Vertical Parasagittal Hemispherotomy in a Pediatric Case of Epilepsy Due to Rasmussen Encephalitis: 2-Dimensional Operative Video.

Hemispherotomy is an effective disconnection technique for the treatment of different forms of drug-resistant epilepsy due to encephalopathies with unilateral hemispheric involvement.1-8 We describe the case of a 6-year-old child affected by Rasmussen encephalitis who underwent right vertical parasagittal hemispherotomy.9 The goal of the procedure was to isolate the basal ganglia region by interrupting the interhemispheric and intrahemispheric white matter connectivity. The main surgical steps include the transcortical approach to the lateral ventricle, the posterior callosotomy, the fimbria-fornix incision, the laterothalamic vertical incision, the anterior callosotomy, the frontobasal disconnection, and the transcaudate lateral incision to the anterior temporal horn.7,10 At 10-month follow-up, the patient was seizure free with a stable left hemiparesis. The antiepileptic therapy was progressively interrupted. The video describes the main surgical steps, using both intraoperative videos and advanced three-dimensional modeling of neuroimaging pictures. Patient' parents consented to the procedure. The participants and any identifiable individuals consented to publication of his/her image. Approval from the ethics committee was acquired.

Distinct neurodevelopmental and epileptic phenotypes associated with gain- and loss-of-function GABRB2 variants.

BACKGROUND: Variants in GABRB2, encoding the ß2 subunit of the γ-aminobutyric acid type A (GABAA) receptor, can result in a diverse range of conditions, ranging from febrile seizures to severe developmental and epileptic encephalopathies. However, the mechanisms underlying the risk of developing milder vs more severe forms of disorder remain unclear. In this study, we conducted a comprehensive genotype-phenotype correlation analysis in a cohort of individuals with GABRB2 variants. METHODS: Genetic and electroclinical data of 42 individuals harbouring 26 different GABRB2 variants were collected and accompanied by electrophysiological analysis of the effects of the variants on receptor function. FINDINGS: Electrophysiological assessments of α1ß2γ2 receptors revealed that 25/26 variants caused dysfunction to core receptor properties such as GABA sensitivity. Of these, 17 resulted in gain-of-function (GOF) while eight yielded loss-of-function traits (LOF). Genotype-phenotype correlation analysis revealed that individuals harbouring GOF variants suffered from severe developmental delay/intellectual disability (DD/ID, 74%), movement disorders such as dystonia or dyskinesia (59%), microcephaly (50%) and high risk of early mortality (26%). Conversely, LOF variants were associated with milder disease manifestations. Individuals with these variants typically exhibited fever-triggered seizures (92%), milder degrees of DD/ID (85%), and maintained ambulatory function (85%). Notably, severe movement disorders or microcephaly were not reported in individuals with loss-of-function variants. INTERPRETATION: The data reveals that genetic variants in GABRB2 can lead to both gain and loss-of-function, and this divergence is correlated with distinct disease manifestations. Utilising this information, we constructed a diagnostic flowchart that aids in predicting the pathogenicity of recently identified variants by considering clinical phenotypes. FUNDING: This work was funded by the Australian National Health & Medical Research Council, the Novo Nordisk Foundation and The Lundbeck Foundation.

Practical considerations for the use of fenfluramine to manage patients with Dravet syndrome or Lennox-Gastaut syndrome in clinical practice.

Fenfluramine (FFA), an antiseizure medication (ASM) with serotonergic and sigma-1 receptor activity, is used to manage patients with developmental and epileptic encephalopathies (DEEs). It is approved in the US for treating seizures associated with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS) in patients ≥2 years old and as add-on therapy for seizures associated with DS and LGS in the EU, UK, and Japan in similarly aged patients. Consensus guidelines for treatment of DS have recommended FFA to be an early-line ASM, and it has also shown efficacy in managing seizures associated with LGS. DS and LGS are DEEs associated with a range of seizure types, developmental impairments, and multiple comorbidities. Here we provide case vignettes describing 4 patients (3 DS and 1 LGS) aged 4-29 years old in whom up to 14 ASMs had previously failed, to illustrate real-world practice issues encountered by neurologists. This review provides guidance on the use of FFA in the context of ASM polytherapy and drug-drug interactions (DDIs), behavioral issues, dose titration, and adverse events. Along with data from the clinical trial program, these case vignettes emphasize the low risk of DDIs, a generally well-tolerated safety profile, and other seizure and nonseizure benefits (eg, improved cognition and sleep) associated with the use of FFA in DS or LGS. PLAIN LANGUAGE SUMMARY: Fenfluramine is used to treat seizures in individuals with Dravet syndrome and Lennox-Gastaut syndrome, but there are a range of issues that clinicians may face when treating patients. This review highlights four patients from the authors' everyday clinical work and offers guidance and practical considerations by neurologists with expertise in managing these complex conditions related to drug interactions, dosing, and side effects associated with fenfluramine.

