Hippocampal sclerosis and temporal lobe epilepsy following febrile status epilepticus: The FEBSTAT study.

OBJECTIVE: This study was undertaken to determine whether hippocampal T2 hyperintensity predicts sequelae of febrile status epilepticus, including hippocampal atrophy, sclerosis, and mesial temporal lobe epilepsy. METHODS: Acute magnetic resonance imaging (MRI) was obtained within a mean of 4.4 (SD = 5.5, median = 2.0) days after febrile status on >200 infants with follow-up MRI at approximately 1, 5, and 10 years. Hippocampal size, morphology, and T2 signal intensity were scored visually by neuroradiologists blinded to clinical details. Hippocampal volumetry provided quantitative measurement. Upon the occurrence of two or more unprovoked seizures, subjects were reassessed for epilepsy. Hippocampal volumes were normalized using total brain volumes. RESULTS: Fourteen of 22 subjects with acute hippocampal T2 hyperintensity returned for follow-up MRI, and 10 developed definite hippocampal sclerosis, which persisted through the 10-year follow-up. Hippocampi appearing normal initially remained normal on visual inspection. However, in subjects with normal-appearing hippocampi, volumetrics indicated that male, but not female, hippocampi were smaller than controls, but increasing hippocampal asymmetry was not seen following febrile status. Forty-four subjects developed epilepsy; six developed mesial temporal lobe epilepsy and, of the six, two had definite, two had equivocal, and two had no hippocampal sclerosis. Only one subject developed mesial temporal epilepsy without initial hyperintensity, and that subject had hippocampal malrotation. Ten-year cumulative incidence of all types of epilepsy, including mesial temporal epilepsy, was highest in subjects with initial T2 hyperintensity and lowest in those with normal signal and no other brain abnormalities. SIGNIFICANCE: Hippocampal T2 hyperintensity following febrile status epilepticus predicted hippocampal sclerosis and significant likelihood of mesial temporal lobe epilepsy. Normal hippocampal appearance in the acute postictal MRI was followed by maintained normal appearance, symmetric growth, and lower risk of epilepsy. Volumetric measurement detected mildly decreased hippocampal volume in males with febrile status.

Diagnosis of TBC1D32-associated conditions: Expanding the phenotypic spectrum of a complex ciliopathy.

Exome sequencing is a powerful tool in prenatal and postnatal genetics and can help identify novel candidate genes critical to human development. We describe seven unpublished probands with rare likely pathogenic variants or variants of uncertain significance that segregate with recessive disease in TBC1D32, including four fetal probands in three unrelated pedigrees and three pediatric probands in unrelated pedigrees. We also report clinical comparisons with seven previously published patients. Index probands were identified through an ongoing prenatal exome sequencing study and through an online data sharing platform (Gene Matcher™). A literature review was also completed. TBC1D32 is involved in the development and function of cilia and is expressed in the developing hypothalamus and pituitary gland. We provide additional data to expand the phenotype correlated with TBC1D32 variants, including a severe prenatal phenotype associated with life-limiting congenital anomalies.

Safe use of the ketogenic diet in an infant with microcephaly, epilepsy, and diabetes syndrome: a case report.

BACKGROUND: Microcephaly, epilepsy, and diabetes syndrome (MEDS) is a rare syndromic form of monogenic diabetes caused by bi-allelic loss of function mutations in IER3IP1. In vitro studies have shown that loss of IER31P leads to apoptosis in both neurons and pancreatic ß-cells. Simultaneous management of seizures and diabetes is challenging in patients with MEDS. We present the challenges and successes in the use of ketogenic diet in an infant with insulinopenic diabetes. CASE PRESENTATION: Our term female proband presented at 2 months of age with new onset multifocal seizures followed by the onset of infantile spasms (IS) at 4 months of age. An epilepsy gene panel identified bi-allelic variants, c.239T > G (p.Leu80*) and c.2T > A (initiator codon), in IER3IP1 that were subsequently shown to be inherited in trans. Following initiation of steroid therapy for IS, the patient developed clinically apparent insulin requiring diabetes. Her epilepsy was ultimately refractory to multiple antiseizure medications, thus the ketogenic diet (KD) was initiated. We were able to successfully titrate to a therapeutic KD ratio of 3:1 and maintain a ketotic state without diabetic ketoacidosis (DKA). With intercurrent illnesses, however, the patient had rapid decompensation and mild DKA due to delays in treatment, and for this reason, KD was discontinued after 5 months. CONCLUSIONS: We report two novel IER31P1 mutations in a patient with MEDS and the successful management of the cooccurring conditions of IS and insulinopenic diabetes with the KD. Our experience underscores the importance of careful monitoring during KD as our patient had DKA more easily when on the KD.

