children (age from 6 to 108 months, median = 14.5 months, mean ± SD = 22.0 ± 22.1 months; 19 male) were analyzed. The majority presented severe GVA deficit (0.15-1.44 logMAR; mean ± SD = 0.82 ± 0.32 logMAR; median = 0.82 logMAR), poor visual behavior, high prevalence of strabismus and great variability in ocular positioning. The GVA deficit did not vary according to gender (P = .8022), WS type (P = .908), birth age (P = .2881), perinatal oxygenation (P = .7692), visual behavior (P = .8789), ocular motility (P = .1821), nystagmus (P = .2868), risk of drug-induced retinopathy (P = .4632) and participation in early visual stimulation therapy (P = .9010).

CONCLUSIONS

The sweep-VEP technique is a reliable tool to classify visual system impairment in WS children, in agreement with the poor visual behavior exhibited by them.

Prenatal corticosteroids modify glutamatergic and GABAergic synapse genomic fabric: insights from a novel animal model of infantile spasms

Prenatal exposure to corticosteroids has long-term postnatal somatic and neurodevelopmental consequences. Animal studies indicate that corticosteroid exposure-associated alterations in the nervous system include hypothalamic function. Infants with infantile spasms, a devastating epileptic syndrome of infancy with characteristic spastic seizures, chaotic irregular waves on interictal electroencephalogram (hypsarhythmia) and mental deterioration, have decreased concentrations of adrenocorticotrophic hormone (ACTH) and cortisol in cerebrospinal fluid, strongly suggesting hypothalamic dysfunction. We have exploited this feature to develop a model of human infantile spasms by using repeated prenatal exposure to betamethasone and a postnatal trigger of developmentally relevant spasms with NMDA. The spasms triggered in prenatally primed rats are more severe compared to prenatally saline-injected ones and respond to ACTH, a treatment of choice for infantile spasms in humans. Using autoradiography and immunohistochemistry, we have identified a link between the spasms in our model and the hypothalamus, especially the arcuate nucleus. Transcriptomic analysis of the arcuate nucleus after prenatal priming with betamethasone but before trigger of spasms indicates that prenatal betamethasone exposure down-regulates genes encoding several important proteins participating in glutamatergic and GABAergic transmission. Interestingly, there were significant sex-specific alterations after prenatal betamethasone in synapse-related gene expression but no such sex differences were found in prenatally saline-injected controls. A pairwise relevance analysis revealed that, although the synapse gene expression in controls was independent of sex, these genes form topologically distinct gene fabrics in males and females and these fabrics are altered by betamethasone in a sex-specific manner. These findings may explain the sex differences with respect to both normal behaviour and the occurrence and severity of infantile spasms. Changes in transcript expression and their coordination may contribute to a molecular substrate of permanent neurodevelopmental changes (including infantile spasms) found after prenatal exposure to corticosteroids.

Adrenocorticotropic hormone for the treatment of West Syndrome in children

OBJECTIVE

To review the current literature on the efficacy and safety of low- versus high-dose adrenocorticotropic hormone (ACTH) regimens, low-dose ACTH regimens, and comparison of ACTH with oral corticosteroids or vigabatrin for the treatment of West syndrome.

DATA SOURCES

A literature search was performed using MEDLINE, PubMed, and Inter national Pharmaceutical Abstracts (1975-November 2012) to identify studies for inclusion. In addition, reference citations from identified publications were reviewed. The following search terms were used: infantile spasms, West syndrome, adrenocorticotropic hormone, corticotropin, symptomatic West syndrome, cryptogenic West syndrome, pediatric, children, infant, adolescent, and neonate.

STUDY SELECTION AND DATA EXTRACTION

Studies included in this article evaluated low-dose versus high-dose ACTH, low-dose ACTH, and ACTH compared with vigabatrin and oral corticosteroids. Data reporting the efficacy and adverse effects of ACTH, vigabatrin, and oral corticosteroids were extracted from each publication. Only English-language publications were included. We initially reviewed 20 studies, and 14 were included: 5 prospective randomized clinical trials and 9 chart reviews.

