TSC-associated Neuropsychiatric Disorders Research Articles

Severe Epilepsy in an Individual With a TSC2 R905Q Variant Prompting Late Diagnosis in Affected Family Members

BackgroundTuberous sclerosis complex (TSC) is a multisystemic disorder caused by inactivating variants in the mTOR pathway inhibitor genes TSC1 and TSC2. Individuals with TSC are predisposed to benign tumors in multiple organs as well as TSC-associated neuropsychiatric disorders (TAND) and epilepsy. Pathogenic variants in TSC2 are typically associated with a more severe phenotype compared with TSC1; the TSC2 R905Q variant has been shown to be an exception, where patients have been reported to present with unusually mild TSC features that may be undetected. MethodsWe studied the TSC phenotype of a 13-year-old individual and three family members with a TSC2 c.2714G>A (R905Q) pathogenic variant. ResultsPatient 1 presented with severe medically refractory epilepsy without tubers or subependymal nodules and only mild dermatologic features of TSC missed on virtual examinations. Her mother and maternal aunt (Patients 2 and 3–diagnosed after age 50 years) presented with a mild phenotype, with dermatologic features and TAND. Her maternal uncle (Patient 4–diagnosed at age 47 years) displayed the most severe phenotype, presenting with intellectual disability, medically refractory epilepsy, obsessive-compulsive disorder, post-traumatic stress disorder, and psychosis. ConclusionsThis study expands the possible phenotypic spectrum of TSC2 R905Q variant, demonstrating an association with severe epilepsy without associated neuroradiological stigmata. This presentation highlights the possibility of occult focal cortical dysplasia in TSC and emphasizes the importance of genetic testing in individuals with severe epilepsy. Moreover, a late adult diagnosis was subsequently made in other family members allowing for appropriate TSC surveillance to occur.

Cortical Gyrification Is Associated With the Clinical Phenotype in Tuberous Sclerosis Complex

BackgroundTuberous sclerosis complex (TSC) is characterized by cortical tubers, determining cortical disarrangement and consequently drug-resistant epilepsy, intellectual disability, and TSC-associated neuropsychiatric disorders (TAND). Aim of the studyTo establish whether gyrification index (GI), a software-based neuroradiological parameter, could be associated with the severity of phenotype in TSC, identifying the cortical regions that are more associated with the severity of the main clinical manifestations. MethodsThis was a retrospective cross-sectional study. Magnetic resonance imaging was acquired on a 1.5-T scanner. CAT12 toolbox was used for the estimation of GI. Data analysis was performed with Jamovi. The level of significance was set to P < 0.05 for all tests. ResultsForty-five patients with TSC and 42 healthy controls were included. Patients with TSC were characterized by higher total GI (P = 0.002) compared with healthy controls. Among patients with TSC, a higher total GI was associated with impaired neurological examination (P = 0.039), epilepsy (P = 0.017), intellectual disability (P = 0.013), TAND (P = 0.013), and higher number of cortical tubers (P < 0.001). An increased local GI in specific cortical areas was associated with TAND and autism spectrum disorders. ConclusionsGI is a software-based neuroradiological parameter that could represent a reliable overall prognostic marker in TSC. Local GI can be used to identify phenotype-specific gyrification patterns allowing an early characterization of patients with TSC.

Enhancing the utility of tuberous sclerosis complex-associated neuropsychiatric disorders checklist in China.

The tuberous sclerosis complex (TSC)-associated neuropsychiatric disorders (TAND) Checklist is a reliable global screening tool for TAND in clinical settings, with six dimensions and 12 sections. For Chinese individuals with TSC, the implementation of the TAND Checklist provides a comprehensive approach to evaluating potential manifestations across various domains.

Review of the spectrum of tuberous sclerosis complex: The Saudi Arabian Experience.