Surgical and radiosurgical treatment of hypothalamic hamartoma: The Italian experience between 2011 and 2021.

OBJECTIVE: To investigate the Italian experience on the surgical and radiosurgical treatment of drug-resistant epilepsy due to hypothalamic hamartoma (HH) in the period 2011-2021 in six Italian epilepsy surgery centers, and to compare safety and efficacy profiles of the different techniques. METHODS: We collected pseudo-anonymized patient's data with at least 12 months of follow-up. Surgical outcome was defined according to Engel classification of seizure outcome. Univariate analysis was performed to assess the risk of post-operative seizures, categorized in dichotomous variable as favorable and unfavorable; explanatory variables were considered. Mann-Whitney or Chi-squared test were used to assess the presence of an association between variables (p < 0.05). RESULTS: Full presurgical and postoperative data about 42 patients from 6 epilepsy surgery centers were gathered. Engel class I was reached in the 65.8% and 66.6% of patients with gelastic and non-gelastic seizures, respectively. Other than daily non-gelastic seizures were associated with seizure freedom (p = 0.01), and the radiological type presented a trend toward significance (p = 0.12). SIGNIFICANCE: Endoscopic disconnection and laser interstitial thermal therapy are effective in the treatment of HH-related epilepsy, with a tolerable safety profile. Both gelastic and non-gelastic seizures can be treated, also in patients with a long history of seizures. PLAIN LANGUAGE SUMMARY: This study collected data about 42 patients with HH-related epilepsies. Endoscopic disconnection and laser therapy are both effective and safe in the treatment of hypothalamic hamartoma-related epilepsies.

Trends, outcomes, and complications of surgery for lesional epilepsy in infants and toddlers: A multicenter study.

OBJECTIVE: To assess seizure and developmental outcomes, their predictors, and complications in 160 children who, between 1998 and 2022, underwent surgery for lesional epilepsy with curative intent before the age of 3 years. To compare trends in epilepsy surgery in this age group before and after the year 2014. METHODS: Retrospective multicenter study. Descriptive and univariate analyses, and multivariable models for all outcomes. RESULTS: These 160 patients (76 F; 47.5%) underwent 169 surgeries (age at surgery 20.4 ± 9.4 months). At the last follow-up (77 ± 57.4 months), 121 patients (75.6%) were in Engel class I, 106 (66.2%) of whom were in Engel class Ia. Antiseizure medications were stopped in 84 patients (52.5%). Complications requiring reoperations were observed in 16 patients (10%; 9.5% of surgeries) and unexpected permanent deficits in 12 (7.5%; 7.1% of surgeries). Postoperative cognitive functions remained unchanged in 56 patients (44.4%), improved in 51 (40.5%), and worsened in 19 (15.1%). Multivariable analyses showed that the probability of achieving Engel class Ia was lower when the duration of epilepsy was longer, patients underwent preoperative video-EEG, and unexpected postoperative permanent deficits occurred. Cognitive improvement after surgery was associated with lower preoperative seizure frequency, better preoperative developmental level, and a longer postoperative follow-up. FCDII and tumors were the histopathologies carrying a higher probability of achieving seizure freedom, while polymicrogyria was associated with a lower probability of cognitive improvement. The number of patients operated on after 2014 was higher than before (61.3% vs. 38.7%), with stable outcomes. SIGNIFICANCE: Epilepsy surgery is effective and safe in infants and toddlers, although the complication rate is higher than seen in older patients. Shorter duration of epilepsy, lower seizure frequency, no need for video-EEG, tumors, and some malformations of cortical development are robust predictors of seizure and cognitive outcome that may be exploited to increase earlier referral. PLAIN LANGUAGE SUMMARY: This study analyzed the results of epilepsy surgery in 160 children who had been operated on before the age of 3 years at four Italian centers between 1998 and 2022. At the last follow-up (77 ± 57.4 months), 121 patients (75.6%) were free from disabling seizures, of which 106 (66.2%) were completely seizure-free since surgery. Major surgical complications occurred in 28 patients (17.5%), which is higher than observed with epilepsy surgery in general, but similar to hemispheric/multilobar surgery. Postoperative cognitive function remained unchanged in 56 patients (44.4%), improved in 51 (40.5%), and worsened in 19 (15.1%). Epilepsy surgery is effective and safe in infants and toddlers.