Mutations in NCAPG2 Cause a Severe Neurodevelopmental Syndrome that Expands the Phenotypic Spectrum of Condensinopathies.

The use of whole-exome and whole-genome sequencing has been a catalyst for a genotype-first approach to diagnostics. Under this paradigm, we have implemented systematic sequencing of neonates and young children with a suspected genetic disorder. Here, we report on two families with recessive mutations in NCAPG2 and overlapping clinical phenotypes that include severe neurodevelopmental defects, failure to thrive, ocular abnormalities, and defects in urogenital and limb morphogenesis. NCAPG2 encodes a member of the condensin II complex, necessary for the condensation of chromosomes prior to cell division. Consistent with a causal role for NCAPG2, we found abnormal chromosome condensation, augmented anaphase chromatin-bridge formation, and micronuclei in daughter cells of proband skin fibroblasts. To test the functional relevance of the discovered variants, we generated an ncapg2 zebrafish model. Morphants displayed clinically relevant phenotypes, such as renal anomalies, microcephaly, and concomitant increases in apoptosis and altered mitotic progression. These could be rescued by wild-type but not mutant human NCAPG2 mRNA and were recapitulated in CRISPR-Cas9 F0 mutants. Finally, we noted that the individual with a complex urogenital defect also harbored a heterozygous NPHP1 deletion, a common contributor to nephronophthisis. To test whether sensitization at the NPHP1 locus might contribute to a more severe renal phenotype, we co-suppressed nphp1 and ncapg2, which resulted in significantly more dysplastic renal tubules in zebrafish larvae. Together, our data suggest that impaired function of NCAPG2 results in a severe condensinopathy, and they highlight the potential utility of examining candidate pathogenic lesions beyond the primary disease locus.

Delineating the epilepsy phenotype of NGLY1 deficiency.

We delineated the phenotypic spectrum of epilepsy in individuals with NGLY1 deficiency from an international cohort. We collected detailed clinical and electroencephalographic data from 29 individuals with bi-allelic (likely) pathogenic variants in NGLY1 as part of an ongoing prospective natural history study. Participants were evaluated in-person at a single center and/or remotely. Historical medical records were reviewed. Published cases were included for comprehensive phenotyping. Of 29 individuals (mean 11.4 years, range 3-27 years), 17 (58.6%) participants had a history of epilepsy. Seizure onset was in early childhood (mean 43 months, range 2 months to 19 years). The most common seizure types were myoclonic and atonic. Epilepsy course was variable, but 35.2% (6/17) of participants with epilepsy achieved seizure freedom. The most common medications included levetiracetam, valproate, lamotrigine, and clobazam. Electroencephalogram (EEGs) were abnormal in 80% (12/15) of participants with or without epilepsy, although encephalopathy was uncommon. There was a trend in neurodevelopmental outcomes that participants with epilepsy had more developmental delays. In summary, epilepsy is common in NGLY1 deficiency. Over half of the participants had a history of epilepsy and nearly all had EEG abnormalities indicating an increased risk of epilepsy. This work expands the electroclinical phenotype of NGLY1 deficiency and supports a high clinical suspicion for seizures. Some of the more common seizure types (epileptic spasms, myoclonic, and atonic seizures) can be subtle and require counseling to ensure early recognition and treatment to ensure the best possible outcomes. Despite transient liver enzyme abnormalities in this disorder, hepatically metabolized medications were well tolerated.

Randomized trial of lacosamide versus fosphenytoin for nonconvulsive seizures.

