Dissecting genetics of spectrum of epilepsies with eyelid myoclonia by exome sequencing.

OBJECTIVE: Epilepsy with eyelid myoclonia (EEM) spectrum is a generalized form of epilepsy characterized by eyelid myoclonia with or without absences, eye closure-induced seizures with electroencephalographic paroxysms, and photosensitivity. Based on the specific clinical features, age at onset, and familial occurrence, a genetic cause has been postulated. Pathogenic variants in CHD2, SYNGAP1, NEXMIF, RORB, and GABRA1 have been reported in individuals with photosensitivity and eyelid myoclonia, but whether other genes are also involved, or a single gene is uniquely linked with EEM, or its subtypes, is not yet known. We aimed to dissect the genetic etiology of EEM. METHODS: We studied a cohort of 105 individuals by using whole exome sequencing. Individuals were divided into two groups: EEM- (isolated EEM) and EEM+ (EEM accompanied by intellectual disability [ID] or any other neurodevelopmental/psychiatric disorder). RESULTS: We identified nine variants classified as pathogenic/likely pathogenic in the entire cohort (8.57%); among these, eight (five in CHD2, one in NEXMIF, one in SYNGAP1, and one in TRIM8) were found in the EEM+ subcohort (28.57%). Only one variant (IFIH1) was found in the EEM- subcohort (1.29%); however, because the phenotype of the proband did not fit with published data, additional evidence is needed before considering IFIH1 variants and EEM- an established association. Burden analysis did not identify any single burdened gene or gene set. SIGNIFICANCE: Our results suggest that for EEM, as for many other epilepsies, the identification of a genetic cause is more likely with comorbid ID and/or other neurodevelopmental disorders. Pathogenic variants were mostly found in CHD2, and the association of CHD2 with EEM+ can now be considered a reasonable gene-disease association. We provide further evidence to strengthen the association of EEM+ with NEXMIF and SYNGAP1. Possible new associations between EEM+ and TRIM8, and EEM- and IFIH1, are also reported. Although we provide robust evidence for gene variants associated with EEM+, the core genetic etiology of EEM- remains to be elucidated.

Brivaracetam in treating epileptic encephalopathy and refractory focal epilepsies in patients under 14 years of age.

OBJECTIVES: To analyze the efficacy and safety of Brivaracetam in pediatric patients with epileptic encephalopathy or unresponsive focal epilepsy. MATERIALS & METHODS: This retrospective study included eight pediatric patients with EE or unresponsive focal epilepsy. Inclusion criteria: (1) ≤14 years, (2) history of refractory epilepsy, (3) at least one month of continuous therapy with BRV, and (4) at least six months of follow-up. Exclusion criteria: (1) variation of concomitant antiepileptic drugs during the previous and/or subsequent four weeks of the BRV introduction, (2) levetiracetam in therapy, (3) epilepsy secondary to the progressive cerebral disease, tumor, or any other progressive neurodegenerative diseases, and (4) a status epilepticus a month before screening or during the baseline period. The efficacy of BRV was defined as ≥50% of seizure frequency reduction at the end of the follow-up, compared to baseline. RESULTS: All patients showed ≥50% seizure frequency reduction, of whom 37.5% were seizure-free, 25% had a frequency reduction of ≥75%, and 37.5% had frequency reduction of ≥ 50%. All patients with an epilepsy onset >12 months and epilepsy duration of ≤6 years were seizure-free. The maximum effect was achieved at 2 mg/kg/day, and focal seizures revealed a better response than epileptic encephalopathy. A remarkably positive effect of the Brivaracetam was noticed in patients with encephalopathy regarding the status epilepticus during sleep; however, no relevant side-effects were noted. CONCLUSION: Brivaracetam was an effective and well-tolerated treatment in pediatric patients with epileptic encephalopathy or unresponsive focal epilepsy, especially for the epilepsy onset >12 months and the epilepsy duration ≤6 years. The total effect was not dose-dependent. Brivaracetam could represent an indication of encephalopathy regarding the status epilepticus during sleep.

Low-grade tumour over the left temporal neocortex and ictal asystole: network and surgical implications.

We describe a patient with focal epilepsy characterized by ictal asystole episodes and low-grade tumour over the left temporal neocortex. Non-invasive pre-surgical evaluation showed an epileptogenic zone extended beyond the low-grade tumour. This extension was confirmed by intraoperative electrocorticography. One-stage surgery with anterior temporal lobe resection was performed. The patient was seizure-free after one year of follow-up. Detailed electroclinical and therapeutic reasoning with hypotheses defining epileptogenic and symptomatogenic networks are discussed.