Outpatient management of prolonged seizures and seizure clusters to prevent progression to a higher-level emergency: Consensus recommendations of an expert working group.

OBJECTIVE: The management of prolonged seizures (PS) and seizure clusters (SC) is impeded by the lack of international, evidence-based guidance. We aimed to develop expert recommendations regarding consensus definitions of PS, SC, and treatment goals to prevent progression to higher-level emergencies such as status epilepticus (SE). METHODS: An expert working group, comprising 12 epileptologists, neurologists, and pharmacologists from Europe and North America, used a modified Delphi consensus methodology to develop and anonymously vote on statements. Consensus was defined as ≥75% voting "Agree"/"Strongly agree." RESULTS: All group members strongly agreed that termination of an ongoing seizure in as short a time as possible is the primary goal of rapid and early seizure termination (REST) and that an ideal medication for REST would start to act within 2 min of administration to terminate ongoing seizure activity. Consensus was reached on the terminology defining PS (with proposed thresholds of 5 min for prolonged focal seizures and 2 min for prolonged absence seizures and the convulsive phase of bilateral tonic-clonic seizures) and SC (an abnormal increase in seizure frequency compared with the individual patient's usual seizure pattern). All group members strongly agreed or agreed that patients who have experienced a PS should be offered a REST medication, and all patients who have experienced a SC should be offered an acute cluster treatment (ACT). Further, when prescribing a REST medication or ACT, a seizure action plan should be agreed upon in consultation with the patient and caregiver. SIGNIFICANCE: The expert working group had a high level of agreement on the recommendations for defining and managing PS and SC. These recommendations will complement the existing guidance for the management of acute seizures, with the possibility of treating them earlier to potentially avoid progression to more severe seizures, including SE.

Exploring concurrent validity of the CLN2 Clinical Rating Scale: Comparison to PedsQL using cerliponase alfa clinical trial data.

BACKGROUND: The CLN2 Clinical Rating Scale evaluates disease progression in CLN2 disease, an ultra-rare, neurodegenerative disorder with late infantile onset. To validate the Clinical Rating Scale, a comparison with the Pediatric Quality of Life Inventory (PedsQL) was conducted utilising clinical trial data investigating cerliponase alfa use in CLN2 disease. METHODS: Linear regression and mixed effects models were used to investigate the relationship between the Clinical Rating Scale and PedsQL using open-label, single-arm, phase 1/2 (NCT01907087) and ongoing extension study (NCT02485899) data of 23 children with CLN2 disease treated with cerliponase alfa for ≥96 weeks. RESULTS: Correlations between the four Clinical Rating Scale domains were low. Linear mixed effects analyses showed significant correlation between PedsQL and Clinical Rating Scale (Total score or motor-language [ML] score adjusted p-values <0.05), driven by the relationship with the PedsQL Physical domain. A statistically significant relationship was identified between the Clinical Rating Scale motor domain and PedsQL (Total score: adjusted p-value = 0.048, parameter estimate [PE] = 8.10; Physical domain score: adjusted p-value = 0.012; PE = 13.79). CONCLUSIONS: Each domain of the Clinical Rating Scale provides unique information on disease state. Validity of the scale is supported by its relationship with the PedsQL. Among the four domains of the Clinical Rating Scale, motor has the highest correlation to PedsQL, suggesting motor function as a driver of patients' quality of life. The lack of association between the remaining domains of the Clinical Rating Scale and PedsQL suggests that additional disease-specific measures may be needed to fully capture the quality of life impact of CLN2 disease. TRIAL REGISTRATION: NCT01907087, NCT02485899.

Seizure and movement disorder in CACNA1E developmental and epileptic encephalopathy: Two sides of the same coin or same side of two different coins?

