Polymicrogyria: epidemiology, imaging, and clinical aspects in a population-based cohort.

Polymicrogyria is estimated to be one of the most common brain malformations, accounting for ∼16% of malformations of cortical development. However, the prevalence and incidence of polymicrogyria is unknown. Our aim was to estimate the prevalence, incidence rate, neuroimaging diversity, aetiology, and clinical phenotype of polymicrogyria in a population-based paediatric cohort. We performed a systematic search of MRI scans at neuroradiology department databases in Stockholm using the keyword polymicrogyria. The study population included all children living in the Stockholm region born from January 2004 to June 2021 with polymicrogyria. Information on the number of children living in the region during 2004-21 was collected from records from Statistics Sweden, whereas the number of births for each year during the study period was collected from the Swedish Medical Birth Register. All MRI scans were re-evaluated, and malformations were classified by a senior paediatric neuroradiologist. The prevalence and yearly incidence were estimated. Clinical data were collected from medical records. A total of 109 patients with polymicrogyria were included in the study. The overall polymicrogyria prevalence in Stockholm was 2.3 per 10 000 children, and the overall estimated yearly incidence between 2004 and 2020 was 1.9 per 10 000 person-years. The most common polymicrogyria distribution was in the frontal lobe (71%), followed by the parietal lobe (37%). Polymicrogyria in the peri-sylvian region was observed in 53%. Genetic testing was performed in 90 patients revealing pathogenic variants in 32%. Additionally, 12% had variants of uncertain significance. Five patients had a confirmed congenital infection, and in six individuals, the cause of polymicrogyria was assumed to be vascular. Epilepsy was diagnosed in 54%. Seizure onset during the first year of life was observed in 44%. The most common seizure types were focal seizures with impaired awareness, followed by epileptic spasms. Thirty-three of 59 patients with epilepsy (56%) were treated with more than two anti-seizure medications, indicating that pharmacoresistant epilepsy is common in polymicrogyria patients. Neurodevelopmental symptoms were observed in 94% of the individuals. This is the first population-based study on polymicrogyria prevalence and incidence. Confirmed genetic aetiology was present in one-third of individuals with polymicrogyria. Epilepsy was common in this patient group, and the majority had pharmacoresistant epilepsy. These findings increase our knowledge about polymicrogyria and will help in counselling patients and their families.

Higher levels of Bifidobacteria and tumor necrosis factor in children with drug-resistant epilepsy are associated with anti-seizure response to the ketogenic diet.

BACKGROUND: Recently, studies have suggested a role for the gut microbiota in epilepsy. Gut microbial changes during ketogenic diet (KD) treatment of drug-resistant epilepsy have been described. Inflammation is associated with certain types of epilepsy and specific inflammation markers decrease during KD. The gut microbiota plays an important role in the regulation of the immune system and inflammation. METHODS: 28 children with drug-resistant epilepsy treated with the ketogenic diet were followed in this observational study. Fecal and serum samples were collected at baseline and three months after dietary intervention. FINDINGS: We identified both gut microbial and inflammatory changes during treatment. KD had a general anti-inflammatory effect. Novel bioinformatics and machine learning approaches identified signatures of specific Bifidobacteria and TNF (tumor necrosis factor) associated with responders before starting KD. During KD, taxonomic and inflammatory profiles between responders and non-responders were more similar than at baseline. INTERPRETATION: Our results suggest that children with drug-resistant epilepsy are more likely to benefit from KD treatment when specific Bifidobacteria and TNF are elevated. We here present a novel signature of interaction of the gut microbiota and the immune system associated with anti-epileptic response to KD treatment. This signature could be used as a prognostic biomarker to identify potential responders to KD before starting treatment. Our findings may also contribute to the development of new anti-seizure therapies by targeting specific components of the gut microbiota. FUNDING: This study was supported by the Swedish Brain Foundation, Margarethahemmet Society, Stiftelsen Sunnerdahls Handikappfond, Linnea & Josef Carlssons Foundation, and The McCormick Genomic & Proteomic Center.

Novel imaging findings in pyruvate dehydrogenase complex (PDHc) deficiency-Results from a nationwide population-based study.

