Early epileptiform EEG activity in infants with tuberous sclerosis complex predicts epilepsy and neurodevelopmental outcomes.

OBJECTIVE: To study the association between timing and characteristics of the first electroencephalography (EEG) with epileptiform discharges (ED-EEG) and epilepsy and neurodevelopment at 24 months in infants with tuberous sclerosis complex (TSC). METHODS: Patients enrolled in the prospective Epileptogenesis in a genetic model of epilepsy - Tuberous sclerosis complex (EPISTOP) trial, had serial EEG monitoring until the age of 24 months. The timing and characteristics of the first ED-EEG were studied in relation to clinical outcome. Epilepsy-related outcomes were analyzed separately in a conventionally followed group (initiation of vigabatrin after seizure onset) and a preventive group (initiation of vigabatrin before seizures, but after appearance of interictal epileptiform discharges [IEDs]). RESULTS: Eighty-three infants with TSC were enrolled at a median age of 28 days (interquartile range [IQR] 14-54). Seventy-nine of 83 patients (95%) developed epileptiform discharges at a median age of 77 days (IQR 23-111). Patients with a pathogenic TSC2 variant were significantly younger (P-value .009) at first ED-EEG and more frequently had multifocal IED (P-value .042) than patients with a pathogenic TSC1 variant. A younger age at first ED-EEG was significantly associated with lower cognitive (P-value .010), language (P-value .001), and motor (P-value .013) developmental quotients at 24 months. In the conventional group, 48 of 60 developed seizures. In this group, the presence of focal slowing on the first ED-EEG was predictive of earlier seizure onset (P-value .030). Earlier recording of epileptiform discharges (P-value .019), especially when multifocal (P-value .026) was associated with higher risk of drug-resistant epilepsy. In the preventive group, timing, distribution of IED, or focal slowing, was not associated with the epilepsy outcomes. However, when multifocal IEDs were present on the first ED-EEG, preventive treatment delayed the onset of seizures significantly (P-value <.001). SIGNIFICANCE: Early EEG findings help to identify TSC infants at risk of severe epilepsy and neurodevelopmental delay and those who may benefit from preventive treatment with vigabatrin.

Fetal Brain Magnetic Resonance Imaging Findings Predict Neurodevelopment in Children with Tuberous Sclerosis Complex.

OBJECTIVE: To correlate fetal brain magnetic resonance imaging (MRI) findings with epilepsy characteristics and neurodevelopment at 2 years of age in children with tuberous sclerosis complex (TSC) to improve prenatal counseling. STUDY DESIGN: This retrospective cohort study was performed in a collaboration between centers of the EPISTOP consortium. We included children with definite TSC, fetal MRIs, and available follow-up data at 2 years of age. A pediatric neuroradiologist masked to the patient's clinical characteristics evaluated all fetal MRIs. MRIs were categorized for each of the 10 brain lobes as score 0: no (sub)cortical lesions or doubt; score 1: a single small lesion; score 2: more than one small lesion or at least one large lesion (>5 mm). Neurologic manifestations were correlated to lesion sum scores. RESULTS: Forty-one children were included. Median gestational age at MRI was 33.3 weeks; (sub)cortical lesions were detected in 97.6%. Mean lesion sum score was 4.5. At 2 years, 58.5% of patients had epilepsy and 22% had drug-resistant epilepsy. Cognitive, language, and motor development were delayed in 38%, 81%, and 50% of patients, respectively. Autism spectrum disorder (ASD) was diagnosed in 20.5%. Fetal MRI lesion sum scores were significantly associated with cognitive and motor development, and with ASD diagnosis, but not with epilepsy characteristics. CONCLUSIONS: Fetal cerebral lesion scores correlate with neurodevelopment and ASD at 2 years in children with TSC.

Neurite Outgrowth Inhibitor (NogoA) Is Upregulated in White Matter Lesions of Complex Cortical Malformations.

