SCN1A Gene Mutations in Indian Children With Epilepsy: Single Center Experience

Objective: To study prevalence of SCN1A gene mutations in complex seizure disorders. Methods: Retrospective laboratory based study on samples sent for molecular diagnosis in complex seizure disorders. Exome sequencing was performed. Phenotype- genotype correlation was done for patients showing variants in SCN1A gene. Results: 364 samples were evaluated; of which, 54% were of children below 5 years of age. SCN1A mutations were seen in 50 samples of patients with complex seizure disorders; 44 variants were identified. Types of seizure disorders commonly associated were Dravet syndrome and genetic epilepsy with febrile seizures. Conclusions: SCN1A mutations are common in complex seizure disorders, especially Dravet syndrome. Early identification of SCN1A gene in etiology is important for selection of correct antiepileptic and counselling.

Heterogeneidad clínica y molecular en los trastornos asociados con CDKL5 / Clinical and molecular heterogeneity in CDLK5 disorders

Resumen Introducción: El síndrome por deficiencia de CDKL5 es originado por variantes patogénicas en el gen CDKL5, con un espectro clínico variable que va desde pacientes con características del trastorno del espectro autista hasta epilepsia de inicio temprano y refractaria al tratamiento. Inicialmente fue considerado como una forma atípica de síndrome de Rett. Casos clínicos: Presentamos tres pacientes no relacionadas, evaluadas por retraso global del desarrollo y epilepsia refractaria. Los tres casos eran hemicigotos a una variante patógena de CDKL5. En una paciente se realizó panel de 306 genes asociados con epilepsia; en las otras dos se realizó microarreglo genómico comparativo. Las características clínicas y los hallazgos en el electroencefalograma y la resonancia magnética cerebral se han descrito clásicamente en el espectro de manifestaciones de este síndrome. Conclusiones: El síndrome por deficiencia de CDKL5 representa un reto para los médicos, ya que en muchos casos las manifestaciones clínicas y los estudios electroencefalográficos y de neuroimagen pueden ser inespecíficos. Debe sospecharse este síndrome ante la presencia de retraso global del desarrollo, fenotipo conductual autista y epilepsia, asociado o no con dismorfias. Dada la similitud entre diversas encefalopatías epilépticas, se deben solicitar paneles multigénicos que incluyan la secuenciación y el análisis de duplicación/deleción en los que se contemple este gen y sus posibles diagnósticos diferenciales, aunque sin olvidar la utilidad de las técnicas genómicas en casos poco claros.

Abstract Background: CDKL5 deficiency syndrome is caused by pathogenic variants in the CDKL5 gene, with a variable clinical spectrum ranging from patients with characteristics of autism spectrum disorder to early-onset epilepsy refractory to treatment. Initially, until the gene was discovered, it was considered an atypical form of Rett syndrome. This study aimed to describe the clinical and molecular heterogeneity in CDLK5 disorders among three female patients with CDKL5 pathogenic variants. Case reports: We reported three unrelated Mexican female patients evaluated for global developmental delay and epilepsy. All three cases were hemizygotes to a CDKL5 pathogenic variant. In one patient, we performed a 306 gene panel associated with epilepsy. In the other two cases, a human genomic microarray was performed. We describe their clinical features electroencephalogram and brain magnetic resonance evaluations. Conclusions: CDKL5 deficiency syndrome represents a challenge for clinicians since the clinical manifestations, electroencephalographic and neuroimaging studies can be non-specific. This syndrome should be suspected in the presence of global developmental delay, autistic behavioral phenotype and epilepsy, associated or not with dysmorphia. Given the similarity between various epileptic encephalopathies, multigene panels including sequencing and duplication/deletion analysis should be requested in which this gene and its possible differential diagnoses are considered, without forgetting the usefulness of genomic techniques in unclear cases.

Global developmental delay and epileptic encephalopathy caused by SPTAN1 gene mutations in 3 cases and literature review / 中华神经科杂志

