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

Tuberous Sclerosis Complex: An updated in the treatment of epilepsy for early careers

Tuberous Sclerosis Complex (TSC) is a rare autosomal dominant disorder that is characterized by multisystem involvement and significant neurological manifestations. TSC1 and TSC2 pathogenic variants lead to hyperactivation of the mammalian target of rapamycin (mTOR) pathway, which disrupts cellular growth and differentiation. Epilepsy, affecting 85-90% of individuals with TSC, often presents within the first year of life and is commonly resistant to conventional therapies. This paper provides a comprehensive overview of the diagnostic criteria, pathophysiology, and current treatment strategies for TSC-associated epilepsy, including pharmacological approaches such as vigabatrin, cannabidiol, and mTOR inhibitors, as well as non-pharmacological interventions such as ketogenic diet and epilepsy surgery. Preventive strategies, highlighted by robust trials, delay seizure onset and reduce its severity but have a limited impact on neurodevelopmental outcomes. Challenges include the heterogeneity of cortical tubers, suboptimal seizure control with existing therapies, and underutilization of neuropsychiatric care for TSC-associated neuropsychiatric disorders. Advances in biomarkers, precision medicine, and surgical techniques have paved the way for personalized treatment approaches. Future research providing earlier detection strategies and integrating therapies targeting both the neurological and behavioral dimensions of TSC is ongoing. By addressing these needs, clinicians and researchers can enhance the quality of life and developmental outcomes of individuals with TSC.

Genotype-phenotype correlation of ODLURO syndrome comorbid epilepsy associated with KMT2E variations: Report on a novel case and systematic literature review

BACKGROUND

O'Donnell-Luria-Rodan (ODLURO) syndrome is a newly described neurodevelopmental disorder caused by a pathogenic KMT2E variant. The primary clinical phenotypes include developmental delay, intellectual disability (ID), and epilepsy. Epilepsy, observed in 29% of affected individuals, has not been thoroughly investigated. In this study, we describe the phenotypes and genetic profiles of patients with ODLURO syndrome and epilepsy.

METHODS

We summarized and analyzed data from 30 patients with ODLURO syndrome and epilepsy from the systematic literature and DECIPHER database. Information regarding seizure classification, brain MRI findings, antiseizure medications, and genetics variations was collected and analyzed retrospectively.

RESULTS

The risk factors associated with epilepsy in ODLURO syndrome remain unclear, and clinical heterogeneity exists. While focal seizures are most prevalent, various epilepsy classifications are observed. Brain MRI findings indicated that cerebral atrophy and cystic changes were common, though no correlation with epilepsy was established. Among ten individuals with a record of antiseizure medication, approximately 70% required two or more antiseizure medications.

CONCLUSIONS

A clear genotype-phenotype correlation remains elusive even among individuals with the same KMT2E variation. The pathogenesis of epilepsy associated with KMT2E variation is complex and necessitates further molecular genetic studies to elucidate the mechanisms underlying these genetic disorders. This research provides essential evidence for specific and individualized treatment approaches.

Intellectual disability and autistic behavior and their modifying factors in children with tuberous sclerosis complex

Tuberous sclerosis complex (TSC) is classified among developmental epileptic encephalopathies, where epilepsy is often associated with comorbidities such as intellectual disability and autistic behavior. The recently introduced term TAND (TSC-associated neuropsychiatric disorders) encompasses the wide range of cognitive, behavioral, psychiatric, and psychosocial manifestations seen in TSC. The severity of these comorbidities is influenced by several factors, including the TSC1/TSC2 genotype, the age of epilepsy onset, the number, volume and type of cortical tubers, the interval between epilepsy onset and treatment initiation, and the presence of infantile spasms, hypsarrhythmia, or drug-resistant epilepsy. Clinical, genetic, EEG, and neuroimaging biomarkers enable the early identification of infants at high risk of developing intellectual disability or autism spectrum disorder. Early preventive intervention targeting seizures and tailored strategies during a sensitive developmental window may modify these contributing factors, leading to improved neurodevelopmental outcomes in infants with TSC.

Altered cortical excitability in tuberous sclerosis and the effect of mTOR inhibitors: An intracranial electrical stimulation study

OBJECTIVE

We used electrical stimulation mapping (ESM) of functional responses, after-discharges (ADs), and unwanted electrical stimulation-induced seizures (EIS) to explore differences in cortical excitability in tuberous sclerosis complex (TSC) patients on mTOR inhibitors, TSC patients not on mTOR inhibitors, and drug-resistant epilepsy (DRE) of unknown etiology.