Pathogenic variants in CACNA1E are associated with early-onset epileptic and developmental encephalopathy (DEE). Severe to profound global developmental delay, early-onset refractory seizures, severe hypotonia, and macrocephaly are the main clinical features. Patients harboring the recurrent CACNA1E variant p.(Gly352Arg) typically present with the combination of early-onset DEE, dystonia/dyskinesia, and contractures. We describe a 2-year-and-11-month-old girl carrying the p.(Gly352Arg) CACNA1E variant. She has a severe DEE with very frequent drug-resistant seizures, profound hypotonia, and episodes of dystonia and dyskinesia. Long-term video-EEG-monitoring documented subsequent tonic asymmetric seizures during wakefulness and mild paroxysmal dyskinesias of the trunk out of sleep which were thought to be a movement disorder and instead turned out to be focal hyperkinetic seizures. This is the first documented description of the EEG findings in this disorder. Our report highlights a possible overlap between cortical and subcortical phenomena in CACNA1E-DEE. We also underline how a careful electro-clinical evaluation might be necessary for a correct discernment between the two disorders, playing a fundamental role in the clinical assessment and proper management of children with CACNA1E-DEE.

Post-Traumatic Stress-Disorder in Epilepsy: Meta-analysis of current evidence.

Epilepsy, a chronic neurological condition characterized by unpredictable seizures, poses considerable challenges, including disability, stigma, and increased mortality. Psychiatric comorbidities are prevalent in 20-30% of epilepsy patients, notably mood or anxiety disorders, psychotic symptoms, and personality disorders. Trauma and childhood adversities are pivotal risk factors for psychopathology, yet the link between Post-Traumatic Stress Disorder (PTSD) and epilepsy remains underexplored. This meta-analysis is aimed to establish updated estimates of PTSD prevalence among individuals with epilepsy. Fifteen studies, comprising 996 epilepsy patients, were included. The overall pooled prevalence of PTSD in epilepsy patients was 18%. Notably, patients with epilepsy exhibited a three-fold increased risk of developing PTSD compared to the general population. Subgroup analysis revealed a higher PTSD prevalence in uncontrolled studies (25%) compared to controlled studies (14%). Additionally, patients with Psychogenic Non-Epileptic Seizures (PNES) demonstrated higher PTSD prevalence than epilepsy patients, with a threefold higher risk in healthy controls compared to PNES controls. While gender prevalence did not significantly affect PTSD occurrence, drug resistant epilepsy did not correlate with PTSD prevalence. Moreover, age of epilepsy onset showed no significant correlation with PTSD prevalence. This meta-analysis underscores the substantial burden of PTSD among epilepsy patients, potentially attributable to the traumatic nature of seizures and the chronic stigma associated with epilepsy. Improved recognition and management of psychiatric conditions, particularly PTSD, are crucial in epilepsy care pathways to enhance patients' quality of life. Further research and comprehensive diagnostic tools are imperative to better understand and address the prevalence of PTSD in epilepsy patients.

Hypothalamic Hamartoma related epilepsy: A systematic review exploring clinical, neuropsychological, and psychiatric outcome after surgery.

The post-surgical outcome for Hypothalamic Hamartoma (HH) related epilepsy in terms of seizure freedom (SF) has been extensively studied, while cognitive and psychiatric outcome has been less frequently reported and defined. This is a systematic review of English language papers, analyzing the post-surgical outcome in series of patients with HH-related epilepsy (≥5 patients, at least 6 months follow-up), published within January 2002-December 2022. SF was measured using Engel scale/equivalent scales. We looked at the outcome related to different surgical techniques, and HH types according to Delalande classification. We evaluated the neuropsychological and neuropsychiatric status after surgery, and the occurrence of post-surgical complications. Forty-six articles reporting 1318 patients were included, of which ten pediatric series. SF was reported in 686/1222 patients (56,1%). Delalande classification was reported in 663 patients from 24 studies, of which 70 were type I HH (10%), 320 were type II HH (48%), 189 were type III HH (29%) and 84 were type IV HH (13%). The outcome in term of SF was reported in 243 out of 663 patients. SF was reported in 12 of 24 type I HH (50%), 80 of 132 type II HH (60,6%), 32 of 59 type III HH (54,2%) and 12 of 28 type IV HH (42,9%). SF was reached in 129/262 (49,2%) after microsurgery, 102/199 (51,3%) after endoscopic surgery, 46/114 (40,6%) after gamma knife surgery, 245/353 (69,4%) after radiofrequency thermocoagulation, and 107/152 (70,4%) after MRI-guided laser interstitial thermal therapy. Hyperphagia/weight gain were the most reported surgical complications. Others were electrolyte alterations, diabetes insipidus, hypotiroidism, transient hyperthermia/poikilothermia. The highest percentage of memory deficits was reported after microsurgery, while hemiparesis and cranial nerves palsy were reported after microsurgery or endoscopic surgery. Thirty studies reported developmental delay/intellectual disability in 424/819 (51,7%) patients. 248/346 patients obtained a global improvement (72%), 70/346 were stable (20%), 28/346 got worse (8%). 22 studies reported psychiatric disorders in 257/465 patients (55,3%). 78/98 patients improved (80%), 13/98 remained stable (13%), 7/98 got worse (7%). Most of the patients had non-structured cognitive/psychiatric assessments. Based on the available data, the surgical management in patients with HH related epilepsy should be individualized, aiming to reach not only the best epilepsy result, but also the optimal cognitive and psychiatric outcome.