To determine the prevalence of tuberous sclerosis complex (TSC) in the paediatric Saudi population and to characterise the range of clinical symptoms, neurocutaneous findings, neuroimaging results, and complications of the disease. A total of 61 genetically confirmed TSC patients from the National Guard Health Affairs (NGHA) in Saudi Arabia were the subject of this retrospective descriptive analysis. The data were presented using descriptive measures. The mean age at diagnosis was found to be 4.9 years. Subependymal nodules (86.9%), numerous cortical tubers and/or radial migration lines (63.9%), and hypomelanotic macules (63.9%) were the 3 most common significant criteria. The vast majority (86.9%) of those diagnosed had epilepsy, of which 50% were considered medically intractable. Nearly half of our subjects underwent genetic testing, which revealed that TSC2 predominated over TSC1. Symptoms of Tuberous Sclerosis Complex-Associated Neuropsychiatric Disorders (TAND) were present in 66.7% of TSC1 patients and 73.9% of TSC2 patients. The findings of this study demonstrate that the clinical spectrum of TSC among Saudi children is consistent with the body of existing literature. The TSC2 was more prevalent than TSC1. The most frequent signs were cutaneous and neurological. Monitoring TSC patients regularly is crucial to identify any issues as soon as possible.

Neuropsychiatric Manifestations of Tuberous Sclerosis in a young adult male in a Psychiatry Hospital in Botswana: a case report

IntroductionTuberous sclerosis complex (TSC) is a disorder that affects multiple systems and was first described in 1880. Its symptoms include seizures, intellectual disability, and adenoma sebaceum. TSC is caused by mutations in the TSC1 and TSC2 genes and is inherited in an autosomal dominant manner.ObjectivesThis report highlights a case of a patient with an unusual psychological presentation evaluated in a psychiatric hospital.MethodsThe patient presented with psychotic features and abnormal behavior. A physical examination showed neurocutaneous lesions. After assessment a diagnosis of Tuberous sclerosis complex was confirmed through MRI Brain and genetic testing. Some of his relatives also showed similar neuropsychiatric symptoms.ResultsTuberous sclerosis complex is diagnosed based on TSC Clinical Consensus Group guidelines of 2012. Our patient fulfilled 4 of the major criteria and genetic testing also yielded a pathogenic variant. A TAND checklist (TSC-Associated Neuropsychiatric Disorders) is used to guide clinicians on areas to prioritize when managing TSC patients.Image:Image 2:Image 3:ConclusionsGiven that psychiatry may be the first contact for TSC patients, especially in low-resource settings. Patients referred to psychiatry, therefore, need to be thoroughly examined to exclude neuropsychiatric disorders, and a multidisciplinary team approach is vital in investigating and managing these cases.Disclosure of InterestNone Declared

Neuropsychiatric comorbidities in tuberous sclerosis complex patients with epilepsy: results of the TAND checklist survey.

In addition to epilepsy, individuals with tuberous sclerosis complex (TSC) experience a wide range of behavioral, psychiatric, intellectual, academic, and psychosocial problems. They usually exert a large psychological burden on individuals with these illnesses. This cross-sectional study used TSC-associated neuropsychiatric disorders (TAND) checklist interviews conducted at a single medical center. The enrollment of all subjects was > 6years, and the comorbidities of neurodevelopmental disorders were assessed by clinical psychologists before enrollment. To assess the spectrum of TAND, the TAND checklist was applied as stated in the protocol, and the responses to the TAND checklist were evaluated by clinical psychologists. In the behavioral concerns of patients with TSC without epilepsy, those with epilepsy had excessive shyness, language delay, lack of eye contact, rigid behavior, inattentiveness, and restlessness. In psychiatric disorders, autism spectrum disorder and attention-deficit/hyperactivity disorder are significantly correlated with epilepsy history. Diminished academic skills, including reading, writing, and mathematics skills, are significantly associated with epilepsy history. For intellectual ability, TSC patients without epilepsy is associated normal intelligence level. Among neuropsychological skills, deficits in attention, dual tasking/multi-tasking, visuospatial tasking, and executive skills are significantly associated with epilepsy history. Epilepsy in patients with TSC contributes to comorbid neuropsychiatric disorders. In addition to epilepsy evaluation, it is crucial to evaluate the heterogeneous spectrum of neuropsychiatric disorders using a standard checklist during the annual clinical follow-up of patients with TSC.