Objective:To summarize the clinical manifestations, gene variations,and treatment of cases with SPTAN1 gene variations characterized by global developmental delay or epileptic encephalopathy. Methods:Three patients with SPTAN1 gene mutations which caused developmental epileptic encephalopathy type 5 admitted to the Department of Pediatrics, Xiangya Hospital, Central South University from August 2019 to September 2021 were collected. The studies till December 2021 were searched with keywords of " SPTAN1" and "developmental and epileptic encephalopathy 5" in both English and Chinese databases of China National Knowledge Infrastructure, Wanfang, Online Mendelian Inheritance in Man, and PubMed. The clinical manifestations, genetic variations, treatments and prognosis of patients with SPTAN1 gene variations were summarized. Results:All 3 patients presented with global developmental delay, infant onset. Patient 1 showed early-onset epileptic encephalopathies and microcephaly. Patient 2 had an atrial septal defect. Cranial magnetic resonance imaging (MRI) of patient 3 showed cerebellar hypoplasia.Antiepileptic seizure therapy was partially effective, but failed to control the spasm. Development was slightly improved after rehabilitation training and other treatments, but still lagged behind the children of the same age. The SPTAN1 gene mutations of the 3 cases were heterozygous mutations, c.6923_6928dup, c.6619_6621delGAG and c.6749T>C, respectively. c.6749T>C was not reported in the previous literature. Thirteen case reports, including 69 patients, were collected. Sixty-seven patients had heterozygous mutations, inherited in an autosomal dominant fashion, including 35 missense mutations, 12 deletion mutations, 11 repetition mutations, 9 nonsense mutations, and the rest 2 patients had compound heterozygous missense mutations. A total of 38 different variation sites were reported. The phenotypes of 69 patients from the previous studies mainly included intellectual impairment (32/69), seizures (30/69), developmental delay (28/69), progressive microcephaly (27/69), hypotonia (23/69), poor visual attention (15/69), spastic quadriplegia (9/69), and gastrointestinal abnormalities (7/69). The primary type of seizures was epileptic spasm. Cranial MRI abnormalities mainly included cerebellar and brainstem atrophy, corpus callosum dysplasia, myelin dysplasia, and brain atrophy. Previous reports showed that a variety of anti-seizure drugs were effective for epileptic seizures. The prognosis varied greatly. Severe cases could be fatal, and mild cases only manifested as mild mental retardation or movement disorders. Conclusions:SPTAN1 gene mutation leads to developmental epileptic encephalopathy type 5, the phenotypes of which include intellectual impairment, global developmental delay, infantile spasms, and head deformity.Antiepileptic drugs and functional training can improve the symptoms, but the prognosis is still poor. This study expands the SPTAN1 gene variant spectrum, enriches the mutant spectrum of SPTAN1 gene associated with developmental epileptic encephalopathy type 5.

Clinical and genetic analysis of children with developmental and epileptic encephalopathy 8 caused by ARHGEF9 gene variants / 中华神经科杂志

Objective:To analyze the clinical characteristics and genetic variation of 2 children with developmental and epileptic encephalopathy 8 (DEE8).Methods:Whole-exome sequencing (WES) was performed to determine the potential variants in the probands. Candidate variants identified by WES were validated by Sanger sequencing and quantitative real-time polymerase chain reaction. X chromosome inactivation (XCI) detection was performed in the proband 1′s mother and proband 2 to detect the allelic expression difference of ARHGEF9. Results:Both of the cases showed global developmental delay. Proband 1 presented with delayed motor and speech development, intellectual disability, and seizures. Electroencephalography of proband 1 showed slow background activity, with spikes, spike and waves in bilateral frontal and midline regions during sleep. While proband 2 showed delay in acquisition of language, motor skills, and cognition, but no seizures. It was identified that proband 1 carried a novel maternally derived heterozygous splicing variant (c.925-2A>T) in ARHGEF9 by WES, which was verified in Sanger sequencing. The XCI in proband 1′s mother was observed, and the expression ratio of mutant ARHGEF9 and wild-type was 0∶100%. A novel exon 3-10 heterozygous deletion of ARHGEF9 was identified in proband 2, and this variant was not found in his unaffected parents. Conclusions:DEE8 disorders are relatively rare. Most of the patients have varying degrees of neurodevelopmental phenotype, but epilepsy is not a specific clinical manifestation. ARHGEF9 gene deletion and splicing variation may be the genetic cause of the 2 probands, and above findings have enriched the spectrum of variation and phenotype of DEE8.

Clinical characteristics and gene analysis of SMC1A gene related disorders / 中华神经科杂志