OBJECTIVE: The optimal treatment of nonconvulsive seizures in critically ill patients is uncertain. We evaluated the comparative effectiveness of the antiseizure drugs lacosamide (LCM) and fosphenytoin (fPHT) in this population. METHODS: The TRENdS (Treatment of Recurrent Electrographic Nonconvulsive Seizures) study was a noninferiority, prospective, multicenter, randomized treatment trial of patients diagnosed with nonconvulsive seizures (NCSs) by continuous electroencephalography (cEEG). Treatment was randomized to intravenous (IV) LCM 400mg or IV fPHT 20mg phenytoin equivalents/kg. The primary endpoint was absence of electrographic seizures for 24 hours as determined by 1 blinded EEG reviewer. The frequency with which NCS control was achieved in each arm was compared, and the 90% confidence interval (CI) was determined. Noninferiority of LCM to fPHT was to be concluded if the lower bound of the CI for relative risk was >0.8. RESULTS: Seventy-four subjects were enrolled (37 LCM, 37 fPHT) between August 21, 2012 and December 20, 2013. The mean age was 63.6 years; 38 were women. Seizures were controlled in 19 of 30 (63.3%) subjects in the LCM arm and 16 of 32 (50%) subjects in the fPHT arm. LCM was noninferior to fPHT (p = 0.02), with a risk ratio of 1.27 (90% CI = 0.88-1.83). Treatment emergent adverse events (TEAEs) were similar in both arms, occurring in 9 of 35 (25.7%) LCM and 9 of 37 (24.3%) fPHT subjects (p = 1.0). INTERPRETATION: LCM was noninferior to fPHT in controlling NCS, and TEAEs were comparable. LCM can be considered an alternative to fPHT in the treatment of NCSs detected on cEEG. Ann Neurol 2018;83:1174-1185.

Immunotherapy in selected patients with Down syndrome disintegrative disorder.

Down syndrome disintegrative disorder (DSDD) is an increasingly identified condition characterized by cognitive decline, autistic characteristics, insomnia, catatonia, and psychosis in adolescents and young adults with Down syndrome. Previously we reported a higher rate of autoimmune thyroid disease in these patients compared with unaffected individuals with Down syndrome. We therefore hypothesized DSDD may in some cases be immune-mediated. Here we report four cases of DSDD treated with immunotherapy. Families were interviewed retrospectively for symptoms of cognitive decline, autism, catatonia, psychosis, and insomnia before and after treatment, using established scales where possible. Medical records were reviewed for evaluations and treatment. All four patients received intravenous immunoglobulin with or without additional immunotherapy. Significant improvements were seen in catatonia, insomnia, autistic features, cognition, and psychosis. In this small case series of patients with autoimmunity, core symptoms of DSDD improved significantly after immunotherapy. This supports the hypothesis that, in some patients, DSDD is immune-mediated. Immunotherapy should be considered in the treatment of DSDD, particularly in patients with a history of autoimmunity. WHAT THIS PAPER ADDS: Immunotherapy may improve symptoms of catatonia, insomnia, autism severity, cognitive decline, and psychosis in Down syndrome disintegrative disorder.

INMUNOTERAPIA EN PACIENTES SELECCIONADOS CON TRASTORNO DESINTEGRATIVO DEL SÍNDROME DE DOWN: El trastorno desintegrativo del síndrome de Down (TDSD) es una afección cada vez más identificada que se caracteriza por deterioro cognitivo, características autistas, insomnio, catatonia y psicosis en adolescentes y adultos jóvenes con síndrome de Down. Anteriormente informamos una tasa más alta de enfermedad tiroidea autoinmune en estos pacientes en comparación con las personas no afectadas con síndrome de Down. Por lo tanto, hipotetizamos que el TDSD puede, en algunos casos, estar inmunomediado. Aquí presentamos cuatro casos de TDSD tratados con inmunoterapia. Las familias fueron entrevistadas retrospectivamente para los síntomas de deterioro cognitivo, autismo, catatonía, psicosis e insomnio antes y después del tratamiento, utilizando escalas establecidas cuando sea posible. Los registros médicos fueron revisados ​​para evaluaciones y tratamiento. Los cuatro pacientes recibieron inmunoglobulina intravenosa con o sin inmunoterapia adicional. Se observaron mejoras significativas en catatonia, insomnio, características autistas, cognición y psicosis. En esta pequeña serie de casos de pacientes con autoinmunidad, los síntomas centrales de la TDSD mejoraron significativamente después de la inmunoterapia. Esto apoya la hipótesis de que, en algunos pacientes, la TDSD está inmunomediada. La inmunoterapia debe considerarse en el tratamiento de la TDSD, particularmente en pacientes con antecedentes de autoinmunidad.

