Approaching psychology's current crises by exploring the vagueness of psychological concepts: Recommendations for advancing the discipline.

Psychology is currently facing a multilayered crisis stemming from the fact that the results of many psychological studies cannot be replicated (replication crisis), that psychological research has neglected cross-cultural and cross-temporal variation (universality crisis), and that many psychological theories are ill-developed and underspecified (theory crisis). In the present article, we use ideas derived from debates in theoretical and philosophical psychology as a basis for responding to all three crises. In short, we claim that psychological concepts are inherently vague in the sense that their meanings and the rules for their application are indeterminate. This does not imply that psychological concepts are ineffable or lack meaning. It implies, however, that hoping to arrive at a finite set of necessary and sufficient criteria that define psychological concepts once and for all is an illusion. From this, we deduce four recommendations for responding to psychology's crises. First, we argue that the replication crisis could be approached by paying more attention to the context conditions under which psychological realities and knowledge about these realities are being created. Second, we claim that the universality crisis can be alleviated by putting more effort into exploring variability across times and cultures. Third, we contend that acknowledging the language dependence of psychological research could be a fruitful way of addressing the theory crisis. Last, we show that embracing theoretical and methodological pluralism would be an antidote against psychology's crises in general. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Stiripentol for Drug-Resistant Epilepsy Treatment in Tuberous Sclerosis Complex.

BACKGROUND: Drug-resistant epilepsy (DRE) is common in tuberous sclerosis complex (TSC). The role of stiripentol (STP) in seizure treatment in this population is not well understood. This study evaluates the efficacy and tolerability of STP in patients with TSC with DRE. METHODS: We performed a retrospective review of patients with TSC with DRE. Seizure frequencies at 1 month before (baseline) and 1, 3, 6, and 12 months after STP initiation were collected. RESULTS: Of the 1492 patients, 13 received STP and the number of patients with ≥50% seizure reduction at 1, 3, 6, and 12 months was 6/13 (46.2%), 4/13 (30.8%), 8/13 (61.5%), and 6/13 (46.2%), respectively. Six patients (46.2%) had favorable outcomes with persistent seizure reduction through 12 months. Their mean (±S.D.) percentage of seizure reduction at 1, 3, 6, and 12 months was 68.1 (±22.0), 71.3 (±23.2), 75.7 (±23.5), and 75.7 (±23.5), respectively. One patient had worsening seizures throughout the STP course. Three patients did not have seizure reduction until after 6 months, and 2 had initial seizure reduction before worsening. Younger age (P value <0.001), early STP treatment (P value <0.001), higher doses (P value = 0.004), and higher baseline seizure frequency (P value = 0.01) were associated with favorable outcomes. Side effects were seen in 85% of our cohort. CONCLUSIONS: About 46% of the patients had favorable outcomes. Younger age, early STP treatment, higher doses, and higher baseline seizure frequency were significantly associated with favorable outcomes.

Cellular and molecular characterization of two novel asparagine synthetase gene mutations linked to asparagine synthetase deficiency.

Asparagine synthetase (ASNS) catalyzes synthesis of asparagine (Asn) and Glu from Asp and Gln in an ATP-dependent reaction. Asparagine synthetase deficiency (ASNSD) results from biallelic mutations in the ASNS gene. Affected children exhibit congenital microcephaly, continued brain atrophy, seizures, and often premature mortality. However, the underlying mechanisms are unclear. This report describes a compound heterozygotic ASNSD child with two novel mutations in the ASNS gene, c.1118G>T (paternal) and c.1556G>A (maternal), that lead to G373V or R519H ASNS variants. Structural mapping suggested that neither variant participates directly in catalysis. Growth of cultured fibroblasts from either parent was unaffected in Asn-free medium, whereas growth of the child's cells was suppressed by about 50%. Analysis of Asn levels unexpectedly revealed that extracellular rather than intracellular Asn correlated with the reduced proliferation during incubation of the child's cells in Asn-free medium. Our attempts to ectopically express the G373V variant in either HEK293T or JRS cells resulted in minimal protein production, suggesting instability. Protein expression and purification from HEK293T cells revealed reduced activity for the R519H variant relative to WT ASNS. Expression of WT ASNS in ASNS-null JRS cells resulted in nearly complete rescue of growth in Asn-free medium, whereas we observed no proliferation for the cells expressing either the G373V or R519H variant. These results support the conclusion that the coexpression of the G373V and R519H ASNS variants leads to significantly reduced Asn synthesis, which negatively impacts cellular growth. These observations are consistent with the ASNSD phenotype.