Objective:To analyze the clinical characteristics and genetic features of SMC1A gene related disorders. Methods:The data of 5 children with SMC1A gene variants were collected from Children′s Hospital of Fudan University from February 2018 to January 2022. The clinical features, electroencephalogram (EEG), brain imaging and gene testing results were summarized. Results:Among the 5 patients, 4 are females and 1 is male. Two female cases are siblings. One boy had dysmorphic features, consisting of bilateral ptosis, synophrys, a short nose and upturned nasal tip. He also had patent foramen ovale plus atrial septal defect, unilateral cryptorchidism and microcephaly. Three cases had microcephaly. Two girls had patent foramen ovale, and 2 girls had microcephaly. Four cases had epilepsy, and age at seizure onset ranged from 2 to 52 months. Multiple seizure types were observed, including bilateral tonic clonic seizures in 2 patients, and focal seizures in 3 patients. The seizures in 3 cases were in cluster. All patients had developmental delay, including 1 patient with mild and 4 patients with moderate to severe developmental delay. Three patients had slow background activity in EEG. Interictal EEG showed abnormal discharges in 4 patients, including focal discharges in 3 cases and generalized discharges in 1 case. Brain magnetic resonance imaging was normal in 3 patients and showed mild cortical thickening in 1 case. All cases harbored 4 SMC1A gene variants, including 2 missense variants and 2 frameshift variants (c.580_587del, c.2699delG, c.3362G>A, c.1486C>T). Three cases harbored heterozygous SMC1A variants and 2 cases carried somatic mosaic SMC1A variants with 17.5% and 88.1% mosaicism in peripheral blood. The follow-up lasted for 3 months to 4 years. The epilepsy was refractory in 2 cases. During the follow-up, all cases had very slow developmental progress or developmental retardation. All cases had different levels of growth retardation. The scores of Cornelia de Lange syndrome (CdLS) phenotypes in 5 cases were 2-6. One case had the combined phenotypes of atypical CdLS and developmental epileptic encephalopathy (DEE). The phenotype was atypical CdLS in 1 case and DEE in 1 case. The phenotypes of 2 cases with SMC1A missense variants were mild, manifesting as non-refractory epilepsy and moderate to severe developmental delay. Conclusions:All of cases with SMC1A gene variants have developmental delay. Most of the patients have clusters of seizures and some dysmorphisms. The phenotypes of SMC1A gene related disorders are diverse. Except CdLS and DEE, there are some patients with mild phenotype due to missense variants of SMC1A gene.

Clinical characteristics of a case of developmental and epileptic encephalopathy caused by PPP3CA gene mutation and literature review / 中华神经科杂志

Objective:To improve clinicians′ understanding of developmental and epileptic encephalopathy (DEE) caused by PPP3CA gene mutation. Methods:Clinical data of a patient with DEE diagnosed in the First Department of Neurology, Hebei Children′s Hospital in September 2018 were collected. The whole-exome sequencing of the proband′s family was performed, and the characteristics of gene mutation were analyzed. Literature review was carried out based on the reported cases related to PPP3CA gene. Results:The proband, a 3 months and 20 days old girl, was admitted to the hospital with a history of paroxysmal confusion with extremities shaking for 2 days. The clinical manifestations included frequent epilepsy seizures and hypoevolutism. Brain magnetic resonance imaging showed that the bilateral frontotemporal extracerebral space was slightly wider. The video electroencephalography showed hyperarrhythmia and a cluster of spastic seizures. Whole exome sequencing of the family revealed that the proband had a heterozygous de novo frameshift truncating mutation in the PPP3CA gene: c.1255-1256delAG (p.Ser419Cysfs*31). From the establishment of the database to May 2022, 8 foreign literatures and 1 Chinese literature were retrieved, and a total of 21 children with PPP3CA gene mutation were reported, with clinical developmental delay, cognitive dysfunction and abnormal electroencephalography activity. Conclusions:The frameshift truncating mutation of the PPP3CA gene (c.1255-1256delAG) is the hereditary etiology of this patient. For cases of frequent seizures with poor efficacy of antiepileptic drugs, and developmental delay, genetic testing should be performed to confirm diagnosis and treatment.

A case of developmental epileptic encephalopathy type 67 caused by CUX2 gene mutation and literature review / 中华神经科杂志

Objective:To summarize the clinical phenotype and CUX2 gene variation characteristics of developmental epileptic encephalopathy type 67 confirmed by whole exome sequencing. Methods:Clinical data of 1 case diagnosed as CUX2 gene mutations related developmental epileptic encephalopathy type 67 in the Children′s Hospital Affiliated to Zhengzhou University in January 2021 were collected, the patient′s clinical characteristics, genetic testing, head imaging, electroencephalogram results and treatment were summarized, and the patient was regularly followed-up every 3 months. At the same time, the domestic and foreign literatures on epileptic encephalopathy caused by CUX2 gene mutation were reviewed. Results:The proband was a 6 years and 4 months old girl. The main clinical manifestations included focal origin progression to bilateral tonic-clonic seizures, retardation of intellectual, language, and motor development, autistic behavior, hyperactivity disorder, and involuntary hand clapping. The video electroencephalogram showed extensive spiny slow wave and multi-spiny slow wave emission in waking and sleeping stages, and spiny slow wave and spiky slow wave emission in bilateral anterior head in sleeping stage. Brain magnetic resonance imaging (MRI) plain scan and T 2-fluid attenuated inversion recovery (T 2-FLAIR) thin layer scan showed that the signal of the left hippocampus was higher than that of the right, and the left hippocampus was slightly swollen. One month later, the brain MRI and T 2-FLAIR were reexamined. The left hippocampal signal was still slightly higher and decreased, and the hippocampal volume was slightly reduced. Whole exome sequencing showed the CUX2 gene with c.1768G>A(p.Glu590Lys) heterozygous missense variant, which was a reported de novo pathogenic variant and both of her parents were wild-type. A total of 10 cases of new heterozygous missense variants in CUX2 gene [c.1768G>A (p.Gelu590Lys)] were reported in 4 literatures. No relevant cases have been reported in China. Conclusions:Developmental epileptic encephalopathy type 67 is relatively rare. The main clinical features are seizures, global developmental delay, movement disorders, athetosis, autism and hyperactivity disorder. The heterozygous missense variant c.1768G>A (Glu590Lys) of CUX2 gene maybe the genetic cause of this case.