The vast clinical and radiological spectrum of pyruvate dehydrogenase complex (PDHc) deficiency continues to pose challenges both in diagnostics and disease monitoring. Prompt diagnosis is important to enable early initiation of ketogenic diet. The patients were recruited from an ongoing population-based study in Sweden. All patients with a genetically confirmed diagnosis who had been investigated with an MRI of the brain were included. Repeated investigations were assessed to study the evolution of the MRI changes. Sixty-two MRI investigations had been performed in 34 patients (23 females). The genetic cause was mutations in PDHA1 in 29, PDHX and DLAT in 2 each, and PDHB in 1. The lesions were prenatal developmental in 16, prenatal clastic in 18, and postnatal clastic in 15 individuals. Leigh-like lesions with predominant involvement of globus pallidus were present in 12, while leukoencephalopathy was present in 6 and stroke-like lesions in 3 individuals. A combination of prenatal developmental and clastic lesions was present in 15 individuals. In addition, one male with PDHA1 also had postnatal clastic lesions. The most common lesions found in our study were agenesis or hypoplasia of corpus callosum, ventriculomegaly, or Leigh-like lesions. Furthermore, we describe a broad spectrum of other MRI changes that include leukoencephalopathy and stroke-like lesions. We argue that a novel important clue, suggesting the possibility of PDHc deficiency on MRI scans, is the simultaneous presence of multiple lesions on MRI that have occurred during different phases of brain development.

Resolving the biological paradox of aneurysm formation in children with tuberous sclerosis complex.

Aortic aneurysms are rare manifestations in children with tuberous sclerosis complex (TSC) with life threating implications. Although an association between TSC, aortic and other aneurysms has been recognized, mechanistic insights explaining the pathophysiology behind aneurysm development and genetic aberrations in TSC have so far been lacking. Here, we summarize existing knowledge on aneurysms in TSC and present a case of a 2-year-old boy with an infrarenal aortic aneurysm, successfully treated with open aortic reconstruction. Histologic examination of the excised aneurysm wall showed distortion of vessel wall structure with loss of elastin and a pathologic accumulation of smooth muscle cells. Until now, these pathologic features have puzzled researchers as proliferating smooth muscle cells would rather be expected to preserve vessel wall integrity. Recent reports exploring the biological consequences of the dysregulated intracellular signaling pathways in patients with TSC provide plausible explanations to this paradox, which may support the development of future therapeutic strategies.

Altered cytokine levels in cerebrospinal fluid following ketogenic diet of children with refractory epilepsy.

Ketogenic diet is an effective treatment which has the potential to achieve a significant seizure reduction in drug-resistant epilepsy. The mechanism behind this effect is unclear, but one hypothesis is that the mechanism is anti-inflammatory. In this prospective study on pediatric patients we compared levels of cytokines and chemokines in the cerebrospinal fluid before and after three months on treatment to evaluate a possible anti-inflammatory effect. We analyzed 34 cytokines and chemokines in the cerebrospinal fluid of pediatric patients (n = 21) with refractory epilepsy by a multiplex assay. Beta-hydroxybutyric acid was measured in blood and cerebrospinal fluid. Seizure frequency in relation to diet treatment was assessed. For 9 different cytokines (CCL 7, CCL 21, CCL 22, CCL 25, CCL 27, IL-2, IL-10, CX3CL1 and MIF), a significant decrease ranging from 7 to 27% was seen after three months as compared to levels before the diet. In contrast, no cytokine displayed a significant increase during diet. A seizure reduction ≥ 50 % was seen in 15/21 patients (71 %) but no significant differences in cytokine decreases were found between responders and non-responders during treatment. A non-significant trend towards higher initial pre-treatment levels of cytokines was seen in responders, which were reduced following treatment. The levels of betahydroxybutyric acid were not related to seizure response. We conclude that while it is not possible to state a primary anti-inflammatory effect by dietary treatment from these data, an unequivocal immunological effect is seen and may be a part of the mechanism of ketogenic dietary treatment.

Historical Patterns of Diagnosis, Treatments, and Outcome of Epilepsy Associated With Tuberous Sclerosis Complex: Results From TOSCA Registry.