Complex cortical malformations (CCMs), such as hemimegalencephaly and polymicrogyria, are associated with drug-resistant epilepsy and developmental impairment. They share certain neuropathological characteristics including mammalian target of rapamycin (mTOR) activation and an atypical number of white matter neurons. To get a better understanding of the pathobiology of the lesion architecture, we investigated the role of neurite outgrowth inhibitor A (NogoA), a known regulator of neuronal migration. Epilepsy surgery specimens from 16 CCM patients were analyzed and compared with sections of focal cortical dysplasia IIB (FCD IIB, n = 22), tuberous sclerosis complex (TSC, n = 8) as well as healthy controls (n = 15). Immunohistochemistry was used to characterize NogoA, myelination, and mTOR signaling. Digital slides were evaluated automatically with ImageJ. NogoA staining showed a significantly higher expression within the white matter of CCM and FCD IIB, whereas cortical tubers presented levels similar to controls. Further analysis of possible associations of NogoA with other factors revealed a positive correlation with mTOR and seizure frequency. To identify the main expressing NogoA cell type, double staining revealed dysmorphic neuronal white matter cells. Increased NogoA expression is associated with profound inhibition of neuritic sprouting and therefore contributes to a decrease in neuronal network complexity in CCM patients.

Prediction of Neurodevelopment in Infants With Tuberous Sclerosis Complex Using Early EEG Characteristics.

Tuberous Sclerosis Complex (TSC) is a multisystem genetic disorder with a high risk of early-onset epilepsy and a high prevalence of neurodevelopmental comorbidities, including intellectual disability and autism spectrum disorder (ASD). Therefore, TSC is an interesting disease model to investigate early biomarkers of neurodevelopmental comorbidities when interventions are favourable. We investigated whether early EEG characteristics can be used to predict neurodevelopment in infants with TSC. The first recorded EEG of 64 infants with TSC, enrolled in the international prospective EPISTOP trial (recorded at a median gestational age 42 4/7 weeks) was first visually assessed. EEG characteristics were correlated with ASD risk based on the ADOS-2 score, and cognitive, language, and motor developmental quotients (Bayley Scales of Infant and Toddler Development III) at the age of 24 months. Quantitative EEG analysis was used to validate the relationship between EEG background abnormalities and ASD risk. An abnormal first EEG (OR = 4.1, p-value = 0.027) and more specifically a dysmature EEG background (OR = 4.6, p-value = 0.017) was associated with a higher probability of ASD traits at the age of 24 months. This association between an early abnormal EEG and ASD risk remained significant in a multivariable model, adjusting for mutation and treatment (adjusted OR = 4.2, p-value = 0.029). A dysmature EEG background was also associated with lower cognitive (p-value = 0.029), language (p-value = 0.001), and motor (p-value = 0.017) developmental quotients at the age of 24 months. Our findings suggest that early EEG characteristics in newborns and infants with TSC can be used to predict neurodevelopmental comorbidities.

Is autism driven by epilepsy in infants with Tuberous Sclerosis Complex?

OBJECTIVE: To evaluate the relationship between age at seizure onset and neurodevelopmental outcome at age 24 months in infants with TSC, as well as the effect on neurodevelopmental outcome of early versus conventional treatment of epileptic seizures with vigabatrin (80-150 mg/kg/day). METHODS: Infants with TSC, aged ≤4 months and without previous seizures were enrolled in a prospective study and closely followed with monthly video EEG and serial standardized neurodevelopmental testing (Bayley Scales of Infant Development and Autism Diagnostic Observation Schedule). RESULTS: Eighty infants were enrolled. At the age of 24 months testing identified risk of Autism Spectrum Disorder (ASD) in 24/80 children (30.0%), and developmental delay (DD) in 26/80 (32.5%). Children with epilepsy (51/80; 63.8%) had a higher risk of ASD (P = 0.02) and DD (P = 0.001). Overall, no child presented with moderate or severe DD at 24 months (developmental quotient < 55). In 20% of children abnormal developmental trajectories were detected before the onset of seizures. Furthermore, 21% of all children with risk of ASD at 24 months had not developed seizures at that timepoint. There was no significant difference between early and conventional treatment with respect to rate of risk of ASD (P = 0.8) or DD (P = 0.9) at 24 months. INTERPRETATION: This study confirms a relationship between epilepsy and risk of ASD/DD. However, in this combined randomized/open label study, early treatment with vigabatrin did not alter the risk of ASD or DD at age 2 years.