Developmental and epileptic encephalopathy with dyskinesia caused by the FRRS1L gene mutation: a case report and literature review / 中华实用儿科临床杂志

The clinical characteristics and gene mutation profiles of a child who was treated in Xuzhou Children′s Hospital, Xuzhou Medical University in June 2022 due to developmental and epileptic encephalopathy (DEE) combined with dyskinesia caused by the FRRS1L gene mutation was analyzed retrospectively.A male case 1 year and 9 months old presented developmental delay since childhood, hypotonia at the age of 6 months, treatment-resistant seizures (focal clonic seizures) at the age of 1 year and 7 months that were unable to be controlled by antiepileptic drugs, and developmental regression and abnormal movements of the hands and feet during the attack.Whole exome sequencing showed 2 heterozygous variants (missense mutation and deletion mutation) in the FRRS1L gene of the child.The missense mutation c. 754C>T (p.R252C) located in the 4 th exon was inherited from his mother, and the deletion mutation c. 438_c.459del (p.I146fs*4) located in the 2 th exon was inherited from his father, thus constituting a compound heterozygous mutation.Through literature review, all 6 relevant literatures involving 31 children with DEE were published in foreign countries.They presented similar clinical manifestations to this case, but the genotypes were different, all of which were homozygous mutations.The FRRS1L gene mutation can lead to DEE, which is characterized by the autosomal recessive inheritance pattern, refractory epilepsy onset in infancy, developmental regression and prominent dyskinetic movements with hyperkinesia, and poor long-term prognosis.

Developmental epileptic encephalopathy associated with the CACNA1E gene mutation / 中华实用儿科临床杂志

One of the important causes of developmental epileptic encephalopathy (DEE) is the mutation of ion channel genes, including the mutation of the CACNA1E gene. CACNA1E-related DEE cases were first reported in 2018.The mutation types include new missense mutations, nonsense mutations and frameshift mutations, but the correlation between mutation sites and types with the phenotype of DEE is not clear.This review aims to summarize the reported CACNA1E-related DEE cases, and explore the correlation between the clinical phenotype of CACNA1E-related DEE and gene mutation sites and mutation types.Meanwhile, possible pathogenesis of CACNA1E-related DEE and the progress of drug intervention were reviewed to provide references for the diagnosis and precise treatment of DEE.

Research progress of voltage-gated Calcium channel gene mutations associated with epilepsy in children / 中华实用儿科临床杂志

Abnormal expression and dysfunction of voltage-gated Calcium channels (VGCCs) can give rise to a variety of neurological disorders in children, including epilepsy, migraine and ataxia.In the past, only CACNA1A, CACNA1H, CACNA2D2 and CACNB4 were considered associated with epilepsy in children.In recent years, an increasing number of VGCCs gene associated with epilepsy in children have been found, especially developmental and epileptic encephalopathy genes.This study aims to review the research progress of VGCCs gene mutations associated with epilepsy in children.

Clinical and genetic study of developmental and epileptic encephalopathy in argentinean pediatric patients / Estudio clínico y genético de encefalopatía epiléptica y del desarrollo en pacientes pediátricos argentinos

Abstract Introduction: The aim of this study was to extend our knowledge of the genetic background of Argentinean pediatric patients with developmental and epileptic encephalopathy (DEE) applying a next generation sequencing (NGS) panel. Methods: Thirty one patients with DEE were studied, including these phenotypes: Dravet syndrome (n:7), Dravet like syndrome (n:3), West syndrome (WS) (n:6), WS that evolved to Lennox-Gastaut syndrome (LGS) (n:4), epilepsy of infancy with migrating focal seizures (n:2), continuous spikes and waves during slow sleep evolving to LGS (n:1), LGS (n:1), myoclonic status in non-progressive encephalopathy (n:1), myoclonic atonic epilepsy (n:1), epileptic encephalopathy with multifocal spikes (n:1) and unclassified epileptic encephalopathy (n:4). Fifty-two genes frequently associated with DEE were studied by NGS in genomic DNA from peripheral blood. Results: Relevant variants were detected in 12 cases; 6 novel pathogenic or likely pathogenic variants, 6 previously reported as pathogenic and 1 variant of unknown sig nificance. Single-nucleotide heterozygous variants were identified in the SCN1A (5), GABRG2 (1), STXBP1 (2) genes, a mosaic variant in SCN2A (1) and a homozygous variant in SCN1B (1). Additionally, a heterozygous deletion involving the SCN1A, SCN2A and SCN3A genes (1), and the most frequent triplet repeat expansion in the ARX gene (1) were detected. Discussion: Genetic diagnosis was made in 39% of patients. We emphasize the importance of considering mosaic variants, copy number variants and hereditary forms when designing and interpreting molecular studies, to optimize diagnosis and management of patients. Approximately 42% of the de tected variants were novel, expanding the knowledge of the molecular basis of DEEs in Latin-American patients.