Epilepsy, cerebral calcifications, and gluten-related disorders: Are anti-transglutaminase 6 antibodies the missing link?

PURPOSE: Gluten-related disorders (GRDs) are a group of immune-mediated diseases often associated to neurologic manifestations. Epilepsies with cerebral calcifications, with or without coeliac disease (CD), are rare neurological disorders characterized by childhood-onset focal seizures, often refractory to antiepileptic drugs. Transglutaminase 6 antibodies (anti-TG6) have been considered a biomarker for gluten-related ataxia and neuropathy, but their prevalence in epilepsies with cerebral calcifications is unknown. The aim of this study is to evaluate anti-TG6 prevalence in patients with epilepsies and cerebral calcifications. METHOD: this was a cross-sectional study conducted at five Italian epilepsy centres. The following groups were included. Group 1: nine patients with CD, posterior cerebral calcifications and epilepsy (CEC); group 2: nine patients with epilepsy and posterior cerebral calcifications, without CD; group 3: twenty patients with focal epilepsy of unknown etiology; group 4: twenty-two healthy controls (HC). All subjects were tested for serological evidence of anti-TG6 IgA and IgG. Differences among groups were analysed using χ ² test. RESULTS: anti-TG6 were present in 1/9 subjects (11%) of group 1, 2/9 subjects (22%) of group 2, 0/20 subjects in group 3, 3/22 (13.6%) of HC. No significant difference was found among the 4 groups. CONCLUSIONS: Anti-TG6 do not seem to be associated to epilepsies with cerebral calcifications.

Hemispherotomy in Rasmussen encephalitis: long-term outcome in an Italian series of 16 patients.

Surgical disconnection of the affected hemisphere is considered the treatment of choice for Rasmussen encephalitis (RE), however few data on long-term outcomes after disconnective surgery are available. We report on long-term seizure, cognitive and motor outcomes after disconnective surgery in 16 (8 M, 8 F) RE patients. Pre- and post-operative evaluations included long-term video-EEG monitoring, MRI, assessment of motor function, and cognitive evaluation. Hemispherotomy, by various techniques was used to obtain functional disconnection of the affected hemisphere. The patients, of median current age 23.5 years, range 12-33, were operated on between 1993 and 2009. Median age at disease onset was 5.8 years (range 3-11.4). Median time from seizure onset to surgery was 3.8 years, range 8 months to 21 years. Post-surgical follow-up was a median of 9.5 years, range 3-20. At surgery all patients were receiving two or more antiepileptic drugs (AEDs). All but three patients were seizure-free at latest follow-up. AEDs had been stopped in ten patients; in the remaining six AEDs were markedly reduced. Postural control improved in all patients. Gain in cognitive functioning was significantly (p=0.002) related to disease duration. The long-term outcomes, in terms of seizure control, motor improvement, and cognitive improvement provide important support for disconnective surgery as first choice treatment for RE.

Oxidative Stress and Erythrocyte Membrane Alterations in Children with Autism: Correlation with Clinical Features.

It has been suggested that oxidative stress may play a role in the pathogenesis of Autism Spectrum Disorders (ASD), but the literature reports somewhat contradictory results. To further investigate the issue, we evaluated a high number of peripheral oxidative stress parameters, and some related issues such as erythrocyte membrane functional features and lipid composition. Twenty-one autistic children (Au) aged 5 to 12 years, were gender and age-matched with 20 typically developing children (TD). Erythrocyte thiobarbituric acid reactive substances, urinary isoprostane and hexanoyl-lysine adduct levels were elevated in Au, thus confirming the occurrence of an imbalance of the redox status of Au, whilst other oxidative stress markers or associated parameters (urinary 8-oxo-dG, plasma radical absorbance capacity and carbonyl groups, erythrocyte superoxide dismutase and catalase activities) were unchanged. A very significant reduction of Na(+)/K(+)-ATPase activity (-66%, p<0.0001), a reduction of erythrocyte membrane fluidity and alteration in erythrocyte fatty acid membrane profile (increase in monounsaturated fatty acids, decrease in EPA and DHA-ω3 with a consequent increase in ω6/ω3 ratio) were found in Au compared to TD, without change in membrane sialic acid content. Some Au clinical features appear to be correlated with these findings; in particular, hyperactivity score appears to be related with some parameters of the lipidomic profile and membrane fluidity. Oxidative stress and erythrocyte membrane alterations may play a role in the pathogenesis of ASD and prompt the development of palliative therapeutic protocols. Moreover, the marked decrease in NKA could be potentially utilized as a peripheral biomarker of ASD.

Electroclinical presentation and genotype-phenotype relationships in patients with Unverricht-Lundborg disease carrying compound heterozygous CSTB point and indel mutations.