METHODS

In 20 patients with TSC and 10 patients with DRE of unknown etiology, incidence and current thresholds of physiologic (language and motor) and pathologic (ADs, EIS) responses were analyzed using mixed effects models against disease phenotype (TSC vs unknown) and use of mTOR inhibitors.

RESULTS

Patients with TSC showed a higher incidence and required a lower threshold current to elicit motor responses and ADs compared to those with DRE of unknown etiology. In TSC patients, mTOR inhibitors increased the threshold for motor responses and ADs, and decreased the incidence of face motor responses, language responses, and ADs.

CONCLUSIONS

TSC patients exhibit higher physiologic and pathologic cortical excitability evidenced by a higher incidence and lower current thresholds of ESM responses, which appears to be mitigated by mTOR inhibitors.

SIGNIFICANCE

To our knowledge, this is the first study providing direct intracranial evidence for altered cortical excitability in TSC and the corrective effect of mTOR inhibitors.

Disease Burden and Associated Factors in Chinese Patients with Tuberous Sclerosis Complex: Results of a Patient and Caregiver Survey

Objective

Tuberous Sclerosis Complex (TSC) is a rare autosomal dominant genetic disorder primarily characterized by neurological symptoms. This study aimed to evaluate the current disease burden in Chinese patients with TSC and to identify the potential influencing factors.

Methods

A cross-sectional study design was employed using an online questionnaire survey. The questionnaire covered demographics, diagnosis and treatment status, medication use, and disease burden. Descriptive statistics were used to summarize the data, and multivariate logistic regression analysis was performed to examine factors influencing the disease burden in pediatric and adult patients with TSC.

Results

The survey involved a total of 840 patients or their caregivers, comprising 691 pediatric and 149 adult patients, with an average age at diagnosis of 1.77 years for pediatric patients and 15.28 years for adult patients. The most prevalent clinical manifestations were seizures (75.1% in pediatric, 43.6% in adult), brain calcification spots/nodules (87.8% pediatric, 82.5% adult), and hypomelanotic macules (89.5% pediatric, 72.4% adult). Intellectual disability (ID) was reported in 29.6% of pediatric patients and 19.4% of adult patients. Catastrophic health expenditure (CHE) was reported by 29.6% of patients. Factors influencing the disease burden included ID, misdiagnosis, and use of anti-seizure medications (ASMs) and mammalian target of rapamycin (mTOR) inhibitors for pediatric patients or educational attainment, medication use (such as ASMs and mTOR inhibitors), and ID for adult patients.

Conclusion

The study demonstrated that Chinese patients with TSC are confronted with a considerable disease burden. Comprehensive care strategies, tailored educational support for pediatric patients, and multidisciplinary approaches for early diagnosis are crucial for managing TSC.

Treatment of Seizures in People with Intellectual Disability

There is a synergistic relationship between epilepsy and intellectual disability (ID), and the approach to managing people with these conditions needs to be holistic. Epilepsy is the main co-morbidity associated with ID, and clinical presentation tends to be complex, associated with higher rates of treatment resistance, multi-morbidity and premature mortality. Despite this relationship, there is limited level 1 evidence to inform treatment choice for this vulnerable population. This review updates the current evidence base for anti-seizure medication (ASM) prescribing for people with ID. Recommendations are made on the basis of evidence and expert clinical opinion and summarised into a Traffic Light System for accessibility. This review builds on work developed through UK's Royal College of Psychiatrists, Faculty of Intellectual Disability Psychiatry and includes newer pragmatic data from the Cornwall UK Ep-ID Research Register, a national research register for England and Wales that has been in existence for the last 10 years. The Register acts as a source for an in-depth exploration of the evidence base for prescribing 'newer' (third generation, specifically post-2004) ASMs. Its findings are discussed and compared. A practical approach to prescribing and choosing ASMs is recommended on the based evidence. This approach considers the drug profile, including adverse effects and clinical characteristics. The review also details newer specialist ASMs restricted to certain epilepsy syndromes, and potential future ASMs that may be available soon. For completeness, we also explore non-pharmacological interventions, including surgeries, to support epilepsy management.

Vigabatrin-associated brain magnetic resonance imaging abnormalities and clinical symptoms in infants with tuberous sclerosis complex

OBJECTIVE

Previous retrospective studies have reported vigabatrin-associated brain abnormalities on magnetic resonance imaging (VABAM), although clinical impact is unknown. We evaluated the association between vigabatrin and predefined brain magnetic resonance imaging (MRI) changes in a large homogenous tuberous sclerosis complex (TSC) cohort and assessed to what extent VABAM-related symptoms were reported in TSC infants.