The value of linear and non-linear quantitative EEG analysis in paediatric epilepsy surgery: a machine learning approach.

Epilepsy surgery is effective for patients with medication-resistant seizures, however 20-40% of them are not seizure free after surgery. Aim of this study is to evaluate the role of linear and non-linear EEG features to predict post-surgical outcome. We included 123 paediatric patients who underwent epilepsy surgery at Bambino Gesù Children Hospital (January 2009-April 2020). All patients had long term video-EEG monitoring. We analysed 1-min scalp interictal EEG (wakefulness and sleep) and extracted 13 linear and non-linear EEG features (power spectral density (PSD), Hjorth, approximate entropy, permutation entropy, Lyapunov and Hurst value). We used a logistic regression (LR) as feature selection process. To quantify the correlation between EEG features and surgical outcome we used an artificial neural network (ANN) model with 18 architectures. LR revealed a significant correlation between PSD of alpha band (sleep), Mobility index (sleep) and the Hurst value (sleep and awake) with outcome. The fifty-four ANN models gave a range of accuracy (46-65%) in predicting outcome. Within the fifty-four ANN models, we found a higher accuracy (64.8% ± 7.6%) in seizure outcome prediction, using features selected by LR. The combination of PSD of alpha band, mobility and the Hurst value positively correlate with good surgical outcome.

Providing quality care for people with CDKL5 deficiency disorder: A European expert panel opinion on the patient journey.

Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a developmental and epileptic encephalopathy caused by variants in the CDKL5 gene. The disorder is characterized by intractable early-onset seizures, severe neurodevelopmental delay, hypotonia, motor disabilities, cerebral (cortical) visual impairment and microcephaly. With no disease-modifying therapies available for CDD, treatment is symptomatic with an initial focus on seizure control. Another unmet need in the management of people with CDD is the lack of evidence to aid standardized care and guideline development. To address this gap, experts in CDD and representatives from patient advocacy groups from Denmark, Finland, France, Germany, Italy, Poland, Spain, and the United Kingdom convened to form an Expert Working Group. The aim was to provide an expert opinion consensus on how to ensure quality care in routine clinical practice within the European setting, including in settings with limited experience or resources for multidisciplinary care of CDD and other developmental and epileptic encephalopathies. By means of one-to-one interviews around the current treatment landscape in CDD, insights from the Expert Working Group were collated and developed into a Europe-specific patient journey for individuals with CDD, which was later validated by the group. Further discussions followed to gain consensus of opinions on challenges and potential solutions for achieving quality care in this setting. The panel recognized the benefit of early genetic testing, a holistic personalized approach to seizure control (taking into consideration various factors such as concomitant medications and comorbidities), and age- and comorbidity-dependent multidisciplinary care for optimizing patient outcomes and quality of life. However, their insights and experiences also highlighted much disparity in management approaches and resources across different European countries. Development of standardized European recommendations is required to align realistic diagnostic criteria, treatment goals, and management approaches that can be adapted for different settings. PLAIN LANGUAGE SUMMARY: Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a rare condition caused by a genetic mutation with a broad range of symptoms apparent from early childhood, including epileptic seizures that do not respond to medication and severe delays in development. Due to the lack of guidance on managing CDD, international experts and patient advocates discussed best practices in the care of people with CDD in Europe. The panel agreed that early testing, a personalized approach to managing seizures, and access to care from different disciplines are beneficial. Development of guidelines to ensure that care is standardized would also be valuable.