IMUNOTERAPIA EM PACIENTES SELECIONADOS COM SÍNDROME DE DOWN E TRANSTORNO DESINTEGRATIVO: O transtorno desintegrativo na síndrome de Down (TDSD) é uma condição crescentemente identificada, caracterizada por declínio cognitivo, características autistas, insônia, catatonia, e psicose em adolescente e jovens adultos com síndrome de Down. Nós relatamos previamente uma taxa maior de doença autoimune da tireóide nestes pacientes comparados com indivíduos com síndrome de Down não afetados. Portanto, hipotetizamos que o TDSD pode, em alguns casos, ser imune-mediado. Aqui reportamos quatro casos de TDSD tratados com imunoterapia. As famílias foram entrevistadas retrospectivamente quanto a sintomas de declínio cognitivo, autismo, catatonia, psicose, e insônia antes e depois do tratamento, usando escalas estabelecidas quando possível. Os registros médicos foram revisados quanto a avaliações e tratamento. Todos os quatro pacientes receberam imunoglobulina intravenosa com ou sem imunoterapia adicional. Melhoras significativas foram vistas na catatonia, aspectos autistas, cognição, e psicose. Nesta pequena série de casos de pacientes com auto-imunidade, os sintomas centrais de TDSD melhoraram significativament após imunoterapia. Isso apóia a hipótese de que, em alguns pacientes, o TDSD é imuno-mediado. A imunoterapia deve ser considerada no tratamento do TDSD, particularmente em pacientes com história de autoimunidade.

Prospective clinical trials to investigate clinical and molecular biomarkers.

Among clinical studies, randomized studies as well as well-designed observational studies are providing the highest quality data. In addition, these studies represent a good opportunity to examine biomarkers of ictogenesis and epileptogenesis. To date, no validated molecular or cellular biomarker exists for any aspect of epilepsy. We provide an overview of the inflammatory biomarkers under investigation in prospective clinical studies in epilepsy: proinflammatory cytokines in prolonged febrile seizure; High Mobility Group Box 1 (HMGB1) as a prognosis biomarker in epilepsy and the interaction between inflammation and metabolism, in particular, iron metabolism, in epilepsy. The designs of the European Union EPISTOP project following prospectively patients with tuberous sclerosis from birth to the start of the epilepsy and of the Standard and New Antiepileptic Drugs-II study illustrate how such studies can be used to find new inflammatory biomarkers of ictogenesis and epileptogenesis. If we want to bridge the current gap between having numerous biomarker candidates from preclinical studies and their selective use in clinical practice, we need to explore multiple biologic systems, not just including inflammation. In addition, it is crucial that those involved in the design and support of relevant clinical studies recognize this gap and act accordingly, and in the interests of improving the diagnosis and prognosis for epilepsy.

Plasma cytokines associated with febrile status epilepticus in children: A potential biomarker for acute hippocampal injury.

OBJECTIVE: Our aim was to explore the association between plasma cytokines and febrile status epilepticus (FSE) in children, as well as their potential as biomarkers of acute hippocampal injury. METHODS: Analysis was performed on residual samples of children with FSE (n = 33) as part of the Consequences of Prolonged Febrile Seizures in Childhood study (FEBSTAT) and compared to children with fever (n = 17). Magnetic resonance imaging (MRI) was obtained as part of FEBSTAT within 72 h of FSE. Cytokine levels and ratios of antiinflammatory versus proinflammatory cytokines in children with and without hippocampal T2 hyperintensity were assessed as biomarkers of acute hippocampal injury after FSE. RESULTS: Levels of interleukin (IL)-8 and epidermal growth factor (EGF) were significantly elevated after FSE in comparison to controls. IL-1ß levels trended higher and IL-1RA trended lower following FSE, but did not reach statistical significance. Children with FSE were found to have significantly lower ratios of IL-1RA/IL-1ß and IL-1RA/IL-8. Specific levels of any one individual cytokine were not associated with FSE. However, lower ratios of IL-1RA/IL-1ß, IL-1RA/1L-6, and IL-1RA/ IL-8 were all associated with FSE. IL-6 and IL-8 levels were significantly higher and ratios of IL-1RA/IL-6 and IL-1RA/IL-8 were significantly lower in children with T2 hippocampal hyperintensity on MRI after FSE in comparison to those without hippocampal signal abnormalities. Neither individual cytokine levels nor ratios of IL-1RA/IL-1ß or IL-1RA/IL-8 were predictive of MRI changes. However, a lower ratio of IL-1RA/IL-6 was strongly predictive (odds ratio [OR] 21.5, 95% confidence interval [CI] 1.17-393) of hippocampal T2 hyperintensity after FSE. SIGNIFICANCE: Our data support involvement of the IL-1 cytokine system, IL-6, and IL-8 in FSE in children. The identification of the IL-1RA/IL-6 ratio as a potential biomarker of acute hippocampal injury following FSE is the most significant finding. If replicated in another study, the IL-1RA/IL-6 ratio could represent a serologic biomarker that offers rapid identification of patients at risk for ultimately developing mesial temporal lobe epilepsy (MTLE).