Background: Epilepsy is the most common neurological manifestation in individuals with tuberous sclerosis complex (TSC). However, real-world evidence on diagnosis and treatment patterns is limited. Here, we present data from TuberOus Sclerosis registry to increase disease Awareness (TOSCA) on changes in patterns of epilepsy diagnosis, treatments, and outcomes over time, and detailed epilepsy characteristics from the epilepsy substudy. Methods: TuberOus Sclerosis registry to increase disease Awareness (TOSCA) was a multicentre, international disease registry, consisting of a main study that collected data on overall diagnostic characteristics and associated clinical features, and six substudies focusing on specific TSC manifestations. The epilepsy substudy investigated detailed epilepsy characteristics and their correlation to genotype and intelligence quotient (IQ). Results: Epilepsy was reported in 85% of participants, more commonly in younger individuals (67.8% in 1970s to 91.8% in last decade), while rate of treatments was similar across ages (>93% for both infantile spasms and focal seizures, except prior to 1960). Vigabatrin (VGB) was the most commonly used antiepileptic drugs (AEDs). Individuals with infantile spasms showed a higher treatment response over time with lower usage of steroids. Individuals with focal seizures reported similar rates of drug resistance (32.5-43.3%). Use of vagus nerve stimulation (VNS), ketogenic diet, and surgery remained low. Discussion: The epilepsy substudy included 162 individuals from nine countries. At epilepsy onset, most individuals with infantile spasms (73.2%) and focal seizures (74.5%) received monotherapies. Vigabatrin was first-line treatment in 45% of individuals with infantile spasms. Changes in initial AEDs were commonly reported due to inadequate efficacy. TSC1 mutations were associated with less severe epilepsy phenotypes and more individuals with normal IQ. In individuals with TSC diagnosis before seizure onset, electroencephalogram (EEG) was performed prior to seizures in only 12.5 and 25% of subsequent infantile spasms and focal seizures, respectively. Conclusions: Our study confirms the high prevalence of epilepsy in TSC individuals and less severe phenotypes with TSC1 mutations. Vigabatrin improved the outcome of infantile spasms and should be used as first-line treatment. There is, however, still a need for improving therapies in focal seizures. Electroencephalogram follow-up prior to seizure-onset should be promoted for all infants with TSC in order to facilitate preventive or early treatment.

Rare manifestations and malignancies in tuberous sclerosis complex: findings from the TuberOus SClerosis registry to increAse disease awareness (TOSCA).

BACKGROUND: Tuberous sclerosis complex (TSC) is a rare multisystem autosomal dominant disorder caused by pathogenic variants in either the TSC1 or TSC2 gene. Common manifestations of TSC have been grouped into major and minor clinical diagnostic criteria and assessed in clinical routine workup. However, case studies point towards the existence of rare disease manifestations and to the potential association of TSC with malignant tumors. In this study we sought to characterize rare manifestations and malignancies using a large cohort of patients. METHODS: TuberOus SClerosis registry to increAse disease awareness (TOSCA) is a multicenter, international disease registry collecting clinical manifestations and characteristics of patients with TSC, both retrospectively and prospectively. We report rates and characteristics of rare manifestations and malignancies in patients with TSC who had enrolled in the TOSCA registry. We also examined these manifestations by age, sex, and genotype (TSC1 or TSC2). RESULTS: Overall, 2211 patients with TSC were enrolled in the study. Rare manifestations were reported in 382 (17.3%) study participants and malignancies in 65 (2.9%). Of these rare manifestations, the most frequent were bone sclerotic foci (39.5%), scoliosis (23%), thyroid adenoma (5.5%), adrenal angiomyolipoma (4.5%), hemihypertrophy and pancreatic neuroendocrine tumors (pNET; both 3.1%). These rare manifestations were more commonly observed in adults than children (66.2% vs. 22.7%), in females versus males (58.4% vs. 41.6%; except for scoliosis: 48.9% vs. 51.1%), and in those with TSC2 versus TSC1 (67.0% vs. 21.1%; except for thyroid adenoma: 42.9% vs. 57.1%). In the 65 individuals with reported malignancies, the most common were renal cell carcinoma (47.7%), followed by breast (10.8%) and thyroid cancer (9.2%). Although malignancies were more common in adult patients, 26.1% were reported in children and 63.1% in individuals < 40 years. TSC1 mutations were over-represented in individuals with malignancies compared to the overall TOSCA cohort (32.1% vs. 18.5%). CONCLUSION: Rare manifestations were observed in a significant proportion of individuals with TSC. We recommend further examination of rare manifestations in TSC. Collectively, malignancies were infrequent findings in our cohort. However, compared to the general population, malignant tumors occurred earlier in age and some tumor types were more common.