Effects of the ketogenic diet on platelet counts and global coagulation tests in childhood epilepsy.

PURPOSE: Several antiseizure drugs (ASD), especially Valproic acid (VPA), influence platelet counts and coagulation parameters. The ketogenic diet (KD), established in drug-resistant epilepsy, is combined with ASDs. Bruising and prolonged bleeding times during KD have been described, but whether hemostatic changes result from the KD or from concomitant ASDs, remains unclear. Aim of the present study was to evaluate bleeding, platelet counts and global coagulation tests prior to and during KD in childhood epilepsy. METHOD: Consecutive children treated with KD were systematically observed for bleeding. Serial measurements of platelet counts and global coagulation tests (APTT, PT and fibrinogen) were obtained at baseline and during KD (at 1, 3, 6 and 12 months). Children with KD monotherapy, concomitant VPA, or other ASDs were compared. RESULTS: Among 162 children receiving KD, we observed neither bleeding in daily life nor perioperative bleeding in those undergoing surgery (n = 25). Most children had normal platelet counts and coagulation parameters. Only a few had transient mild thrombocytopenia and mildly prolonged APTT values, not indicative of a bleeding risk. Even KD combined with VPA did not cause relevant coagulopathy. Unexpectedly, we found mild thrombocytosis in 24 % of patients prior to KD, which was most pronounced in yet untreated epilepsy. Thrombocytosis steadily resolved during KD. CONCLUSIONS: During KD treatment of childhood epilepsy, we observed neither bleeding symptoms nor laboratory results indicating a bleeding risk. Unexpectedly, mild thrombocytosis was present in 24 % at baseline, normalising during KD. Thrombocytosis may reflect the underlying inflammatory process of untreated epilepsy and requires further study.

The coding and non-coding transcriptional landscape of subependymal giant cell astrocytomas.

Tuberous sclerosis complex (TSC) is an autosomal dominantly inherited neurocutaneous disorder caused by inactivating mutations in TSC1 or TSC2, key regulators of the mechanistic target of rapamycin complex 1 (mTORC1) pathway. In the CNS, TSC is characterized by cortical tubers, subependymal nodules and subependymal giant cell astrocytomas (SEGAs). SEGAs may lead to impaired circulation of CSF resulting in hydrocephalus and raised intracranial pressure in patients with TSC. Currently, surgical resection and mTORC1 inhibitors are the recommended treatment options for patients with SEGA. In the present study, high-throughput RNA-sequencing (SEGAs n = 19, periventricular control n = 8) was used in combination with computational approaches to unravel the complexity of SEGA development. We identified 9400 mRNAs and 94 microRNAs differentially expressed in SEGAs compared to control tissue. The SEGA transcriptome profile was enriched for the mitogen-activated protein kinase (MAPK) pathway, a major regulator of cell proliferation and survival. Analysis at the protein level confirmed that extracellular signal-regulated kinase (ERK) is activated in SEGAs. Subsequently, the inhibition of ERK independently of mTORC1 blockade decreased efficiently the proliferation of primary patient-derived SEGA cultures. Furthermore, we found that LAMTOR1, LAMTOR2, LAMTOR3, LAMTOR4 and LAMTOR5 were overexpressed at both gene and protein levels in SEGA compared to control tissue. Taken together LAMTOR1-5 can form a complex, known as the 'Ragulator' complex, which is known to activate both mTORC1 and MAPK/ERK pathways. Overall, this study shows that the MAPK/ERK pathway could be used as a target for treatment independent of, or in combination with mTORC1 inhibitors for TSC patients. Moreover, our study provides initial evidence of a possible link between the constitutive activated mTORC1 pathway and a secondary driver pathway of tumour growth.

The Ketogenic Diet Including Breast Milk for Treatment of Infants with Severe Childhood Epilepsy: Feasibility, Safety, and Effectiveness.