METHODS

The Dutch TSC Registry and the EPISTOP cohort provided retrospective and prospective data from 80 TSC patients treated with vigabatrin (VGB) before the age of 2 years and 23 TSC patients without VGB. Twenty-nine age-matched non-TSC epilepsy patients not receiving VGB were included as controls. VABAM, specified as T2/fluid-attenuated inversion recovery hyperintensity or diffusion restriction in predefined brain areas, were examined on brain MRI before, during, and after VGB, and once in the controls (at approximately age 2 years). Additionally, the presence of VABAM accompanying symptoms was evaluated.

RESULTS

Prevalence of VABAM in VGB-treated TSC patients was 35.5%. VABAM-like abnormalities were observed in 13.5% of all patients without VGB. VGB was significantly associated with VABAM (risk ratio [RR] = 3.57, 95% confidence interval [CI] = 1.43-6.39), whereas TSC and refractory epilepsy were not. In all 13 VGB-treated patients with VABAM for whom posttreatment MRIs were available, VABAM entirely resolved after VGB discontinuation. The prevalence of symptoms was 11.7% in patients with VABAM or VABAM-like MRI abnormalities and 4.3% in those without, implicating no significant association (RR = 2.76, 95% CI = .68-8.77).

SIGNIFICANCE

VABAM are common in VGB-treated TSC infants; however, VABAM-like abnormalities also occurred in children without either VGB or TSC. The cause of these MRI changes is unknown. Possible contributing factors are abnormal myelination, underlying etiology, recurrent seizures, and other antiseizure medication. Furthermore, the presence of VABAM (or VABAM-like abnormalities) did not appear to be associated with clinical symptoms. This study confirms that the well-known antiseizure effects of VGB outweigh the risk of VABAM and related symptoms.

Stereo-EEG around the world: State of the art in Italy

Stereo-EEG is not just a diagnostic examination but a complex methodology, requiring an accurate synthesis of many data (anatomical, clinical, neurophysiological, cognitive, metabolic, and genetic). The implantation scheme is decided based on a hypothesis (or hypotheses) of epileptogenic zone localization. Subsequently, intracerebral electrical stimulation is used to define the extent of highly functional cortical regions and to reproduce the clinical symptoms and signs associated with seizures. Finally, stereo-EEG-guided thermocoagulation is used, with the dual purpose of stopping/reducing the seizures and determining the prognosis of possible resective (curative) surgery. The centers in Italy that use stereo-EEG derive from the French school of Bancaud and Talairach. Nevertheless, each one has interpreted, on the basis of its own specificity and talent, a new methodology and philosophy of implantation. The present work presents the state of the art of stereo-EEG use in Italy, with detail of the stereo-EEG program of the Munari center in Milano, as well as those of Florence, Bologna and Rome.

Evolving treatment strategies for early-life seizures in Tuberous Sclerosis Complex: A review and treatment algorithm

Tuberous sclerosis Complex (TSC) is a genetic disorder characterized by multisystem involvement, with epilepsy affecting 80-90% of patients, often beginning in infancy. Early-life seizures in TSC are associated with poor neurodevelopmental outcomes, underscoring the importance of timely and effective management. This review explores the evolving treatment landscape for TSC-associated seizures in young children, focusing on three recently approved or license-expanded therapies: vigabatrin, everolimus, and cannabidiol. The efficacy and safety profiles of these treatments are examined based on clinical trials and real-world evidence, with a focus on their use in treating seizures in young children. The preemptive use of vigabatrin in clinical studies has also been carefully reviewed. A treatment algorithm is proposed, emphasizing early diagnosis, prompt initiation of appropriate therapy, and a stepwise approach to managing both infantile spasms and focal seizures. The algorithm incorporates these newer therapies alongside traditional antiseizure medications and non-pharmacological approaches. Challenges in optimizing treatment strategies, minimizing side effects, and improving long-term outcomes are discussed. This review aims to guide clinicians in navigating the complex landscape of early-life seizures associated with TSC, ultimately striving for improved seizure control and better developmental outcomes in this vulnerable population.