Patients’ and physicians’ awareness of clinical symptoms and disease severity in tuberous sclerosis complex

Tuberous sclerosis complex (TSC) is a rare inherited disease with the potential to affect virtually every organ system. Clinical presentation is age- and partly sex-dependent and varies broadly with respect to disease manifestations including treatment-refractory epilepsy, intellectual disability and TSC-associated neuropsychiatric disorders, chronic kidney disease or progressive lung function decline. Given the complexity of this disease, multidisciplinary care in specialized TSC centres is recommended. We aimed to elucidate the state of knowledge of patients/caregivers and physicians on individual disease manifestations. We further examined whether the association to a TSC centre has an impact on the comprehensive consideration of potential disease manifestations. Therefore, a survey was performed in a cohort of German TSC patients and their physicians. Complete information was available for 94 patients with a median age of 18 years [range 1–55] and a sex distribution of 53.2% (male): 48.8% (female). Using almost identical questionnaires for patients/caregivers and their respective physician, there was a good correlation for disease assessments associated with relevant morbidity and mortality like epilepsy, renal angiomyolipoma, cardiac rhabdomyomas or intellectual disability. Correlation was moderate for several neuropsychiatric disorders and only poor for hypomelanotic macules, dental pits or retinal achromic patches. Estimation of overall disease severity using a numeric rating scale correlated highly significantly (Pearson correlation coefficient = 0.767; p < 0.001) between patients/caregivers and physicians. In general, physicians more likely quoted items as ‘unknown’ than patients (822 answers vs. 435 answers in the respective groups). Questionnaires completed by physicians who were associated with a specialized TSC centre declared a significantly lower proportion of items as unknown (mean 8.7% vs. 20.5%; p < 0.001). These findings indicate that patients treated by specialized TSC centres seem to obtain a more comprehensive surveillance. Furthermore, it shows that there were reasonable surveillance strategies in general and sufficient patient/caregiver interaction and education in the examined cohort. However, for the most prominent disease characteristics there was a good awareness within both the patients/caregivers and the physicians group.

A Cost-Utility Analysis of Add-On Cannabidiol Versus Usual Care Alone for the Treatment of Seizures Associated with Tuberous Sclerosis Complex in England and Wales.

The aim of this study was to evaluate the cost effectiveness of plant-derived highly purified cannabidiol (Epidyolex® in the UK; 100mg/mL oral solution) as an add-on treatment to usual care for the management of treatment-refractory seizures associated with tuberous sclerosis complex (TSC) in patients aged ≥2 years. A cohort-based model was developed using a National Health Service perspective and lifetime horizon. Health states were based on weekly seizure frequency and seizure-free days, utilizing patient-level data from the GWPCARE6 trial (ClinicalTrials.gov identifier: NCT02544763). Two independent regression models were applied to individual patient-level data to predict seizure-free days and seizure frequency. Healthcare resource utilization data were sourced from a Delphi panel, and patient and caregiver health-related quality of life values were elicited using vignettes valued by the general public. Outcomes relating to TSC-associated neuropsychiatric disorders were modeled with costs and quality-adjusted life-years sourced from published literature. In the base case, compared with usual care alone, 12mg/kg/day cannabidiol was associated with an incremental cost-effectiveness ratio (ICER) of £23,797. The National Institute for Health and Care Excellence disease severity modifier reduced the ICER to £19,831. Probabilities of cost effectiveness at willingness-to-pay thresholds of £20,000 and £30,000 were 30% and 52%, respectively, for the base case and 39% and 66%, respectively, for the disease severity modifier. Results were robust to sensitivity and scenario analyses. At 12mg/kg/day and an ICER threshold of £20,000-£30,000, we provide evidence for the cost effectiveness of add-on cannabidiol treatment for patients with TSC-associated seizures aged ≥2 years who are refractory to current treatment.