Objective: The ketogenic diet (KD) is a high-fat and restricted carbohydrate diet for treating severe childhood epilepsy. In infants, breast milk is usually fully replaced by a ketogenic formula. At our center, mothers are encouraged to include breastfeeding into the KD if still breastfeeding. This retrospective study describes achievement and maintenance of ketosis with or without inclusion of breast milk. Methods: Data were retrieved from a prospective longitudinal database of children treated with KD for epilepsy analyzing infants <1 year of age. The time to achieve clinically relevant ketosis (≥2 mmol/L beta-hydroxybutyrate) was compared with and without inclusion of breast milk into standard KD. Ketosis, nutritional intakes, effectiveness, adverse effects, and successful continuation of breastfeeding were evaluated. Results: A total of 79 infants were eligible for analysis. In 20% (16), breast milk was included. Infants with breast milk included into the KD achieved relevant ketosis in 47 hours (interquartile range [IQR] 24-95) compared with 41 hours (IQR 22-70; p = 0.779) in infants with standard KD. Beta-hydroxybutyrate at day 2 was 3.1 mmol/L (IQR 0.5-4.9) and 3.8 mmol/L (IQR 2.2-4.9). Infants with breast milk included received higher amounts of carbohydrates at baseline and calories at 3 months. Seizure freedom and adverse effects showed no relevant differences. No infections occurred in infants receiving breast milk. In two infants, KD was initiated with breast-feds after bottle-feeding KD formula. In 31%, breastfeeding was continued after the KD, and in 25%, inclusion of breast milk and breastfeeding was maintained until complete weaning. Before discharge from hospital, the amount of breast milk included was median 90 mL/day (IQR 53-203) equivalent to median 9% (IQR 6-15). Conclusions: Appropriate ketosis was achieved in most infants and maintained within 48 hours. Incorporation of breast milk into KD is feasible, safe, and effective.

Pathophysiology of neurodevelopmental mTOR pathway-associated epileptic conditions: Current status of biomedical research.

Epilepsy is one of the most common and serious neurological disorders worldwide. It has no identifiable cause in approximately 50% of patients; in the other 50%, the condition may be due to a variety of etiologies and pathomechanisms. In this review, special focus is put on the prototypes of "mTORpathies": tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD) type IIb. We review recent research data on mTORpathies, with emphasis on cortical tubers and FCD-like lesions (neuronal migration lines (NML)). A major pathologic aspect in the network of drug-resistant epilepsy progression is the limited myelination of the white matter observed in these lesions. Recently, an association between the myelin pathology and dysregulation of the mTOR signaling pathway was observed by several studies. The lowered myelin content was shown to correlate not only with an increased mTOR expression but also with the relative duration of epilepsy. Another recently published finding in surgical tissue from patients with drug-resistant epilepsy and malformations of cortical development is inflammation. Accumulating evidence reports persistent and complex activation of inflammatory pathways in both cortical tubers and FCD lesions. Due to the fact that cortical tubers, as well as FCD lesions, are highly epileptogenic, a possible link between chronic seizure activity and the occurrence of an inflammatory response observed within the dysplastic cortex was postulated. Previously, alterations in the levels of classical complement C1q-C3 molecules in experimental and human epilepsy have been reported, suggesting that the classical complement pathway may be a novel candidate mechanism for the underlying epileptogenic circuit mechanism.
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Early Clinical Predictors of Autism Spectrum Disorder in Infants with Tuberous Sclerosis Complex: Results from the EPISTOP Study.

Autism spectrum disorder (ASD) is highly prevalent in subjects with Tuberous Sclerosis Complex (TSC), but we are not still able to reliably predict which infants will develop ASD. This study aimed to identify the early clinical markers of ASD and/or developmental delay (DD) in infants with an early diagnosis of TSC. We prospectively evaluated 82 infants with TSC (6-24 months of age), using a detailed neuropsychological assessment (Bayley Scales of Infant Development-BSID, and Autism Diagnostic Observation Schedule-ADOS), in the context of the EPISTOP (Long-term, prospective study evaluating clinical and molecular biomarkers of EPIleptogenesiS in a genetic model of epilepsy-Tuberous SclerOsis ComPlex) project (NCT02098759). Normal cognitive developmental quotient at 12 months excluded subsequent ASD (negative predictive value 100%). The total score of ADOS at 12 months clearly differentiated children with a future diagnosis of ASD from children without (p = 0.012). Atypical socio-communication behaviors (p < 0.001) were more frequently observed than stereotyped/repetitive behaviors in children with ASD at 24 months. The combined use of BSID and ADOS can reliably identify infants with TSC with a higher risk for ASD at age 6-12 months, allowing for clinicians to target the earliest symptoms of abnormal neurodevelopment with tailored intervention strategies.