Prenatal mTOR Inhibitors in Tuberous Sclerosis Complex: Current Insights and Future Directions

Background: Tuberous sclerosis complex (TSC) can present prenatally, often with cardiac rhabdomyomas, which, if large, may cause complications such as hydrops fetalis and reduced cardiac output. Prenatal treatment of these lesions with mTOR inhibitors, approved for other TSC manifestations, is under investigation. We hypothesize that mTOR inhibitors could help manage or prevent other TSC-related conditions, particularly neurological issues like epilepsy and CNS lesions, potentially improving neurodevelopmental outcomes. However, the safety of prenatal mTOR treatment remains a concern, especially for foetal development, and limited data are available on neurological outcomes. Methods: We conducted a literature review using PubMed, EMBASE, and Cochrane CENTRAL, focusing on studies involving mTOR inhibitors for prenatal TSC management. The search included case reports and series involving pregnant women diagnosed with TSC or early manifestations like cardiac rhabdomyomas. Keywords included "mTOR Inhibitor", "Rapamycin", "tuberous sclerosis complex", "prenatal", and "rhabdomyoma". Results: Three prenatal mouse studies and eight papers reporting on ten pregnant women treated with mTOR inhibitors were identified. Conclusions: The literature confirms that prenatal mTOR inhibitors may reduce cardiac rhabdomyomas. However, further studies are needed to explore their broader potential, particularly in preventing neurological complications, while carefully considering their impact on intrauterine growth and neurodevelopment.

Therapeutic Approaches to Tuberous Sclerosis Complex: From Available Therapies to Promising Drug Targets

Tuberous sclerosis complex (TSC) is a rare multisystem disorder caused by heterozygous loss-of-function pathogenic variants in the tumour suppressor genes TSC1 and TSC2 encoding the tuberin and hamartin proteins, respectively. Both TSC1 and TSC2 inhibit the mammalian target of rapamycin (mTOR) complexes pathway, which is crucial for cell proliferation, growth, and differentiation, and is stimulated by various energy sources and hormonal signaling pathways. Pathogenic variants in TSC1 and TSC2 lead to mTORC1 hyperactivation, producing benign tumours in multiple organs, including the brain and kidneys, and drug-resistant epilepsy, a typical sign of TSC. Brain tumours, sudden unexpected death from epilepsy, and respiratory conditions are the three leading causes of morbidity and mortality. Even though several therapeutic options are available for the treatment of TSC, there is further need for a better understanding of the pathophysiological basis of the neurologic and other manifestations seen in TSC, and for novel therapeutic approaches. This review provides an overview of the main current therapies for TSC and discusses recent studies highlighting the repurposing of approved drugs and the emerging role of novel targets for future drug design.

Developmental and epileptic encephalopathies

Developmental and epileptic encephalopathies, the most severe group of epilepsies, are characterized by seizures and frequent epileptiform activity associated with developmental slowing or regression. Onset typically occurs in infancy or childhood and includes many well-defined epilepsy syndromes. Patients have wide-ranging comorbidities including intellectual disability, psychiatric features, such as autism spectrum disorder and behavioural problems, movement and musculoskeletal disorders, gastrointestinal and sleep problems, together with an increased mortality rate. Problems change with age and patients require substantial support throughout life, placing a high psychosocial burden on parents, carers and the community. In many patients, the aetiology can be identified, and a genetic cause is found in >50% of patients using next-generation sequencing technologies. More than 900 genes have been identified as monogenic causes of developmental and epileptic encephalopathies and many cell components and processes have been implicated in their pathophysiology, including ion channels and transporters, synaptic proteins, cell signalling and metabolism and epigenetic regulation. Polygenic risk score analyses have shown that common variants also contribute to phenotypic variability. Holistic management, which encompasses antiseizure therapies and care for multimorbidities, is determined both by epilepsy syndrome and aetiology. Identification of the underlying aetiology enables the development of precision medicines to improve the long-term outcome of patients with these devastating diseases.

Modeling mTORopathy-related epilepsy in cultured murine hippocampal neurons using the multi-electrode array

The mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway is a ubiquitous cellular pathway. mTORopathies, a group of disorders characterized by hyperactivity of the mTORC1 pathway, illustrate the prominent role of the mTOR pathway in disease pathology, often profoundly affecting the central nervous system. One of the most debilitating symptoms of mTORopathies is drug-resistant epilepsy, emphasizing the urgent need for a deeper understanding of disease mechanisms to develop novel anti-epileptic drugs. In this study, we explored the multiwell Multi-electrode array (MEA) system as a tool to identify robust network activity parameters in an approach to model mTORopathy-related epilepsy in vitro. To this extent, we cultured mouse primary hippocampal neurons on the multiwell MEA to identify robust network activity phenotypes in mTORC1-hyperactive neuronal networks. mTOR-hyperactivity was induced either through deletion of Tsc1 or overexpression of a constitutively active RHEB variant identified in patients, RHEBp.P37L. mTORC1 dependency of the phenotypes was assessed using rapamycin, and vigabatrin was applied to treat epilepsy-like phenotypes. We show that hyperactivity of the mTORC1 pathway leads to aberrant network activity. In both the Tsc1-KO and RHEB-p.P37L models, we identified changes in network synchronicity, rhythmicity, and burst characteristics. The presence of these phenotypes is prevented upon early treatment with the mTORC1-inhibitor rapamycin. Application of rapamycin in mature neuronal cultures could only partially rescue the network activity phenotypes. Additionally, treatment with the anti-epileptic drug vigabatrin reduced network activity and restored burst characteristics. Taken together, we showed that mTORC1-hyperactive neuronal cultures on the multiwell MEA system present reliable network activity phenotypes that can be used as an assay to explore the potency of new drug treatments targeting epilepsy in mTORopathy patients and may give more insights into the pathophysiological mechanisms underlying epilepsy in these patients.

Have epilepsy outcomes changed for children with tuberous sclerosis complex in Queensland, Australia?

OBJECTIVE

Historically, epilepsy has been the most frequently presenting feature of tuberous sclerosis complex (TSC). Advances in TSC health care have occurred over the past decade; thus, we studied whether TSC epilepsy outcomes have changed.

METHOD

A retrospective chart review was undertaken for all children with TSC in Queensland, Australia. Epilepsy outcome and TSC diagnosis data were extracted, and data were compared between children born before 2012 with those born in or after 2012.

RESULTS

In this retrospective cohort, TSC diagnosis in children born in or after 2012 is now predominantly antenatal (51%, p < .05). Most patients with epilepsy are now known to have TSC before they develop epilepsy. Despite earlier TSC diagnosis, the frequency of epilepsy (85%) has not changed (p = .92), but diagnosis trends toward an earlier age (median = 3 months for patients born in or after 2012 vs. 5.5 months for those born before 2012, p = .23). Most (95%) patients had focal seizures as their initial clinical seizure type; it was rare (5%) for epileptic spasms (ES) to be the initial seizure type. The frequency of ES was lower in patients born in or after 2012 (36% vs. 50%, p = .27). Infantile (<24 months) onset ES was not associated with worse epilepsy outcome. Late onset ES was seen in 14%, and these patients had a lower rate of epilepsy remission. Lennox-Gastaut syndrome was seen in 7%. Febrile/illness-related status epilepticus occurred in 12% of patients, between 1 and 4 years of age. Despite many (78%) patients having multiple daily seizures at maximal seizure frequency, and 74% meeting criteria for treatment-refractory epilepsy, most patients achieved epilepsy remission (66%), either with epilepsy surgery (47%) or with age (53%). At the time of inclusion in this study, only 21% of patients had uncontrolled frequent (daily to 3 monthly) seizures and 14% had uncontrolled infrequent (3 monthly to <2 yearly) seizures.

SIGNIFICANCE

This study provides updated information that informs the counseling of parents of newly diagnosed pediatric TSC patients.

Epileptic seizures revealing tuberous sclerosis in a tropical environment: A study of 12 case series

Background

Epilepsy remains a significant public health concern in Sub-Saharan Africa (SSA) where diverse etiological factors contribute to its prevalence. Among these factors are conditions originating from the neuroectoderm, such as tuberous sclerosis. Insufficient medical attention and a lack of comprehensive multidisciplinary care contribute to its under-recognition.

Materials and methods

We conducted a retrospective descriptive study, involving 12 patients admitted to the neurology and pediatric departments of the University Hospital Ignace Deen between 2010 and 2022 due to recurring epileptic seizures. Subsequently, these patients were diagnosed with Tuberous sclerosis using the Schwartz 2007 criteria. The aim of this study is to reassess this condition from a clinical and paraclinical point of view in a tropical environment.

Results

Tuberous sclerosis, also known as Bourneville disease, was diagnosed in 12 patients exhibiting focal motor seizures and complex focal seizures likely associated with cortical and subcortical tubers detectable by EEG and neuroimaging, including CT and MRI. Delayed treatment resulted in varying degrees of mental decline. Additionally, some patients displayed cardiac hamartomas and intracranial posterior and anterior aneurysms as minor diagnostic indicators.

Conclusion

The study reveals a consistent clinical presentation accompanied by deteriorating neurological and psychological symptoms attributed to delayed multidisciplinary management. These findings are utilized to assess therapeutic strategies and prognostic outcomes.