Epilepsy in neurofibromatosis type 1.

OBJECTIVES: To describe the characteristics of epilepsy in patients with Neurofibromatosis type 1 (NF1). METHODS: Analysis of a cohort of consecutive NF1 patients seen in our NF1 clinic during a three-year period. RESULTS: Of the 184 NF1 patients seen during that period, 26 had epilepsy and three had febrile seizures. Of the 26, 17 (65%) had localization-related epilepsy, seven of whom (41%) were drug resistant. Six (23%) had apparently primary generalized epilepsy (0/6 drug resistant), two (8%) Lennox-Gastaut syndrome, and one (4%) West syndrome (all three were drug-resistant). As compared to the patients with no epilepsy, those with epilepsy were more likely to have MRI findings of mesial temporal sclerosis (MTS) (23% vs. 5%, p=0.0064), and cerebral hemisphere tumors (31% vs. 10%, p=0.0079), but not of the other MRI findings including neurofibromatosis bright objects, or optic gliomas. Three of the six patients with MTS underwent temporal lobectomy with subsequent control of their seizures with confirmation of MTS on pathology in 3/3 and presence of coexisting focal cortical dysplasia (FCD) in 2/3. We also have observed three additional patients outside the above study with the association of NF1, MTS, and intractable epilepsy. SIGNIFICANCE: Epilepsy is relatively common in NF1, often occurs in patients with brain tumors or with MTS which can coexist with FCD, can be associated with multiple types of epilepsy syndromes, and when localization-related is often drug-resistant. Patients with NF1 and MTS can respond to medial temporal lobectomy and may have coexisting medial temporal lobe cortical dysplasia.

Risk factors for subsequent febrile seizures in the FEBSTAT study.

OBJECTIVES: To identify risk and risk factors for developing a subsequent febrile seizure (FS) in children with a first febrile status epilepticus (FSE) compared to a first simple febrile seizure (SFS). To identify home use of rescue medications for subsequent FS. METHODS: Cases included a first FS that was FSE drawn from FEBSTAT and Columbia cohorts. Controls were a first SFS. Cases and controls were classified according to established FEBSTAT protocols. Cumulative risk for subsequent FS over a 5-year period was compared in FSE versus SFS, and Cox proportional hazards regression was conducted. Separate analysis examined subsequent FS within FSE. The use of rescue medications at home was assessed for subsequent FS. RESULTS: Risk for a subsequent FSE was significantly increased in FSE versus SFS. Any magnetic resonance imaging (MRI) abnormality increased the risk 3.4-fold (p < 0.05), adjusting for age at first FS and FSE and in analyses restricted to children whose first FS was FSE (any MRI abnormality hazard ratio [HR] 2.9, p < 0.05). The risk for a second FS of any type or of subsequent FS lasting >10 min over the 5-year follow-up did not differ in FSE versus SFS. Rectal diazepam was administered at home to 5 (23.8%) of 21 children with subsequent FS lasting ≥10 min. SIGNIFICANCE: Compared to controls, FSE was associated with an increased risk for subsequent FSE, suggesting the propensity of children with an initial prolonged seizure to experience a prolonged recurrence. Any baseline MRI abnormality increased the recurrence risk when FSE was compared to SFS and when FSE was studied alone. A minority of children with a subsequent FS lasting 10 min or longer were treated with rectal diazepam at home, despite receiving prescriptions after the first FSE. This indicates the need to further improve the education of clinicians and parents in order to prevent subsequent FSE.