Efficacy and tolerability of the ketogenic diet versus high-dose adrenocorticotropic hormone for infantile spasms: A single-center parallel-cohort randomized controlled trial.

OBJECTIVE: To compare the efficacy and safety of the ketogenic diet (KD) with standard adrenocorticotropic hormone (ACTH) treatment in infants with West syndrome. METHODS: In this parallel-cohort (PC) randomized controlled trial (RCT), infants were randomly allocated to KD or high-dose ACTH. Those who could not be randomized were followed in a PC. Primary end point was electroclinical remission at day 28. Secondary end points were time to electroclinical remission, relapse after initial response, seizure freedom at last follow-up, adverse effects, and developmental progress. RESULTS: One hundred one infants were included: 32 in the RCT (16 KD; 16 ACTH) and 69 in the PC (37 KD; 32 ACTH). Electroclinical remission at day 28 was similar between KD and ACTH (RCT: 62% vs 69%; PC: 41% vs 38%; combined cohort: 47% vs 48%; KD vs ACTH, respectively). In the combined cohort, time to electroclinical remission was similar between both treatments (14 days for KD, 16 days for ACTH). However, relapse rates were 16% (KD) and 43% (ACTH, P = 0.09), and seizure freedom at last follow-up was 40% (KD) and 27% (ACTH, P = 0.18). Adverse effects needing acute medical intervention occurred more often with ACTH (30% with KD, 94% with ACTH, P < 0.001). Age-appropriate psychomotor development and adaptive behavior were similar. Without prior vigabatrin (VGB) treatment, remission at day 28 was 47% (KD) and 80% (ACTH, P = 0.02); relapse rates were 29% (KD) and 56% (ACTH, P = 0.13). Consequently, seizure freedom at last follow-up was similar. In infants with prior VGB, seizure freedom at last follow-up was 48% (KD) and 21% (ACTH, P = 0.05). SIGNIFICANCE: The study is underpowered; therefore, its results should be interpreted with caution. KD is as effective as ACTH in the long term but is better tolerated. Without prior VGB treatment, ACTH remains the first choice to achieve short-term remission. However, with prior VGB, KD was at least as effective as ACTH in the short term and was associated with lower relapse rates in the long term; therefore, it represents an appropriate second-line treatment after VGB.

Single stage epilepsy surgery in children and adolescents with focal cortical dysplasia type II - Prognostic value of the intraoperative electrocorticogram.

OBJECTIVE: To evaluate prospectively the informative/prognostic value of epileptic discharges in the post-resection ECoGs of children with drug-resistant epilepsies and Focal Cortical Dysplasia type II (FCD-II). METHODS: Included were consecutive patients with focal epilepsies and suspected FCD-II who were planned for single-stage epilepsy surgery based on non-invasive presurgical evaluation results. Intraoperative ECoGs were recorded using a 32-channel system with strip- and/or grid-electrodes. Spikes were defined as transients with a mainly negative component and duration of 20-70 ms. Fast activity was defined as rhythmic bursts of polyspikes >13 Hz. All ECoGs were analysed visually. The significance of both spikes and fast activity in the post-resection ECoG for seizure outcomes 24 months after surgery was evaluated. RESULTS: Data from 18 patients (five girls) were analysed. 10/18 patients (55.6%) showed spikes in their post-resection ECoGs, five of them showed additional fast activity. 24 months after surgery, 12/18 patients (66.7%) were seizure-free. There was a significant correlation between unfavorable seizure outcomes and fast activity in the post-resection ECoGs (p = 0.009), whereas spikes alone were not predictive (p = 0.502). CONCLUSION: Even when recorded with non-sophisticated techniques, presence of fast activity in post-resection ECoGs might be a valid negative outcome-predictor after surgery in paediatric patients with FCD-II associated drug-resistant epilepsies. SIGNIFICANCE: Fast activity recorded with a relatively simple ECoG equipment seems also to have prognostic significance and by this might be an alternative to HFOs recorded with highly sophisticated and expensive technologies.