Prevalence of thoracoabdominal imaging findings in tuberous sclerosis complex.

BACKGROUND: Tuberous sclerosis complex (TSC) results in neurodevelopmental phenotypes, benign tumors, and cysts throughout the body. Recent studies show numerous rare findings in TSC. Guidelines suggest routine abdominal and chest imaging to monitor these thoracoabdominal findings, but imaging is not uniformly done across centers. Thus, the prevalence of many findings is unknown. To answer this, we categorized the clinical reads of 1398 thoracoabdominal scans from 649 patients of all ages in the Cincinnati Children's Hospital TSC Repository Database. RESULTS: Typical TSC findings were present in many patients: kidney cysts (72%), kidney fat-containing angiomyolipomas (51%), kidney lipid-poor angiomyolipomas (27%), liver angiomyolipomas (19%), and lung nodules thought to represent multifocal micronodular pneumocyte hyperplasia (MMPH) (18%). While many features were more common in TSC2 patients, TSC1 patients had a higher prevalence of MMPH than TSC2 patients (24% versus 13%, p = 0.05). Many rare findings (e.g., lymphatic malformations and liver masses) are more common in TSC than in the general population. Additionally, most thoracoabdominal imaging findings increased with age except kidney cysts which decreased, with the 0-10 years age group having the highest percentage (69% 0-10 years, 49% 10-21 years, 48% 21 + years, p < 0.001). Finally, in our population, no patients had renal cell carcinoma found on abdominal imaging. CONCLUSIONS: These results show that regular thoracoabdominal scans in TSC may show several findings that should not be ignored or, conversely, over-reacted to when found in patients with TSC. Female sex, TSC2 mutation, and age are risk factors for many thoracoabdominal findings. The data suggest novel interactions of genetic mutation with pulmonary nodules and age with renal cysts. Finally, in agreement with other works, these findings indicate that several rare thoracoabdominal imaging findings occur at higher rates in the TSC population than in the general population. This work supports obtaining detailed thoracoabdominal imaging in patients with TSC.

Symptom rates and profile clustering in tuberous sclerosis complex-associated neuropsychiatric disorders (TAND).

BACKGROUND: Tuberous Sclerosis Complex (TSC) is associated with a range of neuropsychiatric difficulties, appropriately termed TSC-Associated Neuropsychiatric Disorders (TAND). The objectives of the study were to analyze the rates of TAND symptoms in a cohort of patients seen at the TSC Center of Excellence at Cincinnati Children's Hospital and to identify clinically meaningful profiles based on TAND symptoms. METHODS: Data from the TAND Checklist was obtained from participants seen at the TSC Center of Excellence at Cincinnati Children's Hospital Medical Center from June 2015 to August 2018. Cluster and factor analyses for each TAND symptom were performed. Factor scores were then calculated for participants, and a K-means cluster analysis of these scores was used to empirically identify distinct overall TAND symptom profiles occurring in TSC. RESULTS: A total of 1545 checklists was completed for 668 participants (37% adults and 63% children). Approximately 90% of participants reported at least one TAND symptom with an average of 12 symptoms (out of 29). Symptom rates ranged between 5 and 60%. The most common symptoms were neuropsychologic symptoms. A seven-cluster and seven-factor solution were found to be optimal. K-means cluster analysis resulted in a seven-profile solution, ranging from low to high symptom burden. CONCLUSION: This study is the first to identify natural phenotypic profiles of TAND symptoms. Study of specific TAND subpopulations with shared profiles may facilitate better understanding of the underlying biology of TAND and better assessment of more targeted treatments.

Adjunctive everolimus therapy for tuberous sclerosis complex-associated refractory seizures: Results from the postextension phase of EXIST-3.