Resumen Introducción: El objetivo del estudio fue ampliar el conocimiento de las bases moleculares de las encefalopatías epilépticas y del desarrollo (EED) en pacientes pediátricos argentinos aplicando un panel de secuenciación de nueva generación (NGS). Métodos: Se analizaron 31 pacientes con los fenotipos clínicos de síndrome de Dra vet (n:7), síndrome símil Dravet (n:3), síndrome de West (SW) (n:6), SW que evoluciona a síndrome de Lennox Gastaut (SLG)(N:4), epilepsia de la infancia con crisis focales migratorias (n:2), actividad de punta onda continua durante el sueño que evolucionan a SLG (n:1), SLG (n:1), encefalopatía no progresiva con estatus mioclónico (n:1), epilepsia mioclónica atónica (n:1), encefalopatía epiléptica con espigas multifocales (n:1) y encefalopatía epiléptica indeterminada (n:4). Se estudiaron los 52 genes más frecuentemente asociados a EED a través de NGS, en ADN extraído de sangre periférica. Resultados: Se identificaron variantes relevantes en 12 casos, de las cuales 5 fueron nuevas y 6 previamente reportadas como patogénicas o posiblemente patogénicas, mien tras que una variante fue clasificada como de significado incierto. Variantes heterocigotas, de nucleótido único, se identificaron en los genes SCN1A (5), GABRG2 (1), STXBP1 (2), una variante en mosaico en SCN2A (1) y otra homocigota en SCN1B (1). Además, se detectó una deleción que involucra a los genes SCN1A, SCN2A y SCN3A (1) y la expansión de repeticiones de tripletes más frecuente en el gen ARX (1). Discusión: Se alcanzó el diagnóstico molecular en el 39% de los pacientes. Remarcamos la importancia de considerar variantes en mosaico, variantes en el número de copias y formas heredadas al momento de diseñar e interpretar los estudios moleculares, de tal forma de optimizar el diagnóstico y seguimiento de los pacientes con EED. Cabe destacar, que el 42% de las variantes detectadas fueron nuevas, ampliando nuestro conocimiento sobre las bases mole culares de las EED en población latino americana.

Encefalopatías epilépticas de inicio en recién nacidos y lactantes / Epileptic encephalopathies of onset in neonates and infants

Resumen Recientemente la Liga Internacional contra la Epilepsia (ILAE) socializó la clasificación propuesta para síndromes epilépticos de inicio neonatal y hasta los primeros 2 años de edad, dividiéndolos en síndromes epilépticos autolimitados y las encefalopatías epilépticas y del desarrollo (DEEs). En esta revisión nos dedicaremos a las DEEs, definidas como trastornos donde existe deterioro del desarrollo relacionado tanto con la etiología subyacente independiente de la actividad epileptiforme como con la encefalopatía epiléptica. Estas incluyen en el período neonatal la encefalopatía epiléptica infantil temprana o síndrome de Ohtahara y la encefalopatía mioclónica temprana, ahora agrupadas bajo la denominación de encefalopatías epilépticas y del desarrollo infantil temprano (EIDEE). El síndrome de espamos epilépticos infantiles, la epilepsia de la infancia con crisis migratorias y el síndrome de Dravet forman parte de las encefalopatías de inicio en el lactante. La importancia del reconocimiento temprano de las encefalopatías epilépticas radica no solo en el control de las crisis epilépticas, sino en detener el deterioro intentando cambiar el curso de la enfermedad. Es fundamental conocer la etiología evitando medicamentos que puedan exacerbar las crisis y empeorar el curso, aplicando medicina de precisión así como identificando pacientes candidatos a cirugía temprana de epilepsia.

Abstract The International League Against Epilepsy (ILAE) recently socialized the proposed classification for epileptic syndromes of neonatal onset and up to the first 2 years of age, dividing them into self-limited epileptic syndromes and epileptic and developmental encephalopathies (DEEs). In this review we will focus on DEEs, defined as disorders in which there is developmental impairment related to both the underlying aetiology independent of epileptiform activity and epileptic encephalopathy. These include early infantile epileptic encephalopathy or Ohtahara syndrome and early myoclonic encephalopathy in the neonatal period, now grouped under the name of epileptic and early childhood developmental encephalopathies (EIDEE). Infantile epileptic spasms syndrome, childhood epilepsy with migratory crises and Dravet syndrome are part of the infant-onset encephalopathies. The importance of early recognition of epileptic encephalopathies lies not only in the control of epileptic seizures, but also in stopping deterioration by trying to change the course of the disease. It is essential to know the etiology, avoiding medications that can exacerbate seizures and worsen the course, applying precision m edicine as well as identifying candidate patients for early epilepsy surgery.

