Evaluation of ten prognostic factors affecting the outcome of West syndrome

Etiology-specific subgroup analysis of initial pharmacotherapy in infantile epileptic spasm syndrome: A single-center cohort study

AIM

To evaluate the efficacy of initial pharmacotherapy for infantile epileptic spasm syndrome (IESS) with electro-clinical outcome characteristics.

METHOD

A retrospective comparative cohort study with 280 IESS patients was designed; I. vigabatrin monotherapy (n = 129, 46 %); II. hormonotherapy (ACTH/oral prednisolone) (n = 73, 26 %); and III. vigabatrin plus early initiation of hormonotherapy in the first 14 days (n = 78, 28 %). Two types of outcomes were defined: (1) short-term outcome with spasm cessation time ≤42 days and resolution of hypsarrhythmia on the EEG on ≤3 months and (2) long-term outcome with spasm relapse rate or evolution to a new epileptic syndrome.

RESULTS

The etiology-specific diagnoses of the IESS cohort were defined according to the ILAE classification: structural (n = 131, 46.8 %), genetic (n = 28, 10 %), metabolic (n = 13, 4.6 %), immune-infectious (n = 10, 3.6 %), and unknown (n = 98, 35 %). Each treatment modalities had similar short- and long-term outcome characteristics. However, hormonotherapy with steroids (ACTH/oral prednisolone) provided "early IESS resolution" with spasm cessation and resolution of hypsarrhythmia (p = 0.042). The relapse rates of IESS were significantly higher in the etiology well-defined group compared to the unknown group (p = 0.005). The genetic-etiology specific group was more likely to have evolved to a new electro-clinical syndrome with a rate of 83.3 % than the others (p = 0.039).

CONCLUSION

We observed that the early initiation of hormonotherapy with VGB (sequential therapy) should be investigated in etiology well-defined subgroup with short- and long-term outcome characteristics.

Rapid determination of plasma vigabatrin by LC-ESI-MS/MS supporting therapeutic drug monitoring in children with infantile spasms

Vigabatrin is one of the second-generation anti-seizure medications (ASMs) designated orphan drugs by the FDA for monotherapy for pediatric patients with infantile spasms from 1 month to 2 years of age. Vigabatrin is also indicated as the adjunctive therapy for adults and pediatric patients 10 years of age and older with refractory complex partial seizures. Ideally, the vigabatrin treatment entails achieving complete seizure freedom without significant adverse effects, and the therapeutic drug monitoring (TDM) will make a significant contribution to this aim, which provides a pragmatic approach to such epilepsy care in that the dose tailoring can be undertaken for uncontrollable seizures and in cases of clinical toxicity guided by the drug concentrations. Thus, reliable assays are mandatory for TDM to be valuable, and blood, plasma, or serum are the matrixes of choice. In this study, a simple, rapid, and sensitive LC-ESI-MS/MS method for the measurement of plasma vigabatrin was developed and validated. The sample clean-up was performed by an easy-to-use method, i.e., protein precipitation using acetonitrile (ACN). Chromatographic separation of vigabatrin and vigabatrin-13C,d2 (internal standard) was achieved on the Waters symmetry C18 column (4.6 mm × 50 mm, 3.5 μm) with isocratic elution at a flow rate of 0.35 mL min-1. The target analyte was completely separated by elution with a highly aqueous mobile phase for 5 min, without any endogenous interference. The method showed good linearity over the 0.010-50.0 μg mL-1 concentration range with a correlation coefficient r2 = 0.9982. The intra-batch and inter-batch precision and accuracy, recovery, and stability of the method were all within the acceptable parameters. Moreover, the method was successfully used in pediatric patients treated with vigabatrin and also provided valuable information for clinicians by monitoring plasma vigabatrin levels in our hospital.

The evaluation of the neurocognitive development of the symptomatic West Syndrome patients

Aim: Our study was aimed to determine both demographic and clinical data of patients with symptomatic West Syndrome (WS) and to monitor their neurocognitive development with Bayley Scales of Infant and Toddler Development Screening Test, third edition (Bayley-III) test. Materials and Methods: Fourteen symptomatic WS patients were included in our study. Clinical and demographic data, electroencephalogram (EEG) findings, treatment response, Bayley III developmental test results were recorded before starting the treatment (T0) and in the 12th months of the treatment (T1 and T12). Results: Patients had a significant increase in Bayley-III test scores in all areas at the end of one year (p <0.05). As the patients' EEGs improved, a statistically significant increase was observed in Bayley-III test scores in all areas (p <0.05). However, when the correlation between seizure control and the Bayley-III test scores were evaluated, there was an improvement only in the language area (p< 0,05); but there was no statistically significant difference in other brain areas (p> 0.05). Conclusion: It has been shown that the neurocognitive level gradually improves even in symptomatic type WS with effective treatment during the follow-up of the disease or with the improvement of the EEG findings and seizure control.

West syndrome: A study of 26 patients receiving short-term therapy

OBJECTIVE

We describe the electroclinical characteristics of a series of 26 patients with idiopathic West syndrome (WS), who had an excellent response to treatment with vigabatrin (VGB) and corticosteroids alone or in combination.