TuberOus SClerosis registry to increAse disease awareness (TOSCA) Post-Authorisation Safety Study of Everolimus in Patients With Tuberous Sclerosis Complex.

This non-interventional post-authorisation safety study (PASS) assessed the long-term safety of everolimus in patients with tuberous sclerosis complex (TSC) who participated in the TuberOus SClerosis registry to increase disease Awareness (TOSCA) clinical study and received everolimus for the licensed indications in the European Union. The rate of adverse events (AEs), AEs that led to dose adjustments or treatment discontinuation, AEs of potential clinical interest, treatment-related AEs (TRAEs), serious AEs (SAEs), and deaths were documented. One hundred seventy-nine patients were included in the first 5 years of observation; 118 of 179 patients had an AE of any grade, with the most common AEs being stomatitis (7.8%) and headache (7.3%). AEs caused dose adjustments in 56 patients (31.3%) and treatment discontinuation in nine patients (5%). AEs appeared to be more frequent and severe in children. On Tanner staging, all patients displayed signs of age-appropriate sexual maturation. Twenty-two of 106 female (20.8%) patients had menstrual cycle disorders. The most frequent TRAEs were stomatitis (6.7%) and aphthous mouth ulcer (5.6%). SAEs were reported in 54 patients (30.2%); the most frequent SAE was pneumonia (>3% patients; grade 2, 1.1%, and grade 3, 2.8%). Three deaths were reported, all in patients who had discontinued everolimus for more than 28 days, and none were thought to be related to everolimus according to the treating physicians. The PASS sub-study reflects the safety and tolerability of everolimus in the management of TSC in real-world routine clinical practice.

Differential ketogenic diet-induced shift in CSF lipid/carbohydrate metabolome of pediatric epilepsy patients with optimal vs. no anticonvulsant response: a pilot study.

BACKGROUND: The low carbohydrate, high fat ketogenic diet can be an effective anticonvulsant treatment in some pediatric patients with pharmacoresistant epilepsy. Its mechanism(s) of action, however, remain uncertain. Direct sampling of cerebrospinal fluid before and during metabolic therapy may reveal key changes associated with differential clinical outcomes. We characterized the relationship between seizure responsiveness and changes in lipid and carbohydrate metabolites. METHODS: We performed metabolomic analysis of cerebrospinal fluid samples taken before and during ketogenic diet treatment in patients with optimal response (100% seizure remission) and patients with no response (no seizure improvement) to search for differential diet effects in hallmark metabolic compounds in these two groups. Optimal responders and non-responders were similar in age range and included males and females. Seizure types and the etiologies or syndromes of epilepsy varied but did not appear to differ systematically between responders and non-responders. RESULTS: Analysis showed a strong effect of ketogenic diet treatment on the cerebrospinal fluid metabolome. Longitudinal and between-subjects analyses revealed that many lipids and carbohydrates were changed significantly by ketogenic diet, with changes typically being of larger magnitude in responders. Notably, responders had more robust changes in glucose and the ketone bodies ß-hydroxybutyrate and acetoacetate than non-responders; conversely, non-responders had significant increases in fructose and sorbose, which did not occur in responders. CONCLUSIONS: The data suggest that a differential and stronger metabolic response to the ketogenic diet may predict a better anticonvulsant response, and such variability is likely due to inherent biological factors of individual patients. Strategies to boost the metabolic response may be beneficial.

Lissencephaly in an epilepsy cohort: Molecular, radiological and clinical aspects.