Cognitive functioning one month and one year following febrile status epilepticus.

OBJECTIVE: The objective of this study was to determine early developmental and cognitive outcomes of children with febrile status epilepticus (FSE) one month and one year after FSE. METHODS: One hundred ninety four children with FSE were evaluated on measures of cognition, receptive language, and memory as part of the FEBSTAT study and compared with 100 controls with simple febrile seizures (FSs). RESULTS: Children with FSE did not differ dramatically on tasks compared with FS controls at one month after FSE but demonstrated slightly weaker motor development (p=0.035) and receptive language (p=0.034) at one year after FSE. Performances were generally within the low average to average range. Within the FSE cohort, non-White children performed weaker on many of the tasks compared with Caucasian children. At the one-year visit, acute hippocampal T2 findings on MRI were associated with weaker receptive language skills (p=0.0009), and human herpes virus 6 or 7 (HHV6/7) viremia was associated with better memory performances (p=0.047). CONCLUSION: Febrile status epilepticus does not appear to be associated with significant cognitive impairment on early developmental measures, although there is a trend for possible receptive language and motor delay one year after FSE. Further follow-up, which is in progress, is necessary to track long-term cognitive functioning.

Strategies to Maximize Enrollment in a Prospective Study of Comatose Children in the PICU.

OBJECTIVES: To analyze barriers to recruitment encountered during a prospective study in the PICU and evaluate strategies implemented to improve recruitment. DESIGN: Prospective observational study of continuous electroencephalogram monitoring in comatose children. SETTING: PICUs at four North American institutions. PATIENTS: Patients with a Glasgow Coma Scale score of less than or equal to 8 for at least an hour. INTERVENTIONS: Four strategies to increase recruitment were sequentially implemented. MEASUREMENTS AND MAIN RESULTS: The baseline enrollment rate was 2.1 subjects/mo, which increased following the single-site introduction of real-time patient screening using an online dashboard (4.5 subjects/mo), deferred consenting (5.2 subjects/mo), and weekend screening (6.1 subjects/mo). However, the subsequent addition of three new study sites was the greatest accelerator of enrollment (21 subjects/mo), representing a 10-fold increase from baseline (p < 0.0001). CONCLUSIONS: Identifying barriers to recruitment and implementing creative strategies to increase recruitment can successfully increase enrollment rates in the challenging ICU environment.

Exome sequencing followed by large-scale genotyping fails to identify single rare variants of large effect in idiopathic generalized epilepsy.

Idiopathic generalized epilepsy (IGE) is a complex disease with high heritability, but little is known about its genetic architecture. Rare copy-number variants have been found to explain nearly 3% of individuals with IGE; however, it remains unclear whether variants with moderate effect size and frequencies below what are reliably detected with genome-wide association studies contribute significantly to disease risk. In this study, we compare the exome sequences of 118 individuals with IGE and 242 controls of European ancestry by using next-generation sequencing. The exome-sequenced epilepsy cases include study subjects with two forms of IGE, including juvenile myoclonic epilepsy (n = 93) and absence epilepsy (n = 25). However, our discovery strategy did not assume common genetic control between the subtypes of IGE considered. In the sequence data, as expected, no variants were significantly associated with the IGE phenotype or more specific IGE diagnoses. We then selected 3,897 candidate epilepsy-susceptibility variants from the sequence data and genotyped them in a larger set of 878 individuals with IGE and 1,830 controls. Again, no variant achieved statistical significance. However, 1,935 variants were observed exclusively in cases either as heterozygous or homozygous genotypes. It is likely that this set of variants includes real risk factors. The lack of significant association evidence of single variants with disease in this two-stage approach emphasizes the high genetic heterogeneity of epilepsy disorders, suggests that the impact of any individual single-nucleotide variant in this disease is small, and indicates that gene-based approaches might be more successful for future sequencing studies of epilepsy predisposition.

Electrographic seizures after convulsive status epilepticus in children and young adults: a retrospective multicenter study.