OBJECTIVE: Epilepsy is highly prevalent in patients with tuberous sclerosis complex (TSC). Everolimus showed higher efficacy than placebo for seizures in the primary analysis of the EXIST-3 study. Here, we present the long-term outcomes of everolimus at the end of the postextension phase (PEP; data cutoff date: October 25, 2017). METHODS: After completion of the extension phase, patients were invited to continue everolimus in the PEP with everolimus (targeted trough concentration = 5-15 ng/ml, investigator-judged). Efficacy assessments included changes in seizure status during the PEP collected at 12-week intervals as parent/caregiver-reported data through a structured questionnaire. RESULTS: Among 361 patients, 343 entered the extension phase and 249 entered the PEP. After 12 weeks in the PEP, 18.9% (46/244) of patients were seizure-free since the last visit of the extension phase and 64.8% (158/244) had a stable/improved seizure status. At 24 weeks, the corresponding percentages were 18.2% (42/231) and 64.5% (149/231). Among 244 patients, the response rate was 32.8% (80/244) during the 12-week maintenance period of the core phase and 63.9% (156/244) at the end of the extension phase. Of the 149 responders at the end of the extension phase, 70.5% were seizure-free or had stable/improved seizure status. Long-term efficacy data showed persistent responses were observed in 183 of 361 patients (50.7%); 63.9% of these patients had a response that lasted at least 48 weeks. The most frequent Grade 3-4 adverse events (≥2% incidence) reported throughout the study were pneumonia, status epilepticus, seizure, stomatitis, neutropenia, and gastroenteritis. Four patients died during the study. SIGNIFICANCE: The final analysis of EXIST-3 demonstrated the sustained efficacy of everolimus as adjunctive therapy in patients with TSC-associated treatment-refractory seizures, with a tolerable safety profile.

Technology Advances, High-Risk Research, and a Safe Way Forward.

The human and economic toll of the coronavirus disease 2019 (COVID-19) pandemic and the unknowns regarding the origins of the virus, with a backdrop of enormous advances in technologies and human understanding of molecular virology, have raised global concerns about the safety of the legitimate infectious disease research enterprise. We acknowledge the safety and security risks resulting from the broad availability of tools and knowledge, tools and knowledge that can be exploited equally for good or harm. The last 2 decades have shown us that the risks are real. They have also shown us that more traditional top-down regulations alone are not the answer. We encourage government to be thoughtful and nuanced in dealing with this significant challenge and to carefully consider human factors and the important role of organizational-level leadership before simply layering an additional bureaucratic burden on the enterprise without understanding value and cost.

Prenatal Sirolimus Treatment for Rhabdomyomas in Tuberous Sclerosis.

BACKGROUND: In tuberous sclerosis, most cardiac rhabdomyomas regress spontaneously. In some cases, the tumors can cause life-threatening hemodynamic compromise requiring subsequent surgical resection. The mechanistic target of rapamycin inhibitors everolimus and sirolimus have shown to be effective treatments for multiple conditions. There are four reports of off-label treatment with transplacental sirolimus for fetal rhabdomyomas due to tuberous sclerosis complex. The optimal dosing regimen is unknown. METHODS: We reviewed the medical records of all patients treated prenatally with sirolimus for rhabdomyomas. All fetuses had a clinical and molecular diagnosis of tuberous sclerosis complex (2012 Consensus Diagnostic Criteria, including a positive genetic test). Clinical history, mechanistic target of rapamycin inhibitor dosing and levels, outcome, and adverse events were reviewed after initiation of sirolimus treatment. RESULTS: Three fetuses were treated with maternal sirolimus. Dosing regimens and subsequent trough levels differed from 1 mg/day to 6 mg/day and <1.0 ng/mL to 12.2 ng/mL. Cardiac rhabdomyomas gradually shrank in all patients. Growth restriction was noted in one patient. No severe adverse events occurred during the treatment period. CONCLUSIONS: Maternal sirolimus appears to be a safe treatment option in prenatally detected rhabdomyomas with possible need for intervention. Follow-up visits with fetal ultrasound, echocardiography, and laboratory work should be performed weekly during the treatment period. The optimal dosing and trough level timepoints remain unclear. Based on our results, we recommend a sirolimus starting dose of at least 2 mg/m2/day, preferably 3-3.5 mg/m2/day to achieve a target trough level of 10-12 ng/mL.