Accessibility, availability and common practices regarding genetic testing for epilepsy across Europe: A survey of the European Reference Network EpiCARE.

OBJECTIVE: The increasingly rapid pace of advancement in genetic testing may lead to inequalities in technical and human resources with a negative impact on optimal epilepsy clinical practice. In this view, the European Reference Network (ERN) for Rare and Complex Epilepsies EpiCARE conducted a survey addressing several aspects of accessibility, availability, costs, and standard practices on genetic testing across ERN EpiCARE centers. METHODS: An online Google form was sent to 70 representatives of ERN EpiCARE centers. Descriptive statistics and qualitative analysis were used for data presentation. RESULTS: We received 45 responses (1/center) representing 23 European countries with a better representation of Western Europe. Forty-five percent of the centers did not have access to all available types of genetic testing, mainly reflecting the limited availability of whole-genome sequencing (WGS). Thirty-five percent of centers report cost coverage only for some of the available tests, while costs per test varied significantly (interquartile range IQR ranging from 150 to 1173 euros per test across centers). Urgent genetic testing is available in 71.7% of countries (time-to-urgent result: 2 day to 2 months). The average time-to-result of specific tests in case of non-urgent prescription has a significant variance across centers, with the biggest range observed for whole-exome sequencing (6-128 weeks, IQR: 27 weeks). The percentage of agreement among the experts regarding the choice of genetic test at first intention in specific clinical situations was in all cases less than 50 percent (34.9% to 47% according to the proposed scenarios). SIGNIFICANCE: Costs, time to deliver the results to the clinician, and type of first-line genetic testing vary widely across Europe, even in countries where ERN EpiCARE centers are present. Increased availability of genetic tests and guidance for optimal test choices in epilepsy remains essential to avoid diagnostic delays and excess health costs. PLAIN LANGUAGE SUMMARY: The survey of the ERN EpiCARE highlights disparities in genetic testing for epilepsy across 45 ERN EpiCARE centers in 23 European countries. The findings reveal variable access to certain genetic tests, with lowest access to WGS. Costs and time-to-results vary widely. Urgent genetic testing is available in 71.7% of countries. Agreement among experts on first-line genetic tests for specific patient scenarios is below 50%. The study emphasizes the need for improved test availability and guidance to avoid diagnostic delays and unnecessary costs. EpiCARE has the mission to contribute in homogenizing best practices across Europe.

Morphometric network-based abnormalities correlate with psychiatric comorbidities and gene expression in PCDH19-related developmental and epileptic encephalopathy.

Protocadherin-19 (PCDH19) developmental and epileptic encephalopathy causes an early-onset epilepsy syndrome with limbic seizures, typically occurring in clusters and variably associated with intellectual disability and a range of psychiatric disorders including hyperactive, obsessive-compulsive and autistic features. Previous quantitative neuroimaging studies revealed abnormal cortical areas in the limbic formation (parahippocampal and fusiform gyri) and underlying white-matter fibers. In this study, we adopted morphometric, network-based and multivariate statistical methods to examine the cortex and substructure of the hippocampus and amygdala in a cohort of 20 PCDH19-mutated patients and evaluated the relation between structural patterns and clinical variables at individual level. We also correlated morphometric alterations with known patterns of PCDH19 expression levels. We found patients to exhibit high-significant reductions of cortical surface area at a whole-brain level (left/right pvalue = 0.045/0.084), and particularly in the regions of the limbic network (left/right parahippocampal gyri pvalue = 0.230/0.016; left/right entorhinal gyri pvalue = 0.002/0.327), and bilateral atrophy of several subunits of the amygdala and hippocampus, particularly in the CA regions (head of the left CA3 pvalue = 0.002; body of the right CA3 pvalue = 0.004), and differences in the shape of hippocampal structures. More severe psychiatric comorbidities correlated with more significant altered patterns, with the entorhinal gyrus (pvalue = 0.013) and body of hippocampus (pvalue = 0.048) being more severely affected. Morphometric alterations correlated significantly with the known expression patterns of PCDH19 (rvalue = -0.26, pspin = 0.092). PCDH19 encephalopathy represents a model of genetically determined neural network based neuropsychiatric disease in which quantitative MRI-based findings correlate with the severity of clinical manifestations and had have a potential predictive value if analyzed early.