The role of the TSC Alliance in advancing therapy development: a patient organization perspective.

Tuberous sclerosis complex (TSC) is a genetic disease leading to malformations, or tubers, in the cerebral cortex and growth of tumors, most frequently in the brain, heart, kidneys, skin, and lungs. Changes in the brain caused by TSC usually have the biggest negative impact on quality of life. Approximately 85% of individuals with TSC have epilepsy, and TSC-associated neuropsychiatric disorders (TAND) affect nearly all individuals with TSC in some way. TSC Alliance's research strategy is built upon both funding and catalyzing research. Through grants, the organization provides funding directly to researchers through a competitive application process. The organization has also built a set of resources available to researchers worldwide, including a Natural History Database, Biosample Repository, and Preclinical Consortium. These resources catalyze research because they are available to qualified academic or industry researchers around the world, enabling an almost unlimited number of scientists to access data and resources to enable and accelerate research on TSC. This research strategy continues to be shaped by the needs and priorities of the TSC community, working toward a future where everyone affected by TSC can live their fullest lives.

Bibliometric analysis and network visualization on Tuberous Sclerosis Complex

Background: Tuberous sclerosis complex (TSC) is a rare autosomal dominant multisystem disease resulting from hyperactivation of the mammalian target of rapamycin (mTOR) signaling pathway. This study aimed to measure the quantitative impact of publications in TSC.&#x0D; Materials and methods: We analysed TSC literature obtained from the Scopus database using Bibliometrix R Package and VOSviewer software. Annual publication trends, most productive and collaborative authors/institutions/ countries, most cited articles, most popular journals and author’s keywords were presented using standard bibliometric indicators.&#x0D; Results and discussion: A total of 5375 documents on TSC were published from 1960 to December 2020, with an increasing trend. The three primary contributing writers were Curatolo P, Kwiatkowski DJ, and Thiele EA, with the United States and its institutions being the largest contributor. The research identified two of the most referenced papers as TSC’s seminal pieces. The top journals that published TSC research were medical journals, namely Journal of Child Neurology, Epilepsia, and Pediatric Neurology. mTOR inhibitor, everolimus, sirolimus, mTORC1, mTOR pathway, autophagy, inflammation, infant, intellectual disability, white matter, TSC-associated neuropsychiatric disorders, TOSCA and quality of life were relatively newer author’s keywords and may indicate the future research hotspots in TSC research.&#x0D; Conclusion: Over the last few decades, TSC research has grown in importance, particularly in the field of clinical medicine. Therapeutic components targeting TSC-related pathways, the utilisation of TSC as disease models and long-term safety studies will be future research areas.&#x0D; Bangladesh Journal of Medical Science Vol. 23 No. 01 January’24 Page : 18-28

Translatome analysis of tuberous sclerosis complex 1 patient-derived neural progenitor cells reveals rapamycin-dependent and independent alterations