Diabetes in Individuals With Tuberous Sclerosis Complex Treated With mTOR Inhibitors.

BACKGROUND: Tuberous sclerosis complex (TSC) is a genetic disorder that is manifested in multiple body systems. A mammalian target of rapamycin (mTOR) inhibitor (mTORi), either everolimus or sirolimus, is now routinely prescribed for multiple clinical manifestations of TSC, including subependymal giant cell astrocytoma and epilepsy. These medications are generally well tolerated. Side effects previously identified in well-designed clinical trials tend to be mild and readily manageable. Regulatory approvals for the treatment of TSC have expanded the use of everolimus and sirolimus clinically, enlarging clinician experience and enabling identification of potential treatment-related effects that are rarer than could be identified or recognized in previous clinical trials. METHODS: The medical records of clinical patients from our TSC center who were treated with an mTORi and later developed diabetes mellitus (DM) were analyzed and compared with those who were not treated with an mTORi. Eight individuals received detailed analysis, including laboratory results, concomitant medications, and body mass indices. RESULTS: Among the 1576 individuals with TSC, 4% taking an mTORi developed diabetes compared with 0.6% of those not on mTORi, showing a significant interaction between DM and mTORi (chi-square = 18.1, P < 0.001). Details of eight patients who developed DM were presented. CONCLUSIONS: The long-term use of mTORi agents in TSC may contribute to a risk of diabetes. Early detection can be critical in management. Additional studies are need to further investigate a causal relationship, but clinicians should be aware of this possible association when initiating and monitoring ongoing treatment.

RHOA signaling defects result in impaired axon guidance in iPSC-derived neurons from patients with tuberous sclerosis complex.

Patients with Tuberous Sclerosis Complex (TSC) show aberrant wiring of neuronal connections formed during development which may contribute to symptoms of TSC, such as intellectual disabilities, autism, and epilepsy. Yet models examining the molecular basis for axonal guidance defects in developing human neurons have not been developed. Here, we generate human induced pluripotent stem cell (hiPSC) lines from a patient with TSC and genetically engineer counterparts and isogenic controls. By differentiating hiPSCs, we show that control neurons respond to canonical guidance cues as predicted. Conversely, neurons with heterozygous loss of TSC2 exhibit reduced responses to several repulsive cues and defective axon guidance. While TSC2 is a known key negative regulator of MTOR-dependent protein synthesis, we find that TSC2 signaled through MTOR-independent RHOA in growth cones. Our results suggest that neural network connectivity defects in patients with TSC may result from defects in RHOA-mediated regulation of cytoskeletal dynamics during neuronal development.

Frequency, Progression, and Current Management: Report of 16 New Cases of Nonfunctional Pancreatic Neuroendocrine Tumors in Tuberous Sclerosis Complex and Comparison With Previous Reports.