Advances on the spectrum of neurological diseases related to the CACNA1A gene / 中华实用儿科临床杂志

The CACNA1A gene encodes a voltage-gated calcium channel of the pore-forming protein, which has important functions in the central nervous system.The CACNA1A gene mutation can lead to a variety of neurological diseases, including familial hemiplegic migraine 1, spinocerebellar ataxia 6, episodic ataxia 2 and early infantile epileptic encephalopathy 42.Overlapping phenotypes could be observed in a small number of patients.This review summarized the clinical and genetic characteristics of the CACNA1A gene mutation.

Genotype and phynotype of DNM1 gene variants related developmental epileptic encephalopathy / 中华实用儿科临床杂志

Objective:To summarize the clinical features of developmental epileptic encephalopathy children with DNM1 gene variants. Methods:The genotypes and clinical features of 15 children with DNM1 variants related epilepsy in the Department of Pediatrics, Peking University First Hospital from June 2017 to October 2021 were retrospectively analyzed. Results:A total of 8 male and 7 female epilepsy patients with DNM1 gene variants with the age of seizure onset ranging from 15 days to 22 months were recruited, median age was 8 months.All cases belonged to de novo heterozygous variants of the DNM1 gene, including 13 cases of missense variants, 1 case of frame shift variant and 1 case of nonsense variant, 8 cases of ectopic sites have not been reported.Multiple seizure types were observed, including epileptic spasms in 15 patients, focal seizure in 9 patients, atypical absence seizure in 2 patients and tonic seizure in 2 patients.There were various types of seizures in 7 children.Nine cases occurred as infantile spasm for the first time.All 15 patients showed varied degrees of development delay, among them, 11 cases had developmental retardation before epilepsy.Three patients had slow rhythm of electroencephalogram background activity, the electroencephalography showed hypsarrhythmia in 13 patients; clinical seizures were detected in 8 cases, among them, epileptic spasms were captured in 7 patients, tonic seizure was captured in 1 patient.Widened frontotemporal subarachnoid space, cerebral atrophy, and corpus callosum dysplasia were examined in 6, 2 and 3 patients by cranial magnetic resonance imaging, respectively.All 15 cases were diagnosed as developmental epileptic encephalopathy, of which 13 cases were consistent with infantile spasms.The age of the last follow-up ranged from 1 year old to 7 years old.After multi-antiepileptic drug treatment, 2 patients were remission, 1 patient(small size of identical twins) died of severe pneumonia at the age of 2 years, and 12 patients still had intermittent seizures, of which 1 patient was transformed from infantile spasms to Lennox-Gastaut syndrome. Conclusions:The onset age of developmental epileptic encephalopathy caused by the DNM1 gene variant usually begins in the infantile period, the peak onset age was 8 months.The main types of seizures include epileptic spasms and focal seizures, developmental retardation can occur before seizures.The clinical manifestations are mostly infantile spasms syndrome, and some children can be transformed into Lennox-Gastaut syndrome.

Case report of early-onset epileptic encephalopathy caused by compound heterozygous mutation of the WWOX gene / 中华实用儿科临床杂志

Clinical data of a case with early-onset epileptic encephalopathy admitted in the Department of Neuroendocrinology, Jinan Children′s Hospital in April 2020 were retrospectively analyzed.A 1-month-old male patient was hospitalized for convulsion for 4 days.The child had repeated seizures in the form of tonic and tonic-spasm seizures, accompanied by feeding difficulties, slow weight gain, and overall developmental delay.Electroencephalogram showed multifocal discharge, atypical hypsarrhythmia, and brain magnetic resonance imaging showed delayed myelination.The whole exome sequencing showed compound heterozygous mutation of the WWOX gene.Topiramate, Levetiracetam and Valporate were ineffective to this case.Genetic testing should be performed timely in patients with early-onset epileptic encephalopathy and overall developmental delay to make a clear etiology and prognosis, thus guiding prenatal diagnostics and genetic counseling.