DATA SYNTHESIS

West syndrome is an age-specific epileptic disorder that occurs in infancy and early childhood. It is characterized by the triad of infantile spasms, neurodevelopmental regression or delay, and hypsarrhythmia on electroencephalogram (EEG). The efficacy and adverse events of ACTH with different dosage regimens were reviewed and analyzed. ACTH compared with vigabatrin and oral corticosteroids was also evaluated. Based on this review, low-dose ACTH is probably as effective as high-dose ACTH. Compared with other agents, ACTH is suggested to be more effective than oral corticosteroids, and compared with vigabatrin, it has improved outcomes in the cessation of spasms. However, studies evaluating the efficacy of ACTH are limited by small sample size, inconsistent dosage regimens, and the use of synthetic or natural ACTH products. Serious adverse events, including intracranial hemorrhage, brain atrophy, Cushing syndrome, infection, weight gain, and hypertension, may deter the use of ACTH. Short-term therapy is recommended to reduce the risk of adverse effects.

CONCLUSIONS

The current literature suggests that short-term, low-dose ACTH should be considered first-line treatment of infantile spasms.

West syndrome: response to valproate

Management of West syndrome is unsatisfactory. In our clinic we observed that a significant proportion of patients respond to usual dose of valproate. Objective: To prospectively assess the efficacy of valproate in controlling infantile spasms in West syndrome. Methods: Consecutive patients presenting with West syndrome to the Pediatric Neurology Clinic or general outpatient department (OPD) were enrolled for study. Those who were not on any treatment were given valproate in a dose of 30 mg/kg/day while awaiting investigations. Patients were followed up every 2 weeks. Predefined criteria for definition of West syndrome and response were used. Those showing partial/poor response or relapse on valproate were given hormonal therapy. Results: One hundred children with West syndrome were enrolled. Ninety one children were started on valproate. Of these 36 (39.5%) showed a good response, but seven later relapsed while on same dose of valproate and three were lost to follow up. Later age at onset and typical hypsarrhythmia on EEG were associated with good sustained response to valproate while a history of delayed cry at birth was associated with partial or poor response. Sixty two patients who responded poorly to or relapsed on valproate were put on hormonal treatment in addition. Of these 36 (58.1%) had a good response but 11 later relapsed after stopping treatment and two were lost to follow up. Conclusion: Valproate may have a role in treatment of West syndrome in a selected group of patients.

Diagnosis delay in West syndrome: misdiagnosis and consequences

West syndrome or infantile spasms is one of the most frequent epileptic syndromes in the first year of life. The clinical symptoms of infantile spasms are very different than any other type of seizure because of both the absence of paroxysmal motor phenomena (i.e., as in a convulsion) and the lack of significant duration of loss of consciousness (i.e., as in absence epilepsy). Infantile spasms may lead to misdiagnosis by pediatricians and other primary care providers. We assessed the missed diagnoses prior to the diagnosis of infantile spasms. We hypothesized that a delay in treatment may have consequences on neurologic outcome. We conducted a multicenter, retrospective, observational study to evaluate occurrence of misdiagnosis and its possible consequences. We performed a multivariate analysis to evaluate the risk for the outcome 2 years after the diagnosis of infantile spasms. We included 83 infants over a 5-year period. The majority of consulted physicians (301 of 362) did not suggest any specific diagnosis while the others suggested gastroesophageal reflux (7 %), constipation (7 %), or colitis (3 %). Results indicated that a poor outcome was related to a delay in diagnosis, which was observed regardless of the existence of cognitive involvement prior to the start of infantile spasms (Relative Risk: RR 12.08 [1.52-96.3]). These results highlight the importance of making an early diagnosis of infantile spasms.