BackgroundTuberous sclerosis complex (TSC) is an inherited neurocutaneous disorder caused by mutations in the TSC1 or TSC2 genes, with patients often exhibiting neurodevelopmental (ND) manifestations termed TSC-associated neuropsychiatric disorders (TAND) including autism spectrum disorder (ASD) and intellectual disability. Hamartin (TSC1) and tuberin (TSC2) proteins form a complex inhibiting mechanistic target of rapamycin complex 1 (mTORC1) signaling. Loss of TSC1 or TSC2 activates mTORC1 that, among several targets, controls protein synthesis by inhibiting translational repressor eIF4E-binding proteins. Using TSC1 patient-derived neural progenitor cells (NPCs), we recently reported early ND phenotypic changes, including increased cell proliferation and altered neurite outgrowth in TSC1-null NPCs, which were unaffected by the mTORC1 inhibitor rapamycin.MethodsHere, we used polysome profiling, which quantifies changes in mRNA abundance and translational efficiencies at a transcriptome-wide level, to compare CRISPR-edited TSC1-null with CRISPR-corrected TSC1-WT NPCs generated from one TSC donor (one clone/genotype). To assess the relevance of identified gene expression alterations, we performed polysome profiling in postmortem brains from ASD donors and age-matched controls. We further compared effects on translation of a subset of transcripts and rescue of early ND phenotypes in NPCs following inhibition of mTORC1 using the allosteric inhibitor rapamycin versus a third-generation bi-steric, mTORC1-selective inhibitor RMC-6272.ResultsPolysome profiling of NPCs revealed numerous TSC1-associated alterations in mRNA translation that were largely recapitulated in human ASD brains. Moreover, although rapamycin treatment partially reversed the TSC1-associated alterations in mRNA translation, most genes related to neural activity/synaptic regulation or ASD were rapamycin-insensitive. In contrast, treatment with RMC-6272 inhibited rapamycin-insensitive translation and reversed TSC1-associated early ND phenotypes including proliferation and neurite outgrowth that were unaffected by rapamycin.ConclusionsOur work reveals ample mRNA translation alterations in TSC1 patient-derived NPCs that recapitulate mRNA translation in ASD brain samples. Further, suppression of TSC1-associated but rapamycin-insensitive translation and ND phenotypes by RMC-6272 unveils potential implications for more efficient targeting of mTORC1 as a superior treatment strategy for TAND.

International consensus recommendations for the identification and treatment of tuberous sclerosis complex-associated neuropsychiatric disorders (TAND)

BackgroundTuberous sclerosis complex (TSC) is associated with a wide range of physical manifestations for which international clinical recommendations for diagnosis and management have been established. TSC is, however, also associated with a wide range of TSC-Associated Neuropsychiatric Disorders (TAND) that are typically under-identified and under-treated yet associated with a profound burden of disease. The contemporary evidence base for the identification and treatment of TAND is much more limited and, to date, consensus recommendations for the diagnosis and management of TAND have also been limited and non-specific.MethodsThe TANDem project was launched with an international, interdisciplinary, and participatory consortium of 24 individuals, including TSC family representatives, from all World Health Organization (WHO) regions but one. One of the aims of the TANDem project was to generate consensus recommendations for the identification and treatment of TAND. At the time of this project, no internationally adopted standard methodology and methodological checklists existed for the generation of clinical practice recommendations. We therefore developed our own systematic procedure for evidence review and consensus-building to generate evidence-informed consensus recommendations of relevance to the global TSC community.ResultsAt the heart of the consensus recommendations are ten core principles surrounded by cluster-specific recommendations for each of the seven natural TAND clusters identified in the literature (autism-like, dysregulated behavior, eat/sleep, mood/anxiety, neuropsychological, overactive/impulsive, and scholastic) and a set of wraparound psychosocial cluster recommendations. The overarching recommendation is to “screen” for TAND at least annually, to “act” using appropriate next steps for evaluation and treatment, and to “repeat” the process to ensure early identification and early intervention with the most appropriate biological, psychological, and social evidence-informed approaches to support individuals with TSC and their families.ConclusionsThe consensus recommendations should provide a systematic framework to approach the identification and treatment of TAND for health, educational, social care teams and families who live with TSC. To ensure global dissemination and implementation of these recommendations, partnerships with the international TSC community will be important. One of these steps will include the generation of a “TAND toolkit” of “what to seek” and “what to do” when difficulties are identified in TAND clusters.

Tuberous sclerosis complex-associated neuropsychiatric disorders.