Background: Tuberous sclerosis complex (TSC) is a genetic condition that causes benign tumors to grow in multiple organ systems. Nonfunctional pancreatic neuroendocrine tumors (PNETs) are a rare clinical feature of TSC with no specific guidelines outlined for clinical management at this time. Our purpose is to calculate the frequency of nonfunctional PNETs as well as characterize the presentation, current clinical management, and assess the impact of systemic mammalian target of rapamycin (mTOR) on nonfunctional PNETs in TSC. Methods: This retrospective chart review was performed by a query of the TS Alliance's Natural History Database and the Cincinnati Children's Hospital TSC Database for patients with nonfunctional PNET. Clinical data from these two groups was summarized for patients identified to have a nonfunctional PNET and compared to previously reported cases with TSC and nonfunctional PNETs. Results: Our calculated frequency of nonfunctional PNETs is 0.65%. We identified 16 individuals, nine males and seven females, with a median age of 18.0 years (interquartile range: -15.5 to 25.5). Just over half (56.3%, n = 9) of the patients provided results from genetic testing. Six had pathogenic variants in TSC2 whereas three had pathogenic variants in TSC1. The average age at PNET diagnosis was 15.0 years (range: 3-46 years). Almost all individuals were diagnosed with a PNET during routine TSC surveillance, 56.3% (n = 9) by MRI, 12.5% (n = 2) by CT, 25% (n = 4) by ultrasound, and 6.2% (n = 1) through a surgical procedure. Follow up after diagnosis involved 68.8% (n = 11) having serial imaging and nine of the sixteen individuals proceeding with surgical removal of the PNET. Eight individuals had a history of using systemic mTOR inhibitors. Tumor growth rate was slightly less in individuals taking an mTOR inhibitor (-0.8 mm/yr, IQR: -2.3 to 2.2) than those without (1.6 mm/yr; IQR: -0.99 to 5.01, p > 0.05). Conclusions: Nonfunctional PNETs occurred at younger ages in our TSC cohort and more commonly compared to ages and prevalence reported for the general population. PNETs in patients on systemic mTOR inhibitors had lower rates of growth. The outcome of this study provides preliminary evidence supporting the use of mTOR inhibitor therapy in conjunction with serial imaging as medical management for nonfunctional PNETs as an alternative option to invasive surgical removal.

Lymphangioleiomyomatosis Association with Underlying Genotype in Patients with Tuberous Sclerosis Complex.

Rationale: Lymphangioleiomyomatosis (LAM) is a female-predominant lung disease caused by mutations in the tuberous sclerosis complex (TSC) genes TSC1 and TSC2.Objectives: To examine the association between TSC mutation subtypes and the prevalence of LAM in women with TSC.Methods: Adult women seen at the Cincinnati Children's Hospital Medical Center's TSC clinic were stratified into the following three groups: those with TSC1 mutation, those with TSC2 mutation, and those with no mutation identified (NMI). Individual TSC manifestations were ascertained by blinded review of chest computed tomographic scans (LAM, multifocal micronodular pneumocyte hyperplasia, and sclerotic bone lesions) and chart review (all other manifestations). The association between mutation status and TSC manifestations was assessed by the Wilcoxon rank-sum test.Results: Our cohort consisted of 55 TSC women, including 30/55 (55%) with TSC2, 12/55 (22%) with TSC1, and 13/55 (23%) with NMI. Twenty-three women (42%) had characteristic cysts consistent with LAM, of whom 16 had TSC2 mutations and seven had NMI. The prevalence of LAM was higher in women with TSC2 mutations compared with women with TSC1 mutations (16/29 [55%] vs. 0/12; P = 0.003). Similarly, renal angiomyolipomas were more common in women with TSC2 mutations compared with women with TSC1 mutations (29/30 [97%] vs. 6/12 [50%]; P = 0.01). There was no association between TSC mutation subtype and the presence of multifocal micronodular pneumocyte hyperplasia, sclerotic bone lesions, and skin or brain involvement. Serum VEGF-D (vascular endothelial growth factor-D) concentrations (median [95% confidence interval]) tended to be higher in patients harboring TSC2 mutations compared with patients with TSC1 mutations (725 pg/ml [612-1,317] vs. 331 pg/ml [284-406]; P = 0.03) and in patients with LAM compared with patients without LAM (725 pg/ml [563-1,609] vs. 429 pg/ml [357-773]; P = 0.02).Conclusions: LAM and angiomyolipomas are more common in women with TSC harboring TSC2 mutations compared with women with TSC1 mutations. Serum VEGF-D is a useful biomarker to suggest the presence of LAM in women with TSC.

Pharmacological treatment strategies for subependymal giant cell astrocytoma (SEGA).