INTRODUCTION: Lissencephaly is a rare malformation of cortical development due to abnormal transmantle migration resulting in absent or reduced gyration. The lissencephaly spectrum consists of agyria, pachygyria and subcortical band heterotopia. In this study we compared genetic aetiology, neuroradiology, clinical phenotype and response to antiepileptic drugs in patients with epilepsy and lissencephaly spectrum malformations. METHODS: The study group consisted of 20 patients - 13 males and 7 females, aged 18 months to 21 years at the time of data collection. Genetic testing was performed by oligonucleotide array comparative genomic hybridization (microarray), multiplex ligation-dependent probe amplification (MLPA), targeted gene panels and whole exome/genome sequencing. All neuroradiological investigations were re-evaluated and the malformations were classified by the same neuroradiologist. Clinical features and response to anti-epileptic drugs (AEDs) were evaluated by retrospective review of medical records. RESULTS: In eleven patients (55%) mutations in PAFAH1B1 (LIS1) or variable microdeletions of 17p13.3 including the PAFAH1B1 gene were detected. Four patients (20%) had tubulin encoding gene mutations (TUBA1A, TUBG1 and TUBGCP6). Mutations in DCX, DYNC1H1, ADGRG1 and WDR62 were identified in single patients. In one patient, a possibly pathogenic intragenic deletion in TRIO was detected. A clear radiologic distinction could be made between tubulinopathies and PAFAH1B1 related lissencephaly. The majority of the patients had therapy resistant epilepsy and epileptic spasms was the most prominent seizure type. The best therapeutic response to seizure control in our cohort was obtained by the ketogenic diet, vigabatrin, clobazam, phenobarbital and valproate. CONCLUSION: The most common genetic aetiologies in our cohort of 20 individuals with epilepsy and lissencephaly spectrum were intragenic deletions or single nucleotide mutations in PAFAH1B1 or larger deletions in 17p13.3, encompassing PAFAH1B1, followed by mutations in tubulin encoding genes. Radiological findings could reliably predict molecular results only in agyria with a posterior to anterior gradient. Radiological and molecular findings did not correlate consistently with severity of clinical outcome or therapeutic response.

Renal Manifestations of Tuberous Sclerosis Complex: Key Findings From the Final Analysis of the TOSCA Study Focussing Mainly on Renal Angiomyolipomas.

Renal angiomyolipomas are one of the most common renal manifestations in patients with tuberous sclerosis complex (TSC), with potentially life-threatening complications and a poor prognosis. Despite the considerable progress in understanding TSC-associated renal angiomyolipomas, there are no large scale real-world data. The aim of our present study was to describe in detail the prevalence and outcome of renal angiomyolipomas in patients with TSC, enrolled into the TuberOus SClerosis registry to increase disease Awareness (TOSCA) from 170 sites across 31 countries worldwide. We also sought to evaluate the relationship of TSC-associated renal angiomyolipomas with age, gender and genotype. The potential risk factors for renal angiomyolipoma-related bleeding and chronic kidney disease (CKD) were studied in patients who participated in the TOSCA renal angiomyolipoma substudy. Of the 2,211 eligible patients, 1,062 (48%) reported a history of renal angiomyolipomas. The median age of TSC diagnosis for the all subjects (n = 2,211) was 1 year. The median age of diagnosis of renal angiomyolipoma in the 1,062 patients was 13 years. Renal angiomyolipomas were significantly more prevalent in female patients (p < 0.0001). Rates of angiomyolipomas >3 cm (p = 0.0119), growing lesions (p = 0.0439), and interventions for angiomyolipomas (p = 0.0058) were also higher in females than males. Pre-emptive intervention for renal angiomyolipomas with embolisation, surgery, or mammalian target of rapamycin (mTOR) inhibitor may have abolished the gender difference in impaired renal function, hypertension, and other complications. The rate of interventions for angiomyolipomas was less common in children than in adults, but interventions were reported in all age groups. In the substudy of 76 patients the complication rate was too low to be useful in predicting risk for more severe CKD. In addition, in this substudy no patient had a renal hemorrhage after commencing on an mTOR inhibitor. Our findings confirmed that renal angiomyolipomas in subjects with TSC1 mutations develop on average at the later age, are relatively smaller in size and less likely to be growing; however, by age 40 years, no difference was observed in the percentage of patients with TSC1 and TSC2 mutations needing intervention. The peak of appearance of new renal angiomyolipomas was observed in patients aged between 18 and 40 years, but, given that angiomyolipomas can occur later, lifelong surveillance is necessary. We found that pre-emptive intervention was dramatically successful in altering the outcome compared to historical controls; with high pre-emptive intervention rates but low rates of bleeding and other complications. This validates the policy of surveillance and pre-emptive intervention recommended by clinical guidelines.

Burden of Illness and Quality of Life in Tuberous Sclerosis Complex: Findings From the TOSCA Study.