The aim of the study was to provide a state-of-the-art review with regard to neuropsychiatric disorders associated with tuberous sclerosis complex (TSC). TSC is a rare genetic disease classified as a phacomatosis. Due to the wide spectrum of clinical symptoms of the disease, many cases remain undiagnosed. The vast majority of people with a mutation in the TSC1 or TSC2 genes develop some of the neuropsychiatric symptoms during their lifetime. Diagnostic criteria, neuroanatomical pathology and pathophysiology of psychiatric, neuropsychological, developmental and psychosocial symptoms present in TSC are described. The specificity of epilepsy in TSC and its role in neuropsychiatric and neuropsychological development are presented. All levels (intellectual, developmental, behavioral, psychiatric, school, neuropsychological and psychosocial) of tuberous sclerosis complex-associated neuropsychiatric disorders (TAND) are discussed in detail. The TAND Checklist - a tool for assessing all potentially disturbed aspects of functioning - was presented. The importance of proper diagnosis of neuropsychiatric disorders and multidisciplinary patient care was emphasized.

Development and Feasibility of the Self-Report Quantified Tuberous Sclerosis Complex-Associated Neuropsychiatric Disorders Checklist (TAND-SQ)

BackgroundTuberous sclerosis complex-associated neuropsychiatric disorders (TAND) are often present but underidentified and undertreated in individuals with tuberous sclerosis complex (TSC). The clinician-completed TAND-Lifetime Checklist (TAND-L) was developed to address this identification and treatment gap. Stakeholder engagement identified the need for a TAND Checklist that can (1) be completed by caregivers or individuals with TSC and (2) quantify TAND difficulties. The aim of this study was to develop a self-report quantified TAND Checklist (TAND-SQ) and conduct feasibility and acceptability testing. MethodsThis aim was addressed in three phases: (1) development of the TAND-SQ Checklist, (2) feasibility and acceptability testing of the “near-final” TAND-SQ Checklist, and (3) preparation of the final TAND-SQ Checklist. Participants included 23 technical experts from the TAND consortium in all phases and 58 lived experts (caregivers and individuals with TSC) in phase 2. All participants completed a TAND-SQ Checklist and a checklist feedback form. ResultsPhase 1 additions to the TAND-SQ, when compared with the TAND-L, included four new items and a quantification rating. Phase 2 showed high ratings for the “near-final” TAND-SQ Checklist on comprehensiveness, clarity, ease of use, and overall acceptability. In phase 3, questions on strengths, strategies, and a TAND Cluster Profile were added. ConclusionThe TAND-SQ Checklist is presented here for use by individuals with TSC and their caregivers. The next steps as part of the TANDem project include internal and external validation of the checklist and linking of TAND Cluster Profiles generated from the checklist to evidence-informed consensus recommendations within a smartphone application.

De novo mutation of the TSC2 gene in patient with Tuberous Sclerosis Complex-Associated Neuropsychiatric Disorders (TAND) Phenotype: a case report.

A 17-year-old girl presented with TSC, absence and focal epilepsy, borderline intellectual functioning, organic psychosis, and renal angiomyolipoma. She was emotionally unstable and preoccupied with irrelevant fears. In the physical examination, we found multiple hypomelanotic maculae, angiofibroma, and a shagreen patch. The intellectual assessment result with the Wechsler Adult Intelligence Scale at 17 was borderline intellectual functioning. Brain MRI showed cortical and subcortical tubers in the parietal and occipital lobes. Whole-exome sequencing was conducted, and the result was a missense mutation in exon 39 of the TSC2 gene [NM_000548.5:c.5024C>T (NP_000539.2:p.Pro1675Leu)]. The Sanger sequencing of the patient's parents revealed no mutations in the TSC2 gene, confirming the patient's de novo mutation. The patient was given several antiepileptic and antipsychotic drugs. Neuropsychiatric manifestation is a common phenotype in the TSC variant, and psychosis is one of the rare TAND symptoms in children. The neuropsychiatric phenotype and genotype in TSC patients are rarely reported and evaluated. We reported a female child with epilepsy, borderline intellectual functioning, and organic psychosis associated with a de novo mutation of the TSC2 gene. Organic psychosis is a rare symptom of TAND which also manifested in our patient.