OBJECTIVE: To describe the prevalence, characteristics, and predictors of electrographic seizures after convulsive status epilepticus (CSE). STUDY DESIGN: This was a multicenter retrospective study in which we describe clinical and electroencephalographic (EEG) features of children (1 month to 21 years) with CSE who underwent continuous EEG monitoring. RESULTS: Ninety-eight children (53 males) with CSE (median age of 5 years) underwent subsequent continuous EEG monitoring after CSE. Electrographic seizures (with or without clinical correlate) were identified in 32 subjects (33%). Eleven subjects (34.4%) had electrographic-only seizures, 17 subjects (53.1%) had electroclinical seizures, and 4 subjects (12.5%) had an unknown clinical correlate. Of the 32 subjects with electrographic seizures, 15 subjects (46.9%) had electrographic status epilepticus. Factors associated with the occurrence of electrographic seizures after CSE were a previous diagnosis of epilepsy (P = .029) and the presence of interictal epileptiform discharges (P < .0005). The median (p25-p75) duration of stay in the pediatric intensive care unit was longer for children with electrographic seizures than for children without electrographic seizures (9.5 [3-22.5] vs 2 [2-5] days, Wilcoxon test, Z = 3.916, P = .0001). Four children (4.1%) died before leaving the hospital, and we could not identify a relationship between death and the presence or absence of electrographic seizures. CONCLUSIONS: After CSE, one-third of children who underwent EEG monitoring experienced electrographic seizures, and among these, one-third experienced entirely electrographic-only seizures. A previous diagnosis of epilepsy and the presence of interictal epileptiform discharges were risk factors for electrographic seizures.

Emergency management of febrile status epilepticus: results of the FEBSTAT study.

OBJECTIVE: Treatment of seizures varies by region, with no standard emergency treatment protocol. Febrile status epilepticus (FSE) is often a child's first seizure; therefore, families are rarely educated about emergency treatment. METHODS: From 2002 to 2010, 199 subjects, age 1 month to 6 years, were recruited as part of a prospective, multicenter study of consequences of FSE, which was defined as a febrile seizure or series of seizures lasting >30 min. The patients' charts were reviewed. No standardized treatment protocol was implemented for this observational study. RESULTS: One hundred seventy-nine children received at least one antiepileptic drug (AED) to terminate FSE, and more than one AED was required in 140 patients (70%). Median time from the seizure onset to first AED by emergency medical services (EMS) or emergency department (ED) was 30 min. Mean seizure duration was 81 min for subjects given medication prior to ED and 95 min for those who did not (p = 0.1). Median time from the first dose of AED to end of seizure was 38 min. Initial dose of lorazepam or diazepam was suboptimal in 32 (19%) of 166 patients. Ninety-five subjects (48%) received respiratory support by EMS or ED. Median seizure duration for the respiratory support group was 83 min; for the nonrespiratory support group the duration was 58 min (p-value < 0.001). Reducing the time from seizure onset to AED initiation was significantly related to shorter seizure duration. SIGNIFICANCE: FSE rarely stops spontaneously, is fairly resistant to medications, and even with treatment persists for a significant period of time. The total seizure duration is composed of two separate factors, the time from seizure onset to AED initiation and the time from first AED to seizure termination. Earlier onset of treatment results in shorter total seizure duration. A standard prehospital treatment protocol should be used nationwide and education of EMS responders is necessary.

Images: Benign myoclonus of sleep associated with K-complexes on electroencephalography.

In this brief case report on paroxysmal sleep-related movements, we describe an adolescent patient's presentation of brief jerking movements during sleep and the accompanying differential diagnosis. In examining the patient's overnight electroencephalogram we use hallmark sleep architecture to provide reassurance to the patient and her family. CITATION: Silverman A, Miglis MG, Gallentine W. Images: Benign myoclonus of sleep associated with K-complexes on electroencephalography. J Clin Sleep Med. 2024;20(1):183-184.

Identification of a recurrent microdeletion at 17q23.1q23.2 flanked by segmental duplications associated with heart defects and limb abnormalities.