Research on tuberous sclerosis complex (TSC) to date has focused mainly on the physical manifestations of the disease. In contrast, the psychosocial impact of TSC has received far less attention. The aim of this study was therefore to examine the impact of TSC on health, quality of life (QoL), and psychosocial well-being of individuals with TSC and their families. Questionnaires with disease-specific questions on burden of illness (BOI) and validated QoL questionnaires were used. After completion of additional informed consent, we included 143 individuals who participated in the TOSCA (TuberOus SClerosis registry to increase disease Awareness) study. Our results highlighted the substantial burden of TSC on the personal lives of individuals with TSC and their families. Nearly half of the patients experienced negative progress in their education or career due to TSC (42.1%), as well as many of their caregivers (17.6% employed; 58.8% unemployed). Most caregivers (76.5%) indicated that TSC affected family life, and social and working relationships. Further, well-coordinated care was lacking: a smooth transition from pediatric to adult care was mentioned by only 36.8% of adult patients, and financial, social, and psychological support in 21.1, 0, and 7.9%, respectively. In addition, the moderate rates of pain/discomfort (35%) and anxiety/depression (43.4%) reported across all ages and levels of disease demonstrate the high BOI and low QoL in this vulnerable population.

Tuberous Sclerosis Complex-Associated Neuropsychiatric Disorders (TAND): New Findings on Age, Sex, and Genotype in Relation to Intellectual Phenotype.

Background: Knowledge is increasing about TSC-Associated Neuropsychiatric Disorders (TAND), but little is known about the potentially confounding effects of intellectual ability (IA) on the rates of TAND across age, sex, and genotype. We evaluated TAND in (a) children vs. adults, (b) males vs. females, and (c) TSC1 vs. TSC2 mutations, after stratification for levels of IA, in a large, international cohort. Methods: Individuals of any age with a documented visit for TSC in the 12 months prior to enrolment were included. Frequency and percentages of baseline TAND manifestations were presented by categories of IA (no intellectual disability [ID, intelligence quotient (IQ)>70]; mild ID [IQ 50-70]; moderate-to-profound ID [IQ<50]). Chi-square tests were used to test associations between ID and TAND manifestations. The association between TAND and age (children vs. adults), sex (male vs. female), and genotype (TSC1 vs. TSC2) stratified by IA levels were examined using the Cochran-Mantel-Haenszel tests. Results: Eight hundred and ninety four of the 2,211 participants had formal IQ assessments. There was a significant association (P < 0.05) between levels of IA and the majority of TAND manifestations, except impulsivity (P = 0.12), overactivity (P = 0.26), mood swings (P = 0.08), hallucinations (P = 0.20), psychosis (P = 0.06), depressive disorder (P = 0.23), and anxiety disorder (P = 0.65). Once controlled for IA, children had higher rates of overactivity, but most behavioral difficulties were higher in adults. At the psychiatric level, attention deficit hyperactivity disorder (ADHD) was seen at higher rates in children while anxiety and depressive disorders were observed at higher rates in adults. Compared to females, males showed significantly higher rates of impulsivity and overactivity, as well as autism spectrum disorder (ASD) and ADHD. No significant age or sex differences were observed for academic difficulties or neuropsychological deficits. After controlling for IA no genotype-TAND associations were observed, except for higher rates of self-injury in individuals with TSC2 mutations. Conclusions: Findings suggest IA as risk marker for most TAND manifestations. We provide the first evidence of male preponderance of ASD and ADHD in individuals with TSC. The study also confirms the association between TSC2 and IA but, once controlling for IA, disproves the previously reported TSC2 association with ASD and with most other TAND manifestations.

Evidence-based anti-seizure monotherapy in newly diagnosed epilepsy: A new approach.

OBJECTIVES: To describe the process and results of the updated Swedish practice guidelines for monotherapy in epilepsy. MATERIALS AND METHODS: The Swedish Medical Products Agency led the process together with medical experts. Evidence rating in accordance with the International League Against Epilepsy (ILAE) template was linked to the Cochrane group's GRADE system. Evidence from recently published trials and meta-analyses was added. A national expert panel participated in the project and contributed their clinical experience. RESULTS: In seizures with focal onset, carbamazepine, lamotrigine, or levetiracetam is recommended for children and adults (ILAE level A-C for adults/Cochrane level strong for children and adults). Oxcarbazepine is an alternative for children, although its level A evidence, in a single class I trial, could relate to poor phenytoin tolerability. Eslicarbazepine acetate, lacosamide, and zonisamide are alternatives for adults and gabapentin for the elderly (ILAE level A). Carbamazepine is not a first choice for the elderly due to its high potential for interactions. In generalized epilepsy with tonic-clonic seizures (GTC), lamotrigine, levetiracetam, and sodium valproate are recommended for children and adults (ILAE level C-D/Cochrane level moderate-strong) although sodium valproate is contraindicated in girls and women of childbearing age unless special considerations are met. Ethosuximide is the first choice in absence epilepsy without GTC (ILAE level A). CONCLUSIONS: Lamotrigine and levetiracetam can be used as first choice for focal seizures and generalized epilepsy with GTC, suitable in all age-groups and for both men and women. Recommendations for GTC seizures have lower evidence than those for focal seizures.