Fenfluramine below the age of 2 years in Dravet syndrome: What about safety and efficacy?

Dravet syndrome (DS) is a rare developmental and epileptic encephalopathy. Infants with DS are especially vulnerable to the detrimental effects of prolonged and frequent seizures on development. Fenfluramine (FFA) is approved for the treatment of DS in patients aged 2 years and older. This study aims to evaluate the safety and efficacy of FFA in patients with DS younger than 2 years. We analyzed safety, tolerability, seizure, and neuropsychological outcome in a real-world setting. Developmental profile was investigated using Griffiths Mental Development Scales (GMDS). Five patients received FFA at a mean age of 14.9 months (9.6-18.6). Median follow-up was 13 months (interquartile range [IQR] = 12.9-24.4). All patients showed good tolerance to FFA. No significant variation of body mass index or echocardiographic issue was observed. Monthly median convulsive seizure frequency (MCSF) was 1.71 (IQR = 1.56-3.27) at the 6-month baseline period and .92 (IQR = .43-1.28) at last follow-up, with a median 54.43 (IQR = 40.91-60.83) percentage reduction in MCSF. Two of five patients had a performance improvement on GMDS subscales. Overall, the use of FFA below the age of 2 years in our small sample of patients was safe and represents a promising opportunity for seizure control and for protection of the neurodevelopmental outcome.

Is tuberous sclerosis complex-associated autism a preventable and treatable disorder?

BACKGROUND: Tuberous sclerosis complex (TSC) is a genetic disorder caused by inactivating mutations in the TSC1 and TSC2 genes, causing overactivation of the mechanistic (previously referred to as mammalian) target of rapamycin (mTOR) signaling pathway in fetal life. The mTOR pathway plays a crucial role in several brain processes leading to TSC-related epilepsy, intellectual disability, and autism spectrum disorder (ASD). Pre-natal or early post-natal diagnosis of TSC is now possible in a growing number of pre-symptomatic infants. DATA SOURCES: We searched PubMed for peer-reviewed publications published between January 2010 and April 2023 with the terms "tuberous sclerosis", "autism", or "autism spectrum disorder"," animal models", "preclinical studies", "neurobiology", and "treatment". RESULTS: Prospective studies have highlighted that developmental trajectories in TSC infants who were later diagnosed with ASD already show motor, visual and social communication skills in the first year of life delays. Reliable genetic, cellular, electroencephalography and magnetic resonance imaging biomarkers can identify pre-symptomatic TSC infants at high risk for having autism and epilepsy. CONCLUSIONS: Preventing epilepsy or improving therapy for seizures associated with prompt and tailored treatment strategies for autism in a sensitive developmental time window could have the potential to mitigate autistic symptoms in infants with TSC.

Safety and efficacy of cerliponase alfa in children with neuronal ceroid lipofuscinosis type 2 (CLN2 disease): an open-label extension study.

BACKGROUND: Cerliponase alfa is a recombinant human tripeptidyl peptidase 1 (TPP1) enzyme replacement therapy for the treatment of neuronal ceroid lipofuscinosis type 2 (CLN2 disease), which is caused by mutations in the TPP1 gene. We aimed to determine the long-term safety and efficacy of intracerebroventricular cerliponase alfa in children with CLN2 disease. METHODS: This analysis includes cumulative data from a primary 48-week, single-arm, open-label, multicentre, dose-escalation study (NCT01907087) and the 240-week open-label extension with 6-month safety follow-up, conducted at five hospitals in Germany, Italy, the UK, and the USA. Children aged 3-16 years with CLN2 disease confirmed by genetic analysis and enzyme testing were eligible for inclusion. Treatment was intracerebroventricular infusion of 300 mg cerliponase alfa every 2 weeks. Historical controls with untreated CLN2 disease in the DEM-CHILD database were used as a comparator group. The primary efficacy outcome was time to an unreversed 2-point decline or score of 0 in the combined motor and language domains of the CLN2 Clinical Rating Scale. This extension study is registered with ClinicalTrials.gov, NCT02485899, and is complete. FINDINGS: Between Sept 13, 2013, and Dec 22, 2014, 24 participants were enrolled in the primary study (15 female and 9 male). Of those, 23 participants were enrolled in the extension study, conducted between Feb 2, 2015, and Dec 10, 2020, and received 300 mg cerliponase alfa for a mean of 272·1 (range 162·1-300·1) weeks. 17 participants completed the extension and six discontinued prematurely. Treated patients were significantly less likely than historical untreated controls to have an unreversed 2-point decline or score of 0 in the combined motor and language domains (hazard ratio 0·14, 95% CI 0·06 to 0·33; p<0·0001). All participants experienced at least one adverse event and 21 (88%) experienced a serious adverse event; nine participants experienced intracerebroventricular device-related infections, with nine events in six participants resulting in device replacement. There were no study discontinuations because of an adverse event and no deaths. INTERPRETATION: Cerliponase alfa over a mean treatment period of more than 5 years was seen to confer a clinically meaningful slowing of decline of motor and language function in children with CLN2 disease. Although our study does not have a contemporaneous control group, the results provide crucial insights into the effects of long-term treatment. FUNDING: BioMarin Pharmaceutical.