Everolimus in infants with tuberous sclerosis complex-related West syndrome: First results from a single-center prospective observational study.

Tuberous sclerosis complex (TSC) is the most common cause of West syndrome (WS). Currently available treatment options are ineffective in the majority of affected infants and/or associated with potential serious side effects. Based on the assumption that mTOR overactivation results in increased neuroexcitability in TSC, mTOR inhibitors have been studied as antiseizure therapy. As a result, everolimus recently received approval for the adjunctive treatment of patients aged ≥2 years with refractory TSC-associated focal and secondary generalized seizures. However, efficacy and safety data for infants with TSC-associated WS are still lacking. Therefore, a prospective open-label observational study was initiated at our center, to evaluate everolimus add-on treatment in infants with TSC-associated WS, previously refractory to standard treatment. For this preliminary report, data from four male infants with TSC2 and a median observation period of 13 (range = 8-42) months after treatment initiation were analyzed. Two infants showed electroclinical remission until day 14 after everolimus treatment initiation. In one additional infant, hypsarrhythmia resolved. No relapse after initial response was documented. Developmental progress improved in three infants. Tolerability was similar to that described in older children. According to our preliminary results, everolimus appears to have the potential to treat successfully both spasms and hypsarrhythmia in infants with TSC-associated WS, contributing to better developmental progress.

Ketogenic parenteral nutrition in 17 pediatric patients with epilepsy.

Objective: Ketogenic parenteral nutrition (kPN) is indicated when enteral intake is temporarily limited or impossible, but evidence-based prescriptions are lacking. Objective was to evaluate the efficacy and safety of kPN in children with epileptic encephalopathies using a new computer-based algorithm for accurate component calculating. Methods: Children with epilepsy receiving kPN were included. A computer-based algorithm was established on the basis of guidelines of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN): fat intake not exceeding 4 g/kg/day, age-adequate supply of protein, electrolytes, vitamins, and trace elements, but reduced carbohydrates. Primary outcome was successfully reaching relevant ketosis, defined as beta-hydroxybutyrate plasma level of ≥ 2 mmol/L. Efficacy was defined as seizure reduction ≥50% in de novo kPN and maintenance of response in children already on a ketogenic diet (KD). Safety was assessed by adverse effects, laboratory findings, and the appropriateness of nutritional intake. Results: Seventeen children (median 1.84 years) were studied, of which 76% (13/17) were already on an oral ketogenic diet. Indications for kPN were surgery, status epilepticus, vomiting, food refusal, and introduction of enteral feeding in neonates. The parenteral fat/nonfat ratio was mean 0.9 (±0.3; range 0.6-1.5). Relevant ketosis was reached in 10 children (median 2.9 mmol/L), but not in 7 (median = 1.4 mmol/L). In de novo kPN, significant response was observed in 50% (2/4); in patients previously responding to the KD (77%, 10/13), response was maintained. A significant correlation between the degree of ketosis and seizure reduction (correlation coefficient = 0.691; p = .002) was observed. Only mild and transient adverse events occurred during kPN. Significance: KPN with fat intake of 3.5-4.0 g/kg/day was safe and effective. KPN was tailored according to guidelines and individual nutritional needs. In nearly half of the patients, ketosis was lower than during oral KD. Despite this, seizures remained controlled.

Impaired oligodendroglial turnover is associated with myelin pathology in focal cortical dysplasia and tuberous sclerosis complex.