PURPOSE: Unverricht-Lundborg disease (EPM1A) is frequently due to an unstable expansion of a dodecamer repeat in the CSTB gene, whereas other types of mutations are rare. EPM1A due to homozygous expansion has a rather stereotyped presentation with prominent action myoclonus. We describe eight patients with five different compound heterozygous CSTB point or indel mutations in order to highlight their particular phenotypical presentations and evaluate their genotype-phenotype relationships. METHODS: We screened CSTB mutations by means of Southern blotting and the sequencing of the genomic DNA of each proband. CSTB messenger RNA (mRNA) aberrations were characterized by sequencing the complementary DNA (cDNA) of lymphoblastoid cells, and assessing the protein concentrations in the lymphoblasts. The patient evaluations included the use of a simplified myoclonus severity rating scale, multiple neurophysiologic tests, and electroencephalography (EEG)-polygraphic recordings. To highlight the particular clinical features and disease time-course in compound heterozygous patients, we compared some of their characteristics with those observed in a series of 40 patients carrying the common homozygous expansion mutation observed at the C. Besta Foundation, Milan, Italy. KEY FINDINGS: The eight compound heterozygous patients belong to six EPM1A families (out of 52; 11.5%) diagnosed at the Laboratory of Genetics of the Galliera Hospitals in Genoa, Italy. They segregated five different heterozygous point or indel mutations in association with the common dodecamer expansion. Four patients from three families had previously reported CSTB mutations (c.67-1G>C and c.168+1_18del); one had a novel nonsense mutation at the first exon (c.133C>T) leading to a premature stop codon predicting a short peptide; the other three patients from two families had a complex novel indel mutation involving the donor splice site of intron 2 (c.168+2_169+21delinsAA) and leading to an aberrant transcript with a partially retained intron. The protein dose (cystatin B/ß-actin) in our heterozygous patients was 0.24 ± 0.02, which is not different from that assessed in patients bearing the homozygous dodecamer expansion. The compound heterozygous patients had a significantly earlier disease onset (7.4 ± 1.7 years) than the homozygous patients, and their disease presentations included frequent myoclonic seizures and absences, often occurring in clusters throughout the course of the disease. The seizures were resistant to the pharmacologic treatments that usually lead to complete seizure control in homozygous patients. EEG-polygraphy allowed repeated seizures to be recorded. Action myoclonus progressively worsened and all of the heterozygous patients older than 30 years were in wheelchairs. Most of the patients showed moderate to severe cognitive impairment, and six had psychiatric symptoms. SIGNIFICANCE: EPM1A due to compound heterozygous CSTB mutations presents with variable but often markedly severe and particular phenotypes. Most of our patients presented with the electroclinical features of severe epilepsy, which is unexpected in homozygous patients, and showed frequent seizures resistant to pharmacologic treatment. The presence of variable phenotypes (even in siblings) suggests interactions with other genetic factors influencing the final disease presentation.

Long-term outcome of epilepsy in Kabuki syndrome.

UNLABELLED: PURPOSES AND METHODS: Kabuki syndrome (KS) is a rare dysmorphic disorder characterized by multiple congenital anomalies and mental retardation. Although epilepsy is one of the most common clinical complications associated with KS, few studies have evaluated its electroclinical aspects and long-term outcome. Therefore, we describe here a clinical series of 10 Caucasian KS patients who developed epilepsy in childhood. We followed all children for at least 5 years. RESULTS: All patients presented partial seizures and interictal EEGs revealed focal epileptic paroxysms with prevalent involvement of temporo-occipital areas. Seven children had no central nervous system abnormalities, but enlargement of lateral ventricles, corpus callosum hypoplasia, and adenohypophysis hypoplasia were revealed in three. Although antiepileptic drug (AED) treatment was effective in controlling seizures and normalizing EEG abnormalities in 8 patients, the other 2 cases were resistant to multiple AEDs. In one of these two patients, withdrawal of AED resulted in status epilepticus and death. CONCLUSIONS: Partial seizures and temporo-occipital abnormalities on interictal EEG are common features of KS patients who suffer from epilepsy. Prognosis of this epilepsy is favourable in the majority of cases with complete disappearance of seizures and EEG abnormalities.

Analysis of LGI1 promoter sequence, PDYN and GABBR1 polymorphisms in sporadic and familial lateral temporal lobe epilepsy.