The emotional burden of caring for patients with Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex-associated epilepsy: A qualitative study in Japan

INTRODUCTION

Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS) are rare, childhood-onset conditions associated with severe, treatment-resistant epilepsy and developmental issues, including motor and cognitive impairment. Tuberous sclerosis complex (TSC) is a rare genetic disease commonly associated with epilepsy and other neuropsychiatric disorders. This cross-sectional, interview-based study examined the qualitative impact of caring for patients with LGS, DS, and TSC-associated epilepsy on caregivers in Japan, from the perspective of both caregivers and physicians.

METHODS

The survey included a pre-interview worksheet to describe caregivers' emotional journeys, followed by a ≤ 60-minute one-on-one interview. Eligible participants were Japanese caregivers of patients with LGS, DS, or TSC treated for epilepsy symptoms, and Japan-residing pediatricians or neurologists treating ≥ 3 patients with LGS, DS, and/or TSC. Interview question responses were subjected to content analysis to identify the most common response tendencies and themes.

RESULTS

Twenty-six caregivers responded (mean [standard deviation (SD)] age, 45.9 [9.5] years; age range 29-68; 92 % female), caring for patients with LGS (n = 5), DS (n = 10), and TSC (n = 11); patient mean (SD) age, 13.6 (10.0) years; age range 2-44; 27 % adults; 50 % female. Nineteen physicians, treating patients with LGS (n = 9), DS (n = 7), and TSC (n = 10), participated. Caregivers and physicians generally aligned on the factors affecting caregivers' emotional states / quality of life (QoL). The most frequently reported caregiver emotions at the time of diagnosis were shock and discouragement, anxiety for the future, and relief at receiving a diagnosis. Negative emotions throughout disease progression up until the time of survey were mainly caused by worsening of seizures, burden of constant caregiving / lack of free time, and patient's developmental issues. Positive emotions were linked to effective treatment / reduced seizures; more free time owing to the use of facilities, services, or other caregiving support; and developmental progress. Physicians acknowledged that caregivers required consultation services to support their emotional needs. In terms of unmet needs, caregiver and physician responses were aligned on the insufficient availability of services/facilities, the lack of effective treatments, and the uncertainties of adult patient care.

CONCLUSIONS

Caregivers of patients with LGS, DS, or TSC-associated epilepsy in Japan reported a high degree of emotional burden related to frequent seizures, developmental issues, and constant caregiving. The burden of suboptimal treatment effectiveness, limited access to support services, and uncertainties in long-term care emphasize important unmet treatment needs.

Epidemiology and outcome of infantile spasms in Denmark in 1996-2019

PURPOSE

To investigate the treatment of infantile epileptic spasm syndrome (IESS) in Denmark.

METHODS

National retrospective cohort study of all patients born 1996-2019 who had a diagnosis of IESS in the National Patient Registry. Medical records were reviewed to evaluate the diagnosis. Patients were included if semiology was compatible with IESS, or if unclear semiology if there was an abnormal EEG or EEG with hypsarrhythmia.

RESULTS

Number of cases with a register based IESS diagnosis was 538. Medical records were unavailable in 48 and 164 did not fulfil the inclusion criteria. Thereby the cohort consisted of 326 children. Mean age at onset of IESS was 5.9 months and mean lead time to treatment was 26.6 days (SD= 63.5). Consistent with the Danish treatment guidelines most patients received vigabatrin as first treatment. In the cohort 44.7 % of patients solely received vigabatrin, whereas combined vigabatrin and corticosteroid was given to 28.3 % (either hydrocortisone or prednisolone). Other anti-seizure medication was given to 28.4 % within 90 days of IESS onset. Aetiology was prenatal (40.3 %), perinatal (10.5 %), postnatal (3.7 %), with unknown timing (10.2 %) or with unknown aetiology (33.5 %). The cohort was followed to a mean age of 8.2 years. At latest follow-up severe neurodevelopmental outcome was seen in 44.2 % and 76.4 % still had epilepsy. The incidence of IESS was 22 per 100.000 live births.

CONCLUSION

In Denmark treatment algorithm is based on start of treatment with vigabatrin. A total of 44.7 % became seizure free by vigabatrin. Neurodevelopmental outcome was severe. A national incidence could be established.

A multicenter, matched case-control analysis comparing burden of illness among patients with tuberous sclerosis complex related epilepsy, generalized idiopathic epilepsy, and focal epilepsy in Germany

BACKGROUND

Depending on the underlying etiology and epilepsy type, the burden of disease for patients with seizures can vary significantly. This analysis aimed to compare direct and indirect costs and quality of life (QoL) among adults with tuberous sclerosis complex (TSC) related with epilepsy, idiopathic generalized epilepsy (IGE), and focal epilepsy (FE) in Germany.