Tuberous Sclerosis Complex.

Tuberous sclerosis complex (TSC) is an autosomal dominant inherited disease characterized by systemic hamartomas, neuropsychiatric symptoms known as TAND (TSC-associated neuropsychiatric disorders), and vitiligo. These symptoms are attributed to the constant activation of mechanistic target of rapamycin complex 1 (mTORC1) caused by genetic mutations in the causative genes TSC1 or TSC2. The elucidation of the pathogenesis of this disease and advances in diagnostic technologies have led to dramatic changes in the diagnosis and treatment of TSC. Diagnostic criteria have been created at a global level, and mTORC1 inhibitors have emerged as therapeutic agents for this disease. Previously, the treatment strategy was limited to symptomatic treatments such as surgery. Inhibitors of mTORC1 are effective against all symptoms of TSC, but they also have systemic side effects. Therefore, the need for a cross-disciplinary, collaborative medical care system has increased, resulting in the establishment of a practice structure known as the "TSC Board." Furthermore, to reduce the side effects of systemic administration of mTORC1 inhibitors, a topical formulation of mTORC1 inhibitor was developed in Japan for the treatment of skin lesions caused by TSC. This report summarizes the pathogenesis and current status of TSC and the contribution of the Neurocutaneous Syndrome Policy Research Group to the policies of the Ministry of Health, Labor, and Welfare with respect to this rare, intractable disease.

Tuberous Sclerosis Complex Patients' Needs and Difficulties-Results of TAND Questionnaire Analysis in Polish Adult Population.

Tuberous Sclerosis Complex (TSC) is a rare genetic disease. Around 90% of individuals with TSC present some neuropsychiatric manifestations (TSC-associated neuropsychiatric disorders, TAND). To date, none of the studies have focused on the TAND profile of the adult population. Thus, the aim of the study was to describe their potential specific needs and difficulties, including differences in cohorts with or without epilepsy and/or intellectual disability. The Polish version of the TAND Checklist was used for assessment of individuals with TSC. Participants had to meet the criteria for diagnosis of TSC. One hundred adult participants (forty-eight males/ fifty-two females; mean age 32.33 ± 11.29) were enrolled in the study. Epilepsy was present in 71% of patients; intellectual disability occurred in a total of 37%. Only 11% of individuals received complete TAND features examination in the past. Moreover, 91.5 of the subjects had four and more TAND symptoms. Intellectually disabled patients and those with epilepsy had more neuropsychiatric problems than epilepsy-free subjects. Findings reveal that TANDs are common in adults with TSC and are underdiagnosed. Most individuals present several behavioural and cognitive problems. Among psychiatric disorders, the most common are ASD, depression, and anxiety disorder. TAND screening should be widely disseminated and applied in clinical practice for early identification, prevention, and rehabilitation of their difficulties. TAND is one of the most significant issues affecting the quality of life of TSC patients and their carers.

Clinical profile of tuberous sclerosis complex patients with and without epilepsy: a need for awareness for early diagnosis.