Segmental duplications, which comprise approximately 5%-10% of the human genome, are known to mediate medically relevant deletions, duplications, and inversions through nonallelic homologous recombination (NAHR) and have been suggested to be hot spots in chromosome evolution and human genomic instability. We report seven individuals with microdeletions at 17q23.1q23.2, identified by microarray-based comparative genomic hybridization (aCGH). Six of the seven deletions are approximately 2.2 Mb in size and flanked by large segmental duplications of >98% sequence identity and in the same orientation. One of the deletions is approximately 2.8 Mb in size and is flanked on the distal side by a segmental duplication, whereas the proximal breakpoint falls between segmental duplications. These characteristics suggest that NAHR mediated six out of seven of these rearrangements. These individuals have common features, including mild to moderate developmental delay (particularly speech delay), microcephaly, postnatal growth retardation, heart defects, and hand, foot, and limb abnormalities. Although all individuals had at least mild dysmorphic facial features, there was no characteristic constellation of features that would elicit clinical suspicion of a specific disorder. The identification of common clinical features suggests that microdeletions at 17q23.1q23.2 constitute a novel syndrome. Furthermore, the inclusion in the minimal deletion region of TBX2 and TBX4, transcription factors belonging to a family of genes implicated in a variety of developmental pathways including those of heart and limb, suggests that these genes may play an important role in the phenotype of this emerging syndrome.

Rare deletions at 16p13.11 predispose to a diverse spectrum of sporadic epilepsy syndromes.

Deletions at 16p13.11 are associated with schizophrenia, mental retardation, and most recently idiopathic generalized epilepsy. To evaluate the role of 16p13.11 deletions, as well as other structural variation, in epilepsy disorders, we used genome-wide screens to identify copy number variation in 3812 patients with a diverse spectrum of epilepsy syndromes and in 1299 neurologically-normal controls. Large deletions (> 100 kb) at 16p13.11 were observed in 23 patients, whereas no control had a deletion greater than 16 kb. Patients, even those with identically sized 16p13.11 deletions, presented with highly variable epilepsy phenotypes. For a subset of patients with a 16p13.11 deletion, we show a consistent reduction of expression for included genes, suggesting that haploinsufficiency might contribute to pathogenicity. We also investigated another possible mechanism of pathogenicity by using hybridization-based capture and next-generation sequencing of the homologous chromosome for ten 16p13.11-deletion patients to look for unmasked recessive mutations. Follow-up genotyping of suggestive polymorphisms failed to identify any convincing recessive-acting mutations in the homologous interval corresponding to the deletion. The observation that two of the 16p13.11 deletions were larger than 2 Mb in size led us to screen for other large deletions. We found 12 additional genomic regions harboring deletions > 2 Mb in epilepsy patients, and none in controls. Additional evaluation is needed to characterize the role of these exceedingly large, non-locus-specific deletions in epilepsy. Collectively, these data implicate 16p13.11 and possibly other large deletions as risk factors for a wide range of epilepsy disorders, and they appear to point toward haploinsufficiency as a contributor to the pathogenicity of deletions.

Electroencephalography monitoring in critically ill children: current practice and implications for future study design.

PURPOSE: Survey data indicate that continuous electroencephalography (EEG) (CEEG) monitoring is used with increasing frequency to identify electrographic seizures in critically ill children, but studies of current CEEG practice have not been conducted. We aimed to describe the clinical utilization of CEEG in critically ill children at tertiary care hospitals with a particular focus on variables essential for designing feasible prospective multicenter studies evaluating the impact of electrographic seizures on outcome. METHODS: Eleven North American centers retrospectively enrolled 550 consecutive critically ill children who underwent CEEG. We collected data regarding subject characteristics, CEEG indications, and CEEG findings. KEY FINDINGS: CEEG indications were encephalopathy with possible seizures in 67% of subjects, event characterization in 38% of subjects, and management of refractory status epilepticus in 11% of subjects. CEEG was initiated outside routine work hours in 47% of subjects. CEEG duration was <12 h in 16%, 12-24 h in 34%, and >24 h in 48%. Substantial variability existed among sites in CEEG indications and neurologic diagnoses, yet within each acute neurologic diagnosis category a similar proportion of subjects at each site had electrographic seizures. Electrographic seizure characteristics including distribution and duration varied across sites and neurologic diagnoses. SIGNIFICANCE: These data provide a systematic assessment of recent CEEG use in critically ill children and indicate variability in practice. The results suggest that multicenter studies are feasible if CEEG monitoring pathways can be standardized. However, the data also indicate that electrographic seizure variability must be considered when designing studies that address the impact of electrographic seizures on outcome.