METHODS

Questionnaire responses from 92 patients with TSC and epilepsy were matched by age and gender, with responses from 92 patients with IGE and 92 patients with FE collected in independent studies. Comparisons were made across the main QoL components, direct costs (patient visits, medication usage, medical equipment, diagnostic procedures, ancillary treatments, and transport costs), indirect costs (employment, reduced working hours, missed days), and care level costs.

RESULTS

Across all three cohorts, mean total direct costs (TSC: €7602 [median €2620]; IGE: €1919 [median €446], P < 0.001; FE: €2598 [median €892], P < 0.001) and mean total indirect costs due to lost productivity over 3 months (TSC: €7185 [median €11,925]; IGE: €3599 [median €0], P < 0.001; FE: €5082 [median €2981], P = 0.03) were highest among patients with TSC. The proportion of patients with TSC who were unemployed (60%) was significantly larger than the proportions of patients with IGE (23%, P < 0.001) or FE (34%, P = P < 0.001) who were unemployed. Index scores for the EuroQuol Scale with 5 dimensions and 3 levels were significantly lower for patients with TSC (time-trade-off [TTO]: 0.705, visual analog scale [VAS]: 0.577) than for patients with IGE (TTO: 0.897, VAS: 0.813; P < 0.001) or FE (TTO: 0.879, VAS: 0.769; P < 0.001). Revised Epilepsy Stigma Scale scores were also significantly higher for patients with TSC (3.97) than for patients with IGE (1.48, P < 0.001) or FE (2.45, P < 0.001). Overall Quality of Life in Epilepsy Inventory-31 items scores was significantly lower among patients with TSC (57.7) and FE (57.6) than among patients with IGE (66.6, P = 0.004 in both comparisons). Significant differences between patients with TSC and IGE were also determined for Neurological Disorder Depression Inventory for Epilepsy (TSC: 13.1; IGE: 11.2, P = 0.009) and Liverpool Adverse Events Profile scores (TSC: 42.7; IGE: 37.5, P = 0.017) with higher score and worse results for TSC patients in both questionnaires.

CONCLUSIONS

This study is the first to compare patients with TSC, IGE, and FE in Germany and underlines the excessive QoL burden and both direct and indirect cost burdens experienced by patients with TSC.

Inhibition of p70 Ribosomal S6 Kinase (S6K1) Reduces Cortical Blood Flow in a Rat Model of Autism-Tuberous Sclerosis

The manifestations of tuberous sclerosis complex (TSC) in humans include epilepsy, autism spectrum disorders (ASD) and intellectual disability. Previous studies suggested the linkage of TSC to altered cerebral blood flow and metabolic dysfunction. We previously reported a significant elevation in cerebral blood flow in an animal model of TSC and autism of young Eker rats. Inhibition of the mammalian target of rapamycin (mTOR) by rapamycin could restore normal oxygen consumption and cerebral blood flow. In this study, we investigated whether inhibiting a component of the mTOR signaling pathway, p70 ribosomal S6 kinase (S6K1), would yield comparable effects. Control Long Evans and Eker rats were divided into vehicle and PF-4708671 (S6K1 inhibitor, 75 mg/kg for 1 h) treated groups. Cerebral regional blood flow (14C-iodoantipyrine) was determined in isoflurane anesthetized rats. We found significantly increased basal cortical (+ 32%) and hippocampal (+ 15%) blood flow in the Eker rats. PF-4708671 significantly lowered regional blood flow in the cortex and hippocampus of the Eker rats. PF-4708671 did not significantly lower blood flow in these regions in the control Long Evans rats. Phosphorylation of S6-Ser240/244 and Akt-Ser473 was moderately decreased in Eker rats but only the latter reached statistical significance upon PF-4708671 treatment. Our findings suggest that moderate inhibition of S6K1 with PF-4708671 helps to restore normal cortical blood flow in Eker rats and that this information might have therapeutic potential in tuberous sclerosis complex and autism.

Tuberous sclerosis complex in adulthood: focus on epilepsy prognosis

OBJECTIVE

Typically diagnosed in early childhood or adolescence, TSC is a chronic, multisystemic disorder with age-dependent manifestations posing a challenge for transition and for specific surveillance throughout the lifetime. Data on the clinical features and severity of TSC in adults and on the prognosis of epilepsy are scarce. We analyzed the clinical and genetic features of a cohort of adult patients with TSC, to identify the prognostic predictors of seizure remission after a long follow-up.