Tuberous sclerosis complex (TSC) is a multisystemic disorder. Its clinical features manifest differently in several organs, prompting the need for better knowledge. The goal of the present study is to evaluate the neurological findings of TSC, such as cerebral lesions and epilepsy, and to raise awareness of non-neurological findings that could contribute to an earlier diagnosis and treatment. This was a natural history study of patients with a definitive diagnosis of TSC who were referred to a specialized outpatient clinic and followed-up for 2 years with clinical and radiological exams. A total of 130 TSC patients (59 males [45.4%], mean age 20.4 years old [1 to 56 years old]); 107 patients (82.3%) were diagnosed with epilepsy. Seizures predominantly began at < 1 year old (72.8%); focal seizures predominated (86.9%); epileptic spasms occurred in 34.5% of patients, and refractory epilepsy was present in 55.1%. Neuropsychiatric disorders, cortical tubers and cerebellar tubers were significantly more frequent in the epilepsy group. Moreover, rhabdomyomas were significantly more frequent in the epilepsy group (p = 0.044), while lymphangioleiomyomatosis was significantly less frequent in the epilepsy group (p = 0.009). Other non-neurological findings did not differ significantly between the groups with and without epilepsy. The present study of TSC patients demonstrated the predominantly neurological involvement and significantly higher proportion of TSC-associated neuropsychiatric disorders in the epilepsy group. Higher proportions of cortical and cerebellar tubers may be a risk factor for epilepsy and neurodevelopmental disorders.

Sirolimus relieves seizures and neuropsychiatric symptoms via changes of microglial polarity in tuberous sclerosis complex model mice

Tuberous sclerosis complex (TSC) is a genetic disorder involving a variety of physical manifestations, and is associated with epilepsy and multiple serious neuropsychiatric symptoms. These symptoms are collectively known as TSC-associated neuropsychiatric disorders (TAND), which is a severe burden for patients and their families. Overactivation of the mechanistic target of rapamycin complex 1 (mTORC1) by mutations in TSC1 or TSC2 is thought to cause TSC, and mTORC1 inhibitors such as sirolimus and everolimus are reported to be effective against various tumor types of TSC. However, there are various reports on the effect of mTORC1 inhibitor therapy on TAND in patients with TSC, which may or may not be effective. In our previous investigations, we generated TSC2 conditional knockout mice (Mitf-Cre, Tsc2 KO; Tsc2 cKO). These mice developed spontaneous epileptic activity. In the current study, we further analyzed the detailed behaviors of Tsc2 cKO mice and confirmed that they exhibited phenotypes of TAND as well as epileptic seizures, indicating that Tsc2 cKO mice are a useful model for TAND. Furthermore, the olfactory bulb and piriform cortex caused epilepsy and TAND in Tsc2 cKO mice, and neurodegeneration was observed. Immunohistology and immunophenotypic analysis of cells, and quantitative RT-PCR suggested that changes in microglial polarity were involved in the onset of TSC epilepsy and neuropsychiatric symptoms. Although the effect of mTORC1 inhibitors on TAND has not been established, the results of this study might help elucidate the mechanism of TAND pathogenesis and suggest that sirolimus may be a valuable therapeutic tool for TAND.

Modeling tuberous sclerosis complex with human induced pluripotent stem cells.

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder with a birth incidence of 1:6000 in the United States that is characterized by the growth of non-cancerous tumors in multiple organ systems including the brain, kidneys, lungs, and skin. Importantly, TSC is also associated with significant neurological manifestations including epilepsy, TSC-associated neuropsychiatric disorders, intellectual disabilities, and autism spectrum disorder. Mutations in the TSC1 or TSC2 genes are well-established causes of TSC, which lead to TSC1/TSC2 deficiency in organs and hyper-activation of the mammalian target of rapamycin signaling pathway. Animal models have been widely used to study the effect of TSC1/2 genes on the development and function of the brain. Despite considerable progress in understanding the molecular mechanisms underlying TSC in animal models, a human-specific model is urgently needed to investigate the effects of TSC1/2 mutations that are unique to human neurodevelopment. Literature reviews and research articles were published in PubMed-indexed journals. Human-induced pluripotent stem cells (iPSCs), which capture risk alleles that are identical to their donors and have the capacity to differentiate into virtually any cell type in the human body, pave the way for the empirical study of previously inaccessible biological systems such as the developing human brain. In this review, we present an overview of the recent progress in modeling TSC with human iPSC models, the existing limitations, and potential directions for future research.