Updated Genotype-Phenotype Correlations in TSC.

GENOTYPE/PHENOTYPE CORRELATIONS IN TUBEROUS SCLEROSIS COMPLEX: Paolo Curatolo MD, Romina Moavero MD, Denis Roberto, Federica Graziola Seminars in Pediatric Neurology Volume 22, Issue 4, December 2015, Pages 259-273 Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by the development of widespread hamartomatous lesions in various organs, including brain, skin, kidneys, heart, and eyes. Central nervous system is almost invariably involved, with up to 85% of patients presenting with epilepsy, and at least half of patients having intellectual disability or other neuropsychiatric disorders including autism spectrum disorder. TSC is caused by the mutation in one of the 2 genes TSC1, at 9q34, and TSC2, at 16p13.3. They respectively encode for hamartin and tuberin, which form an intracellular complex inhibiting the mammalian target of rapamycin. Mammalian target of rapamycin overactivation following the genetic defect determines the cell growth and proliferation responsible for TSC-related lesions, as well as the alterations in neuronal excitability and synaptogenesis leading to epilepsy and neuropsychiatric disorders. A causative mutation for the disorder is identified in about 85% of patients with a clinical diagnosis of TSC. Mosaicism and technology limits likely explain most of the no mutation identified cases. This review confirms that patients with TSC2 mutations considered as a group usually present a more severe phenotype, characterized by higher number of tubers, earlier age at seizure onset and higher prevalence of intellectual disability. However, the clinical phenotype of the disease presents a high variability, thus making the prediction of the phenotype on an individual basis still challenging. The increasing application of new molecular techniques to subjects with TSC has the potential to significantly reduce the rate of patients with no mutation demonstrated and to identify an increasing higher number of mutations. This would hopefully allow a better characterization of higher risk mutations, which might help clinicians to plan individualized surveillance plans. Furthermore, the increasing availability of disease registries to collect clinical and genetics data of patients help to define more valid and clinically oriented genotype or phenotype correlations.

Updated clinical recommendations for the management of tuberous sclerosis complex associated epilepsy.

Children with tuberous sclerosis complex (TSC), may experience a variety of seizure types in the first year of life, most often focal seizure sand epileptic spasms. Drug resistance is seen early in many patients, and the management of TSC associated epilepsy remain a major challenge for clinicians. In 2018 clinical recommendations for the management of TSC associated epilepsy were published by a panel of European experts. In the last five years considerable progress has been made in understanding the neurobiology of epileptogenesis and three interventional randomized controlled trials have changed the therapeutic approach for the management of TSC associated epilepsy. Pre-symptomatic treatment with vigabatrin may delay seizure onset, may reduce seizure severity and reduce the risk of epileptic encephalopathy. The efficacy of mTOR inhibition with adjunctive everolimus was documented in patients with TSC associated refractory seizures and cannabidiol could be another therapeutic option. Epilepsy surgery has significantly improved seizure outcome in selected patients and should be considered early in all patients with drug resistant epilepsy. There is a need to identify patients who may have a higher risk of developing epilepsy and autism spectrum disorder (ASD). In the recent years significant progress has been made owing to the early identification of risk factors for the development of drug-resistant epilepsy. Better understanding of the mechanism underlying epileptogenesis may improve the management for TSC-related epilepsy. Developmental neurobiology and neuropathology give opportunities for the implementation of concepts related to clinical findings, and an early genetic diagnosis and use of EEG and MRI biomarkers may improve the development of pre-symptomatic and disease-modifying strategies.