The TOSCA Registry for Tuberous Sclerosis-Lessons Learnt for Future Registry Development in Rare and Complex Diseases.

Introduction: The TuberOus SClerosis registry to increase disease Awareness (TOSCA) is an international disease registry designed to provide insights into the clinical characteristics of patients with Tuberous Sclerosis Complex (TSC). The aims of this study were to identify issues that arose during the design, execution, and publication phases of TOSCA, and to reflect on lessons learnt that may guide future registries in rare and complex diseases. Methods: A questionnaire was designed to identify the strengths, weaknesses, and issues that arose at any stage of development and implementation of the TOSCA registry. The questionnaire contained 225 questions distributed in 7 sections (identification of issues during registry planning, during the operation of the registry, during data analysis, during the publication of the results, other issues, assessment of lessons learnt, and additional comments), and was sent by e-mail to 511 people involved in the registry, including 28 members of the Scientific Advisory Board (SAB), 162 principal investigators (PIs), and 321 employees of the sponsor belonging to the medical department or that were clinical research associate (CRA). Questionnaires received within the 2 months from the initial mailing were included in the analysis. Results: A total of 53 (10.4%) questionnaires were received (64.3% for SAB members, 12.3% for PIs and 4.7% for employees of the sponsor), and the overall completeness rate for closed questions was 87.6%. The most common issues identified were the limited duration of the registry (38%) and issues related to handling of missing data (32%). In addition, 25% of the respondents commented that biases might have compromised the validity of the results. More than 80% of the respondents reported that the registry improved the knowledge on the natural history and manifestations of TSC, increased disease awareness and helped to identify relevant information for clinical research in TSC. Conclusions: This analysis shows the importance of registries as a powerful tool to increase disease awareness, to produce real-world evidence, and to generate questions for future research. However, there is a need to implement strategies to ensure patient retention and long-term sustainability of patient registries, to improve data quality, and to reduce biases.

Treatment Patterns and Use of Resources in Patients With Tuberous Sclerosis Complex: Insights From the TOSCA Registry.

Tuberous Sclerosis Complex (TSC) is a rare autosomal-dominant disorder caused by mutations in the TSC1 or TSC2 genes. Patients with TSC may suffer from a wide range of clinical manifestations; however, the burden of TSC and its impact on healthcare resources needed for its management remain unknown. Besides, the use of resources might vary across countries depending on the country-specific clinical practice. The aim of this paper is to describe the use of TSC-related resources and treatment patterns within the TOSCA registry. A total of 2,214 patients with TSC from 31 countries were enrolled and had a follow-up of up to 5 years. A search was conducted to identify the variables containing both medical and non-medical resource use information within TOSCA. This search was performed both at the level of the core project as well as at the level of the research projects on epilepsy, subependymal giant cell astrocytoma (SEGA), lymphangioleiomyomatosis (LAM), and renal angiomyolipoma (rAML) taking into account the timepoints of the study, age groups, and countries. Data from the quality of life (QoL) research project were analyzed by type of visit and age at enrollment. Treatments varied greatly depending on the clinical manifestation, timepoint in the study, and age groups. GAB Aergics were the most prescribed drugs for epilepsy, and mTOR inhibitors are dramatically replacing surgery in patients with SEGA, despite current recommendations proposing both treatment options. mTOR inhibitors are also becoming common treatments in rAML and LAM patients. Forty-two out of the 143 patients (29.4%) who participated in the QoL research project reported inpatient stays over the last year. Data from non-medical resource use showed the critical impact of TSC on job status and capacity. Disability allowances were more common in children than adults (51.1% vs 38.2%). Psychological counseling, social services and social worker services were needed by <15% of the patients, regardless of age. The long-term nature, together with the variability in its clinical manifestations, makes TSC a complex and resource-demanding disease. The present study shows a comprehensive picture of the resource use implications of TSC.