METHOD

We conducted a retrospective analysis of patients diagnosed with TSC according to the updated international diagnostic criteria. Pearson's chi-square or Fisher's exact test and Mann Whitney U test were used to compare variables among the Remission (R) and Non-Remission (NR) group. Univariate and multivariate logistic regression analyses were performed.

RESULTS

We selected 43 patients with TSC and neurological involvement in terms of epilepsy and/or brain lesions, attending the Epilepsy Center of our Institute: of them, 16 (37.2%) were transitioning from the pediatric care and 6 (13.9%) were referred by other specialists. Multiorgan involvement includes cutaneous (86.0%), nephrological (70.7%), hepatic (40.0%), ocular (34.3%), pneumological (28.6%) and cardiac (26.3%) manifestations. Thirty-nine patients (90.7 %) had epilepsy. The mean age at seizure onset was 4 ± 7.3 years: most patients (29, 76.3 %) presented with focal seizures or spasms by age 3 years; only 2 (5.3 %) had seizure onset in adulthood. Twenty-seven patients (69.2 %) experienced multiple seizure types overtime, 23 (59.0 %) had intellectual disability (ID). At last assessment, 14 (35.9 %) were seizure free (R group) and 25 (64.1 %) had drug-resistant seizures (NR group). At logistic regression univariate analysis, ID (OR 7.9, 95 % CI 1.8--34.7), multiple seizure types lifelong (OR 13.2, 95 % CI 2.6- 67.2), spasms/tonic seizures at presentation (OR 6.5, 95 % CI 1.2--35.2), a higher seizure frequency at onset (OR 5.4, 95 % CI 1.2--24.3), abnormal neurological examination (OR 9.8, 95 % CI 1.1--90.6) and pathogenic variants in TSC2 (OR 5.4, 95 % CI 1.2--24.5) were significantly associated with non-remission. In the multivariate analysis, both ID and multiple seizure types lifelong were confirmed as independent predictors of poor seizure outcome.

CONCLUSIONS

In our cohort of adult patients with TSC, epilepsy remains one of the main neurological challenges with only 5.3% of cases manifesting in adulthood. Approximately 64% of these patients failed to achieve seizure remission. ID and multiple seizure types were the main predictors of poor outcome. Nephrological manifestations require continuous specific follow-up in adults.

Vigabatrin in Epilepsy Related to TSC: Does it PREVeNT AND OR (EPI) STOP Seizures OR… Do We Need Some More STEPS as VI RAP?

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Astroglial calcium signaling and homeostasis in tuberous sclerosis complex

Tuberous Sclerosis Complex (TSC) is a multisystem genetic disorder characterized by the development of benign tumors in various organs, including the brain, and is often accompanied by epilepsy, neurodevelopmental comorbidities including intellectual disability and autism. A key hallmark of TSC is the hyperactivation of the mechanistic target of rapamycin (mTOR) signaling pathway, which induces alterations in cortical development and metabolic processes in astrocytes, among other cellular functions. These changes could modulate seizure susceptibility, contributing to the progression of epilepsy and its associated comorbidities. Epilepsy is characterized by dysregulation of calcium (Ca2+) channels and intracellular Ca2+ dynamics. These factors contribute to hyperexcitability, disrupted synaptogenesis, and altered synchronization of neuronal networks, all of which contribute to seizure activity. This study investigates the intricate interplay between altered Ca2+ dynamics, mTOR pathway dysregulation, and cellular metabolism in astrocytes. The transcriptional profile of TSC patients revealed significant alterations in pathways associated with cellular respiration, ER and mitochondria, and Ca2+ regulation. TSC astrocytes exhibited lack of responsiveness to various stimuli, compromised oxygen consumption rate and reserve respiratory capacity underscoring their reduced capacity to react to environmental changes or cellular stress. Furthermore, our study revealed significant reduction of store operated calcium entry (SOCE) along with strong decrease of basal mitochondrial Ca2+ concentration and Ca2+ influx in TSC astrocytes. In addition, we observed alteration in mitochondrial membrane potential, characterized by increased depolarization in TSC astrocytes. Lastly, we provide initial evidence of structural abnormalities in mitochondria within TSC patient-derived astrocytes, suggesting a potential link between disrupted Ca2+ signaling and mitochondrial dysfunction. Our findings underscore the complexity of the relationship between Ca2+ signaling, mitochondria dynamics, apoptosis, and mTOR hyperactivation. Further exploration is required to shed light on the pathophysiology of TSC and on TSC associated neuropsychiatric disorders offering further potential avenues for therapeutic development.