METHODS

Evaluating the records of 178 patients with WS studied at Garrahan Hospital, Niño Jesús Hospital, and Clínica San Lucas between January 2005 and June 2017, we selected 26 patients that met the inclusion criteria of idiopathic WS. The inclusion criteria for idiopathic WS were (1) no personal history of disease, (2) normal neurological examination and neurodevelopment, (3) symmetric spasms in clusters not preceded by any other type of seizure, (d) symmetric hypsarrhythmia, (e) normal electroencephalogram (EEG) background, e.g., normal sleep EEG pattern, (f) normal magnetic resonance imaging (MRI) recording, (g) normal neurometabolic and genetic studies, and (h) at least 2 years of follow-up.

RESULTS

Fifteen boys and 11 girls met the inclusion criteria of idiopathic WS. The current age of the children ranges between 2 years 10 months and 12 years 10 months. Age at first epileptic spasms (ES) ranged from 4 to 11 months, with a mean age of 7 and a median of 7.5 months, respectively; ES were in clusters, bilateral and symmetrical in all cases. Spasms were flexor in nine (34.7%), mixed flexor-extensor in 15 (57.7%), and extensor in three (7.6%). In all patients the EEG showed typical pattern of hypsarrhythmia.

CONCLUSION

These patients with idiopathic WS who have an excellent response to initial treatment should be treated for a short period of time with adrenocorticotropic hormone (ACTH) and VGB alone or in combination.

Epilepsy syndromes, etiologies, and the use of next-generation sequencing in epilepsy presenting in the first 2 years of life: A population-based study

OBJECTIVE

Population-based data on epilepsy syndromes and etiologies in early onset epilepsy are scarce. The use of next-generation sequencing (NGS) has hitherto not been reported in this context. The aim of this study is to describe children with epilepsy onset before 2 years of age, and to explore to what degree whole exome and whole genome sequencing (WES/WGS) can help reveal a molecular genetic diagnosis.

METHODS

Children presenting with a first unprovoked epileptic seizure before age 2 years and registered in the Stockholm Incidence Registry of Epilepsy (SIRE) between September 1, 2001 and December 31, 2006, were retrieved and their medical records up to age 7 years reviewed. Children who met the epilepsy criteria were included in the study cohort. WES/WGS was offered in cases of suspected genetic etiology regardless of whether a structural or metabolic diagnosis had been established.

RESULTS

One hundred sixteen children were included, of which 88 had seizure onset during the first year of life and 28 during the second, corresponding to incidences of 139 and 42/100 000 person-years, respectively. An epilepsy syndrome could be diagnosed in 54% of cases, corresponding to a birth prevalence of 1/1100. Structural etiology was revealed in 34% of cases, a genetic cause in 20%, and altogether etiology was known in 65% of children. The highest diagnostic yield was seen in magnetic resonance imaging (MRI) with 65% revealing an etiology. WES/WGS was performed in 26/116 cases (22%), with a diagnostic yield of 58%.

SIGNIFICANCE

Epilepsy syndromes can be diagnosed and etiologies revealed in a majority of early onset cases. NGS can identify a molecular diagnosis in a substantial number of children, and should be included in the work-up, especially in cases of epileptic encephalopathy, cerebral malformation, or metabolic disease without molecular diagnosis. A genetic diagnosis is essential to genetic counselling, prenatal diagnostics, and precision therapy.

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.

Developmental profile at initial presentation in children with infantile spasms

AIM

To describe the baseline developmental profile and influence of clinical and demographic factors on the developmental skills of infants diagnosed with infantile spasms.

METHOD

Ninety-five infants (55 males, 40 females) newly diagnosed with infantile spasms were recruited for a cross-sectional, longitudinal study. All infants underwent Bayley Scales of Infant and Toddler Development assessments in the cognitive, receptive communication, expressive communication, and fine and gross motor developmental domains; they also underwent visual, auditory, and social behaviour assessments. Infants were categorized as 'early' (<6mo) or 'late' (≥6mo) presenters; if presented within 28 days, this was considered as 'early presentation', whereas a delay greater than 28 days was considered as a 'delay in presentation'. Antenatal, perinatal, and postnatal risk factors were identified.

RESULTS

Over 90% of infants showed impairment in all domains, with the majority having severe delay; 99% showed cognitive impairment. Delayed presentation was significantly associated with receptive communication delay (odds ratio [OR]=5.35; 95% confidence interval [CI]=1.05-27.32). Onset at 6 months or less influenced auditory (OR=2.8; 95% CI=1.16-6.8) and visual (OR=3.03; 95% CI=1.22-7.57) behaviours. Neonatal infections impacted both receptive (OR=1.12; 95% CI=1.04-1.2) and expressive communication (OR=1.08; 95% CI=1.02-1.14) delay. Neonatal seizures significantly influenced visual, auditory, and social impairments. Expressive communication and gross motor development shared common perinatal risk factors.

INTERPRETATION

Adverse developmental status at presentation, associated with delayed presentation and neonatal risk factors should alert clinicians to the surveillance of at-risk infants and seek out timely interventions.

WHAT THIS PAPER ADDS

Ninety per cent of infants showed impaired cognitive, communication, and motor skills at presentation. Visual, auditory, and social behaviour impairments were significantly associated with perinatal risks. Visual, auditory, and social behaviour impairments were significantly associated with neonatal seizures.