Clinical Characteristics of Subependymal Giant Cell Astrocytoma in Tuberous Sclerosis Complex.

Background: This study evaluated the characteristics of subependymal giant cell astrocytoma (SEGA) in patients with tuberous sclerosis complex (TSC) entered into the TuberOus SClerosis registry to increase disease Awareness (TOSCA). Methods: The study was conducted at 170 sites across 31 countries. Data from patients of any age with a documented clinical visit for TSC in the 12 months preceding enrollment or those newly diagnosed with TSC were entered. Results: SEGA were reported in 554 of 2,216 patients (25%). Median age at diagnosis of SEGA was 8 years (range, <1-51), with 18.1% diagnosed after age 18 years. SEGA growth occurred in 22.7% of patients aged ≤ 18 years and in 11.6% of patients aged > 18 years. SEGA were symptomatic in 42.1% of patients. Symptoms included increased seizure frequency (15.8%), behavioural disturbance (11.9%), and regression/loss of cognitive skills (9.9%), in addition to those typically associated with increased intracranial pressure. SEGA were significantly more frequent in patients with TSC2 compared to TSC1 variants (33.7 vs. 13.2 %, p < 0.0001). Main treatment modalities included surgery (59.6%) and mammalian target of rapamycin (mTOR) inhibitors (49%). Conclusions: Although SEGA diagnosis and growth typically occurs during childhood, SEGA can occur and grow in both infants and adults.

The gut microbiome and epilepsy.

Recently, evidence from both animal studies and human cases has emerged that a dysbiosis in the gut may be associated with certain forms of epilepsy. The ketogenic diet is an alternative treatment of drug-resistant epilepsy, although its precise mechanism of action has been unclear. It has now been shown that the ketogenic diet changes the composition and function of the gut microbiome in epilepsy patients. Studies in mice have demonstrated that the gut microbiota was necessary for the therapeutic effect of the diet and a mechanism of action has been proposed, providing new potential strategies for treatment. Further studies are needed to confirm the clinical relevance of this discovery. Below, we will discuss the scientific evidence of the role of the microbiome in seizure disorders, the impact of the ketogenic diet on the intestinal microbiota as well as the interactions described between commonly used antiepileptic drugs and intestinal microbial communities. We also discuss the potential of modulators of the gut microbiota as possible future anti-seizure therapeutics.

Epilepsy in tuberous sclerosis complex: Findings from the TOSCA Study.

OBJECTIVE: To present the baseline data of the international TuberOus SClerosis registry to increase disease Awareness (TOSCA) with emphasis on the characteristics of epilepsies associated with tuberous sclerosis complex (TSC). METHODS: Retrospective and prospective patients' data on all aspects of TSC were collected from multiple countries worldwide. Epilepsy variables included seizure type, age at onset, type of treatment, and treatment outcomes and association with genotype, seizures control, and intellectual disability. As for noninterventional registries, the study protocol did not specify any particular clinical instruments, laboratory investigations, or intervention. Evaluations included those required for diagnosis and management following local best practice. RESULTS: Epilepsy was reported in 83.6% of patients (1852/2216) at baseline; 38.9% presented with infantile spasms and 67.5% with focal seizures. The mean age at diagnosis of infantile spasms was 0.4 year (median <1 year; range <1-30 years) and at diagnosis of focal seizures was 2.7 years (median 1 year; range <1-66 years). A total of 1469 patients (79.3%) were diagnosed with epilepsy <2 years. The rate of infantile spasms was higher in patients with a TSC 2 mutation than in patients with a TSC1 mutation (47.3% vs 23%). É£-aminobutyric acid (GABA)ergic drugs were the most common treatment modality for both infantile spasms (78.7%) and focal seizures (65.5%). Infantile spasms and focal seizures were controlled in 76.3% and 58.2% of patients, respectively. Control of seizures was associated with lower rates of intellectual disability in both groups. SIGNIFICANCE: This registry reports the largest international cohort of patients with TSC. Findings confirmed the typical onset pattern of infantile spasms and other focal seizures in the first 2 years of life, and the high rates of infantile spasms in patients with TSC2 mutation. Our results underscored the occurrence of focal seizures at all ages, including an onset that preceded emergence of infantile spasms. Seizure control was shown to be associated with lower rates of intellectual disability but did not preclude the presence of intellectual disability.