Epileptic encephalopathies in adults and childhood

Epileptic encephalopathies are motor-mental retardations or cognitive disorders secondary to epileptic seizures or epileptiform activities. Encephalopaties due to brain damage, medications, or systemic diseases are generally not in the scope of this definition, but they may rarely accompany the condition. Appropriate differential diagnosis of epileptic seizures as well as subclinical electroencephalographic discharges are crucial for management of seizures and epileptiform discharges and relative regression of cognitive deterioration in long-term followup. Proper antiepileptic drug, hormonal treatment, or i.v. immunoglobulin choice play major role in prognosis. In this paper, we evaluated the current treatment approaches by reviewing clinical electrophysiological characteristics of epileptic encephalopathies.

Infantile spasms: treatment challenges

OPINION STATEMENT

Infantile spasms (IS) represent a major therapeutic challenge, as cessation of spasms and normalization of the electroencephalogram (elimination of hypsarrhythmia) are mandatory to prevent cognitive deterioration in previously healthy infants, or to preserve neurocognitive function among those neurologically affected prior to onset of IS. Traditionally, this epilepsy syndrome has been considered a "catastrophic" epilepsy, not only for its frequent refractoriness, but mostly due to its effect on cognition. Nevertheless, a change of attitude among pediatric epileptologists is probably warranted, as enough evidence and clinical experience demonstrate that early, aggressive therapy, especially with adrenocorticotropic hormone (ACTH), may not only lead to cessation of spasms, but often leads to the cure of infants with idiopathic/cryptogenic IS. Some ACTH protocols such as that prescribed in Israel (tetracosactide ACTH) appear to be highly efficacious in guarantying a good or even excellent prognosis in idiopathic IS. Moreover, oral prednisolone is a promising and much less expensive alternative to IM ACTH. Vigabatrin does have a role as a first-line agent, especially for tuberous sclerosis patients, but evidence supports hormonal therapy as the initial treatment. The role of pyridoxine and the ketogenic diet still needs to be established; given the efficacy of a much shorter tetracosactide ACTH protocol, there may be no need for the long-term diet, despite its efficacy. Finally, a very promising drug has been developed (CP-115) that may altogether replace the current therapeutic regimens in the near future.

Outcomes of epileptic spasms in patients aged less than 3 years: single-center United States experience

Retrospective review was performed of children aged <3 years with epileptic spasms at our center from 2004-2010. Short-term (<6 months) and long-term (≥6 months) outcomes were assessed. We included 173 children (104 boys; median age of onset, 6.8 months) with epileptic spasms of known (62%) and unknown (38%) etiology. Treatments included adrenocorticotropic hormone (n = 103), vigabatrin (n = 82), phenobarbital (n = 34), and other agents (n = 121). Short-term treatment with adrenocorticotropic hormone and vigabatrin provided better epileptic spasm control in groups with known and unknown etiology than other agents. At follow-up (6-27 months), 54% of children manifested seizures, and 83% manifested developmental delay. Known etiology was a predictor of poor developmental outcome (P = 0.006), whereas bilateral/diffuse brain lesions predicted both poor development and seizures (P = 0.001 and 0.005, respectively). Initial presentations of epileptic spasms with hypotonia or developmental delay most strongly predicted both seizures and neurodevelopmental outcomes (P < 0.001). In a child presenting with epileptic spasms with developmental delay or hypotonia, no specific treatment may offer superior benefit.

West syndrome: early remission is not assurance of normal final outcome

BACKGROUND

West syndrome (WS), an age-specific epilepsy of infancy and early childhood, considered of poor prognosis, may have remission. With the objective of describing the clinical features, treatment and outcome of the children with WS followed in a Latin American country, we devised a retrospective study.

METHODS

Infants with recurrent spasms, and typical or atypical hypsarrhythmia on electroencephalography (EEG) were included, and their medical report reviewed with particular interest on therapy (anti-epileptic drug, steroids) and outcome. Short-term (remission of spasms up to 6 months after the beginning) and long-term outcome (development and seizure status over the age of 2 years) were focused.