INTRODUCTION: Subependymal ependymal giant cell astrocytomas (SEGAs) occur almost exclusively in the setting of tuberous sclerosis (TSC). They are low-grade gliomas which typically produce clinical symptoms through either mass effect or hydrocephalus. As do other manifestations of tuberous sclerosis, these lesions result from mutations in either the TSC1 or the TSC2 gene. These mutations cause hyperactivation of the mechanistic target of rapamycin (mTOR). In view of their tendency to grow slowly, clinical symptoms usually only occur when the tumors reach a considerable size. Therapy can involve surgical resection, cerebrospinal fluid diversion, or medical therapy with an mTOR inhibitor. AREAS COVERED: Herein, the authors discuss the diagnosis, symptoms, and practical management of SEGAs as well as providing their expert opinion. EXPERT OPINION: mTOR inhibitors have largely replaced surgery as the primary modality for the management of SEGAs. Surgical treatment is largely limited to tumors that present with acute hydrocephalus and increased intracranial pressure. Patients with TSC should undergo periodic screening with CT or preferably MRI scans of the brain from childhood to approximately age 25 to identify SEGAs which require treatment. In addition to avoiding potential morbidity associated with surgical resection, mTOR inhibitors have the potential to improve the clinical status of tuberous sclerosis patients generally.

A systematic review on the burden of illness in individuals with tuberous sclerosis complex (TSC).

OBJECTIVE: This review will summarize current knowledge on the burden of illness (BOI) in tuberous sclerosis complex (TSC), a multisystem genetic disorder manifesting with hamartomas throughout the body, including mainly the kidneys, brain, skin, eyes, heart, and lungs. METHODS: We performed a systematic analysis of the available literature on BOI in TSC according to the PRISMA guidelines. All studies irrespective of participant age that reported on individual and societal measures of disease burden (e.g. health care resource use, costs, quality of life) were included. RESULTS: We identified 33 studies reporting BOI in TSC patients. Most studies (21) reported health care resource use, while 14 studies reported quality of life and 10 studies mentioned costs associated with TSC. Only eight research papers reported caregiver BOI. Substantial BOI occurs from most manifestations of the disorder, particularly from pharmacoresistant epilepsy, neuropsychiatric, renal and skin manifestations. While less frequent, pulmonary complications also lead to a high individual BOI. The range for the mean annual direct costs varied widely between 424 and 98,008 International Dollar purchasing power parities (PPP-$). Brain surgery, end-stage renal disease with dialysis, and pulmonary complications all incur particularly high costs. There is a dearth of information regarding indirect costs in TSC. Mortality overall is increased compared to general population; and most TSC related deaths occur as a result of complications from seizures as well as renal complications. Long term studies report mortality between 4.8 and 8.3% for a follow-up of 8 to 17.4 years. CONCLUSIONS: TSC patients and their caregivers have a high burden of illness, and TSC patients incur high costs in health care systems. At the same time, the provision of inadequate treatment that does not adhere to published guidelines is common and centralized TSC care is received by no more than half of individuals who need it, especially adults. Further studies focusing on the cost effectiveness and BOI outcomes of coordinated TSC care as well as of new treatment options such as mTOR inhibitors are necessary.

Cannabidiol Elevates Mechanistic Target of Rapamycin Inhibitor Levels in Patients With Tuberous Sclerosis Complex.

BACKGROUND: The mechanistic target of rapamycin inhibitors everolimus and sirolimus have activity against multiple manifestations of tuberous sclerosis complex and are approved to treat astrocytomas, angiomyolipomas, lymphangioleiomyomatosis, and epilepsy. Cannabidiol is a novel antiepileptic medication. There is lack of information regarding drug-drug interactions between mechanistic target of rapamycin inhibitors and cannabidiol in clinical practice. METHODS: We reviewed patients with tuberous sclerosis complex who were treated with a mechanistic target of rapamycin inhibitor (everolimus, sirolimus) and cannabidiol. Clinical information, mechanistic target of rapamycin inhibitor and cannabidiol dosing, concomitant antiepileptic drugs, as well as laboratory and adverse events were reviewed before and after initiation of cannabidiol. RESULTS: A total of 25 patients were treated with cannabidiol and a mechanistic target of rapamycin inhibitor (18 everolimus, seven sirolimus). All mechanistic target of rapamycin inhibitor levels were drawn as troughs. Levels were significantly higher in 76% patients after cannabidiol treatment (P = 0.0003). Median change from baseline was +9.8 ng/mL for everolimus and +5.1 ng/mL for sirolimus. Adverse events occurred in 40%, with diarrhea being the most frequent adverse event occurring in three patients. No severe adverse events occurred during the treatment period. CONCLUSIONS: Cannabidiol resulted in increased serum levels of everolimus and/or sirolimus. Some patients experienced doubling or tripling of their mechanistic target of rapamycin inhibitor trough following the addition of cannabidiol. In some cases, this resulted in clinical toxicity, as well as laboratory abnormalities. Awareness of this interaction can lead clinicians to evaluate serum levels and other safety laboratory studies more closely, and thereby avoid potentially significant adverse effects. In patients known to be prone to mechanistic target of rapamycin inhibitor toxicity, preemptive reduction in dose may be warranted upon initiation of cannabidiol.