Early-onset epileptic encephalopathy caused by the UBA5 gene mutation: a case report and literature review / 中华实用儿科临床杂志

Objective:To explore the clinical and genetic characteristics of a case of early-onset epileptic encephalopathy caused by the UBA5 gene mutation and to review relevant literatures. Methods:The clinical characte-ristics and genetic data of a child with the UBA5 gene mutation in the Department of Pediatrics, the Third Affiliated Hospital of Zhengzhou University in June 2020 were retrospectively analyzed.Clinical characteristics and gene variation characteristics of the disease were reviewed in the domestic and foreign databases. Results:(1) The female patient presented infantile spasms at the age of 4 months.Electroencephalogram(EEG) suggested hypsarrhythmia and she was not responsive to a variety of anti-epileptic drugs.Besides, the patient showed severe cognitive and motor development delay, hypotonia, and microcephaly.The results of whole exome sequencing showed that the compound heterozygous mutation of UBA5 gene: exon 3 c. 214C>T (p.R72C) and exon 9 c. 844_c.845 insA (p.Y282Xfs*1), her father carries c. 214C>T mutation and her mother carries c. 844_c.845 INSA mutation.(2) To December 2020, a total of 15 cases of early-onset epileptic encephalopathy caused by the UBA5 gene mutation have been reported abroad.The main clinical manifestations were uncontrollable spasms, abnormal EEG findings, hypotonia, severe cognitive and movement disorders, microcephaly, and brain atrophy.A total of 11 mutation sites of the UBA5 gene were found, all belonging to the autosomal recessive inheritance, of which c. 1111G>A was the most common. Conclusions:The UBA5 gene mutation can lead to early-onset epileptic encephalopathy, which belongs to the autosomal recessive inheritance.It is featured by the early onset, uncontrollable seizures and poor long-term prognosis.

Clinical features and genetic analysis of the early-onset epileptic encephalopathy caused by sodium channel mutations / 中华实用儿科临床杂志

Objective:To explore the clinical phenotype characteristics of early-onset epileptic encephalopathy (EOEE) caused by sodium channel mutations.Methods:A retrospective study was used.A total of 52 EOEE patients treated in the Department of Neurology, Children′s Hospital of Fudan University and Department of Neurology, Wuhan Children′s Hospital, Tongji Medical College, Huazhong University of Science & Technology from June 2016 to June 2019 were recruited.Peripheral blood samples of 52 patients and their parents were collected for analyzing pathogenic mutations by the next generation sequencing and copy number variations of whole exons in family. Chi- square test was used to compare seizure control data among different voltage-gated sodium channel α1 subunit ( SCN1A) mutation types. Results:A total of 35/52 cases (67.3%) were diagnosed as Dravet syndrome, 3/52 cases (5.8%) were West syndrome, and 14/52 cases (26.9%) were non-symptomatic EOEE.The electroencephalogram (EEG) findings showed a large number of multifocal spikes, spike-slow waves, sharp waves, and sharp-slow waves.A total of 45/52 cases (86.5%) showed normal brain magnetic resonance imaging(MRI), 1 case had slightly widened bilateral frontal sulcus, 1 case had widened bilateral temporal pole and frontal top subarachnoid space, and the remaining 5 cases had widened extracerebral space and slightly larger ventricles.Thirteen cases were re-examined with brain MRI, and 3 cases had mild brain atrophy.A total of 43/52 cases (82.7%) were examined with SCN1A gene mutations, of which 28/52 cases (53.8%) were missense mutations, 5/52 cases (9.6%) were nonsense mutations, 7/52 cases (13.5%) were frameshift mutations and 3/52 cases (5.8%) were splice site mutations.A total of 3/52 cases (5.8%) had SCN2A mutations, of which 2/52 cases (3.8%) were missense mutations, and 1/52 case (1.9%) was a frameshift mutation, 1/52 cases (1.9%) carrying the missense mutation of the SCN3A gene.A total of 5/52 cases (9.6%) had missense mutations of the SCN8A gene.After an average of 1-year follow-up, a total of 13/52 cases (25.0%) had more than 1-year control of seizure, of which 6/52 cases (11.5%) with seizure control for more than 2 years, and 4/52 cases (7.7%) with more than 3-year control.Children carrying SCN1A missense mutations were relatively easier to be controlled for seizures than those carrying SCN1A truncation mutations (nonsense mutations+ frameshift mutations) ( P<0.05). In 5 children carrying SCN8A mutations, 2 cases of them had seizures control for more than 1 year after adding Oxcarbazepine, but the improvement of mental motor function was not obvious. Conclusions:In children with EOEE associated with sodium channel gene mutations, SCN1A, SCN2A, SCN3A, and SCN8A mutations were pathogenic factors.Among them, SCN1A was the most common pathogenic gene for EOEE, with the mutation rate of 82.7%.Dravet syndrome was the most common clinical phenotype of EOEE associated with sodium channel gene mutations.Epileptic seizures in children carrying SCN1A missense mutations were easier to be controlled than those with truncated mutation (nonsense mutations + frameshift mutations), suggesting that the gene mutation type was related to the degree of seizures control.Oxcarbazepine was effective in the treatment of EOEE with SCN8A gene mutations, indicating that the combination therapy using anti-epilepsy drugs can be applied to EOEE patients according to the type of gene function.