RESULTS

Of the 37 selected infants, most (29/37, 78.3%) were classified as symptomatic, and neonatal history of hypoxia (10/29) was the most frequent etiology. The majority had a typical hypsarrhythmia EEG pattern. Most used a combination of anti-epileptic drugs and steroids. A favourable short-term outcome occurred in 20 infants, but only three had normal development and were seizure free after the age of 2 years.

CONCLUSION

Early seizure remission is not assurance of normal final outcome in WS.

New drugs for pediatric epilepsy

The last 2 decades have witnessed an unprecedented period of new antiepileptic drug (AED) development. Newer-generation AEDs have been developed with the intention of improving the ease of use, decreasing drug interactions, decreasing adverse side effects, and identifying drugs with unique mechanisms of action, some of which may bear relevance to potential neuroprotective activity. Drug trials have also been refined in some cases to evaluate AED efficacy in children and against distinct epilepsy syndromes. This progress provides many new treatment options for the child neurologist facing children with epilepsy but also introduces the burden of determining appropriate AED choices. Here we highlight 6 new antiepileptic medications recently approved or pending approval for use in the United States: lacosamide, rufinamide, vigabatrin, retigabine, brivaracetam, and clobazam. For each of these medications, we present information regarding the history of drug development, proposed mechanism(s) of action, pharmacokinetics and recommended dosing, evidence for clinical efficacy, tolerability, and when, available, any unique features that are relevant for the pediatric population.

"Epileptic encephalopathy" of infancy and childhood: electro-clinical pictures and recent understandings

There is growing interest in the diagnosis of cognitive impairment among children with epilepsy. It is well known that status of seizures control has to be carefully investigated because it can be sufficient "per se" to cause progressive mental deterioration conditions. Subclinical electroencephalographic discharges may have subtle effects on cognition, learning and sleep patterns, even in the absence of clinical or sub-clinical seizures. In this respect, electroencephalographic monitoring (long-term and nocturnal recording) and in particular an all night video-polysomnography (V-NPSG) record can be crucial to detect the presence of unrecognized seizures and/or an inter-ictal nocturnal EEG discharge increasing. Epileptic encephalopathies (EE) are a group of conditions in which the higher cognitive functions are deteriorate as a consequence of epileptic activity, which, in fact, consists of frequent seizures and/or florid and prolonged interictal paroxysmal discharges, focal or generalized. AEDs represent the first line in opposing the burden of both, the poor seizures control and the poor interictal discharges control, in the cognitive deterioration of EE affected children. Thus, to improve the long-term cognitive/behavioural prognosis in these refractory epileptic children, it should be taken into account both a good seizures control and a strict sleep control, choosing carefully antiepileptic drugs which are able to control not only seizures clinically recognizable but even the EEG discharges onset and its increasing and spreading during sleep. Here, we review the efficacy and safety of the newer AEDs that, to date, are used in the treatment of EE in infancy and childhood.

Treatment of refractory complex partial seizures: role of vigabatrin

Vigabatrin (VGB) is an antiepileptic drug that was designed to inhibit GABA-transaminase, and increase levels of gamma-amino-butyric acid (GABA), a major inhibitory neurotransmitter in the brain. VGB has demonstrated efficacy as an adjunctive antiepileptic drug for refractory complex partial seizures (CPS) and for infantile spasms (IS). This review focuses on its use for complex partial seizures. Although VGB is well tolerated, there have been significant safety concerns about intramyelinic edema and visual field defects. VGB is associated with a risk of developing bilateral concentric visual field defects. Therefore, the use of VGB for complex partial seizures should be limited to those patients with seizures refractory to other treatments. Patients must have baseline and follow-up monitoring of visual fields, early assessment of its efficacy, and ongoing evaluation of the benefits and risks of VGB therapy.