Autosomal dominant lateral temporal epilepsy (ADTLE) is a genetically transmitted epileptic syndrome characterized by focal seizures with predominant auditory symptoms likely originating from the lateral region of the temporal lobe. Mutations in coding region or exon splice sites of the leucine-rich, glioma-inactivated 1 (LGI1) gene account for about 50% of ADLTE families. De novo LGI1 mutations of the same kind have also been found in about 2.5% of non-familial cases with idiopathic partial epilepsy with auditory features (IPEAF). In both conditions, mutations in the LGI1 promoter region have not been reported. We sequenced the minimal promoter region of LGI1 in the probands of 16 ADLTE families and in 104 sporadic IPEAF patients and no mutations clearly linked to the disease were found. However, two polymorphisms, -500G>A and -507G>A, with potential functional implications were identified and analysed in the cohort of sporadic IPEAF patients but their frequencies did not differ from those found in a control population of similar age, gender and geographic origin. We also analysed in our study population the GABA(B) receptor 1 c.1465G>A and the prodynorphin promoter 68-bp repeat polymorphisms, previously associated with temporal lobe epilepsy. None of these polymorphisms showed a significant association with IPEAF, whereas a tendency towards association with the prodynorphin low expression (L) alleles was found in the small group of ADLTE index cases, in agreement with previous studies suggesting that this polymorphism is a susceptibility factor in familial forms of temporal lobe epilepsy.

Brain MRI findings in severe myoclonic epilepsy in infancy and genotype-phenotype correlations.

INTRODUCTION: To determine the occurrence of neuroradiological abnormalities and to perform genotype-phenotype correlations in severe myoclonic epilepsy of infancy (SMEI, Dravet syndrome). PATIENTS AND METHODS: Alpha-subunit type A of voltage-gated sodium channel (SCN1A) mutational screening was performed by denaturing high-performance liquid chromatography (DHPLC) and multiplex ligation probe amplification (MLPA). MRI inclusion criteria were: last examination obtained after the age of 4 years on 1.5-T systems; hippocampal cuts acquired perpendicular to the long axis of the hippocampus; qualitative assessment was performed on T(1)-weighted, T(2)-weighted, proton density, and 1-3 mm thick coronal FLAIR images. RESULTS: We collected 58 SMEI patients in whom last MRI was performed at or later than 4 years of age. SCN1A mutations occurred in 35 (60%) cases. Thirteen (22.4%) out of 58 patients showed abnormal MRIs. Eight patients showed cortical brain atrophy of which 3 associated to ventricles abnormalities, 1 to cerebellar atrophy, 1 to white matter hyperintensity; 3 patients had ventricles enlargement only; 1 patient showed hippocampal sclerosis (HS); 1 had focal cortical dysplasia. Genotype-phenotype analysis indicated that abnormal MRIs occurred more frequently in patients without SCN1A mutations (9/23; 39.1%) compared to those carrying SCN1A mutations (4/35; 11.4%) (p=0.02). CONCLUSION: Different brain abnormalities may occur in SMEI. Only one case with HS was observed; thus, our study does not support the association between prolonged febrile seizures and HS in SMEI. Abnormal MRIs were significantly more frequent in patients without SCN1A mutations. Prospective MRI studies will assess the etiological role of the changes observed in these patients.

Coeliac disease, epilepsy and cerebral calcifications.

Coeliac disease, epilepsy and cerebral calcifications (CEC) syndrome is a rare clinical condition. One hundred and seventy-one patients have been reported in the literature. Patients are mostly from Italy, Spain, and Argentina, suggesting a geographically restricted condition. Epilepsy is more frequently characterized by occipital seizures. It may be benign or drug-resistant, sometime evolving into severe epileptic encephalopathy. Gluten free diet (GFD) efficacy seems to be inversely related to the duration of epilepsy and the young age of the patient. Patients with cerebral calcifications (CC) and coeliac disease (CD) without epilepsy are considered as having an incomplete form of CEC syndrome. Some patients with epilepsy and CC without CD are supposed to have a CEC syndrome with silent or latent CD. Whether CEC syndrome is a genetic condition, or whether epilepsy and/or CC are a consequence of an untreated CD is unknown yet. Since histopathological findings seem to be the expression of vascular calcified malformation, CEC syndrome may be considered a genetically determined entity, such as a type of Sturge-Weber-like phacomatosis. Moreover, CEC, as well as CD, is associated with HLA-DQ2 and HLA-DQ8 phenotype and genotype. The progressive growth and late occurrence of CC before beginning a GFD, the demonstration of anti-gliadin antibodies in the cerebro-spinal fluid and the association with HLA class II genes, suggest that an immune reaction originating from the jejunal mucosa, triggered by gliadin in gluten intolerance predisposed subjects (HLA phenotype) may be responsible for seizures and CC. Moreover, a long-lasting untreated CD folic acid deficiency may cause calcifications. Probably, CEC is considered a genetic, non-inherited, ethnically and geographically restricted syndrome associated with environmental factors.