mTOR Inhibitor Therapy for Tuberous Sclerosis Complex: Longitudinal Study of Muscle Mass Determined by Abdominal Cross-sectional Imaging with CT and MRI.

Purpose: To determine the effect of chronic mammalian target of rapamycin (mTOR) inhibition on skeletal muscle mass in patients with tuberous sclerosis complex (TSC). Materials and Methods: In this retrospective study, patients with TSC who were taking mTOR inhibitors and who underwent at least two abdominal CT or MRI examinations between 2005 and 2017 were included (n = 24; 14 males; mean age, 14.5 years ± 7.8 [standard deviation] at first examination). One reviewer drew regions of interest around psoas muscles at L3 to measure cross-sectional area. Multiple linear mixed-effect modeling was performed to evaluate the association between muscle mass and the covariates over time. Results: The 24 patients underwent a total of 129 abdominal CT or MRI examinations. Median duration of mTOR inhibition at last examination was 106 months (range, 1310-3717 days). There was no significant association between the duration of mTOR inhibitor therapy and psoas muscle area on multiple linear mixed-effect modeling (P = .055); however, patient height and height squared were significant predictors of psoas area (P = .014 and P < .0001, respectively). Conclusion: Duration of mTOR inhibition in TSC was not significantly associated with a decrease in psoas muscle area, suggesting that chronic mTOR inhibition is not associated with sarcopenia.Keywords: CT, MR-Imaging, Pediatrics© RSNA, 2020.

Congenital Lymphatic Malformation and Aortic Aneurysm in a Patient with TSC2 Mutation.

We present a 7-year-old boy with tuberous sclerosis and congenital segmental lymphedema (CSL) of the left leg, as well as two aortic aneurysms. He was treated with everolimus (EVE) since the age of 14 months. His CSL regressed under treatment with EVE. His first aneurysms required operative intervention at age of 17 months. Four months afterward a new aortic aneurysm had been detected above the Dracon graft, but this one remained stable since that time. The patient didn't experience severe side effects. EVE has been well tolerated without disturbance of somatic growth or serious adverse effect.

Everolimus as adjunctive therapy for tuberous sclerosis complex-associated partial-onset seizures.

Introduction: Tuberous sclerosis complex (TSC) is a rare genetic disorder resulting in benign tumors in various organs. It is caused by mutations in TSC1 or TSC2 genes causing hyperactivation of the mammalian target of rapamycin (mTOR) pathway. The majority of patients with TSC develop epilepsy, and approximately two-thirds become refractory to antiepileptic drugs (AEDs). Recently, the mTOR inhibitor everolimus was approved as adjunctive therapy for TSC-associated partial seizures. Areas covered: This article covers different characteristics of everolimus, including major clinical trials leading to its approval in TSC-associated partial seizures, safety concerns, drug pharmacokinetics/pharmacodynamics, and an overview of potential competitors and other agents used to treat TSC-associated seizures. Expert opinion: Unlike many other therapies for treating TSC-associated seizures, everolimus addresses the underlying pathophysiology of TSC, and since it has also been shown to improve other TSC manifestations such as subependymal giant cell astrocytomas and renal angiomyolipomas, everolimus provides a potential multisystemic therapy for TSC. An important avenue for future research is exploring the possible use of everolimus as a preventative treatment for seizures as there is the potential to prevent negative developmental outcomes associated with TSC.