Epileptic encephalopathy caused by the RHOBTB2 gene mutation: a case report and literature review / 中华实用儿科临床杂志

Clinical data (including clinical phenotype and gene mutation characteristics) of a case of epileptic encephalopathy carrying the RHOBTB2 gene mutation treated at the Department of Pediatric Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University in June 2020 was analyzed retrospectively.Relevant literatures were reviewed as well.A male patient aged 3 months and 12 days presented with repeated convulsions for 2 days.The main symptoms included afebrile epileptic status, featuring eye deviation to the left, and limb tonic-clonic jerk lasting for about 30 minutes.Physical examinations showed that the child could not control his head and cried lowly.The whole exome sequencing data revealed a novel heterozygous variation in exon 7 of the RHOBTB2 gene: c.1448G>A(p.Arg483His). Seizures were controlled by the treatment of Levetiracetam combined with Topiramate, but remained growth retardation.The prognosis of epileptic encephalopathy caused by the RHOBTB2 gene mutation is poor, and most children have dyskinesia and microcephaly.

Case report of developmental epileptic encephalopathy caused by UBA5 gene mutation and literature review / 中华实用儿科临床杂志

Objective:To summarize the clinical and gene mutation characteristics of a child with developmental epileptic encephalopathy (DEE) caused by ubiquitin-like modifier-activating enzyme 5( UBA5 )gene mutation, and to perform literature review. Methods:Clinical characteristics and genetic test results of a case of DEE treated in Department of Neurology, Xuzhou Children′s Hospital, Xuzhou Medical University, in March 2020 were retrospectively analyzed.Relevant literatures reporting DEE cases caused by UBA5 gene mutations published before June 2020 were searched in the PubMed, CNKI, Wanfang and other online databases with the following key words: epilepsy encephalopathy, developmental encephalopathy, epileptic encephalopathy, Developmental encephalopathy and UBA5. Results:A female case with 7 months and 23 days old presented epileptic spasms at 4 months of age, and the condition was uncontrolled by medication of adrenocorticotropic hormone (ACTH) and several antiepileptic drugs.The patient later progressed to recurrent, treatment-resistant seizures with arrested development, short stature, microcephaly, expressionless face, irritability, unsteady head, lack of follow-up vision, lack of laughing, and limb hypotonia.Whole exome sequencing revealed a missense mutation and a microdeletion in the UBA5 gene, and the missense mutation was paternal c. 722A>C (p.E241A), located in the 8 th exon region.The microdeletion deletion was maternally derived from the 5 th to 11 th exon, which constituted a compound heterozygous mutation.A total of 5 foreign literatures involving 18 children with DEE and 0 domestic literatures were retrieved.Combined with the present case, all 19 cases presented refractory seizures in the early infancy, and most of them were epileptic spasms (63.2%, 12/19 cases), followed by myoclonus (31.6%, 6/19 cases). The birth history of all children was unremarkable, and they later presented developmental disabilities at varying degrees, mainly including microcephaly (94.7%, 18/19 cases), lack of follow-up vision (89.5%, 17/19 cases), and short stature (94.7%, 18/19 cases), intellectual disabilities (89.5%, 17/19 cases), movement disorders (84.2%, 16/19 cases) and hypotonia (100.0%), 13/19 cases (68.4%) died.EEG results mainly revealed normal or hypsarrhythmia, but 1 case presented suppression- burst.Brain magnetic resonance imaging (MRI) findings mainly included delayed myelination (47.4%, 9/19 cases), brain atrophy (52.6%, 10/19 cases), and thin corpus callosum (26.3%, 5/19 cases). Conclusions:Children with UBA5 gene mutations often have refractory seizures in the early infancy, which are mainly epileptic spasms.They also show severe psychomotor developmental delay, microcephaly and dystonia, with an extremely poor prognosis.Brain MRI suggested varying degrees of myelin dysplasia, brain trophy, and thin corpus callosum.For cases with the above clinical manifestations, genetic testing should be considered to confirm the diagnosis.

Congenital disorder of glycosylation caused by de novo variant of SLC35A2 gene: a case report / 中华神经科杂志

Congenital disorder of glycosylation (CDG) is a group of genetic metabolic diseases involving multiple organs. A case of CDG caused by SLC35A2 gene mutation was diagnosed. The clinical characteristics included spasms, developmental retardation and multiple malformations. Video-electroencephalogram showed dysrhythmia. A de novo heterozygous missense mutation of SLC35A2 gene was detected by whole exome sequencing: c.844G>A (p.Gly282Arg). It was predicted to be likely pathogenic according to American College of Medical Genetics and Genomics guidelines which had not been reported in China.