Conventional antiepileptic drugs suppress the excessive firing of neurons during seizures. In drug-resistant patients, treatment failure indicates an alternative important epileptogenic trigger. Two epilepsy-associated pathologies show myelin deficiencies in seizure-related brain regions: Focal Cortical Dysplasia IIB (FCD) and cortical tubers in Tuberous Sclerosis Complex (TSC). Studies uncovering white matter-pathology mechanisms are therefore urgently needed to gain more insight into epileptogenesis, the propensity to maintain seizures, and their associated comorbidities such as cognitive defects. We analyzed epilepsy surgery specimens of FCD IIB (n = 22), TSC (n = 8), and other malformations of cortical development MCD (n = 12), and compared them to autopsy and biopsy cases (n = 15). The entire lesional pathology was assessed using digital immunohistochemistry, immunofluorescence and western blotting for oligodendroglial lineage, myelin and mTOR markers, and findings were correlated to clinical parameters. White matter pathology with depleted myelin and oligodendroglia were found in 50% of FCD IIB and 62% of TSC cases. Other MCDs had either a normal content or even showed reactive oligodendrolial hyperplasia. Furthermore, myelin deficiency was associated with increased mTOR expression and the lower amount of oligodendroglia was linked with their precursor cells (PDGFRa). The relative duration of epilepsy (normalized to age) also correlated positively to mTOR activation and negatively to myelination. Decreased content of oligodendroglia and missing precursor cells indicated insufficient oligodendroglial development, probably mediated by mTOR, which may ultimately lead to severe myelin loss. In terms of disease management, an early and targeted treatment could restore normal myelin development and, therefore, alter seizure threshold and improve cognitive outcome.

Efficacy and safety of Everolimus in children with TSC - associated epilepsy - Pilot data from an open single-center prospective study.

BACKGROUND: Epilepsy occurs in up to 90 % of all individuals with tuberous sclerosis complex (TSC). In 67 % disease onset is during childhood. In ≥ 50 % seizures are refractory to currently available treatment options. The mTOR-Inhibitor Everolimus (Votubia®) was approved for the treatment of subependymal giant cell astrocytoma (SEGA) and renal angiomyolipoma (AML) in Europe in 2011. It's anticonvulsive/antiepileptic properties are promising, but evidence is still limited. Study aim was to evaluate the efficacy and safety of Everolimus in children and adolescents with TSC-associated epilepsies. METHODS: Inclusion-criteria of this investigator-initiated, single-center, open, prospective study were: 1) the ascertained diagnosis of TSC; 2) age ≤ 18 years; 3) treatment indication for Votubia® according to the European Commission guidelines; 4) drug-resistant TSC-associated epilepsy, 5) prospective continuous follow-up for at least 6 months after treatment initiation and 6) informed consent to participate. Votubia® was orally administered once/day, starting with 4.5 mg/m2 and titrated to achieve blood trough concentrations between 5 and 15 ng/ml. Primary endpoint was the reduction in seizure frequency of ≥ 50 % compared to baseline. RESULTS: Fifteen patients (nine male) with a median age of six (range; 1-18) years fulfilled the inclusion criteria. 26 % (4/15) had TSC1, 66 % (10/15) had TSC2 mutations. In one patient no mutation was found. Time of observation after treatment initiation was median 22 (range; 6-50) months. At last observation, 80 % (12/15) of the patients were responders, 58 % of them (7/12) were seizure free. The overall reduction in seizure frequency was 60 % in focal seizures, 80 % in generalized tonic clonic seizures and 87 % in drop attacks. The effect of Everolimus was seen already at low doses, early after treatment initiation. Loss of efficacy over time was not observed. Transient side effects were seen in 93 % (14/15) of the patients. In no case the drug had to be withdrawn. CONCLUSION: Everolimus seems to be an effective treatment option not only for SEGA and AML, but also for TSC-related epilepsies. Although there are potential serious side effects, treatment was tolerated well by the majority of patients, provided that patients are under close surveillance of epileptologists who are familiar with immunosuppressive agents.

Childhood onset temporal lobe epilepsy: Beyond hippocampal sclerosis.

OBJECTIVE: Hippocampal Sclerosis (HS) is widely recognized as a significant underlying cause of drug-resistant temporal lobe epilepsy (TLE) in adults. In contrast, HS is a rare finding in pediatric surgical series, and a higher incidence of HS associated with cortical dysplasia (i.e. FCD type IIIa according to the new ILAE classification) than in adult series has been reported. Data about the electro-clinical characteristics of this subgroup are scarce. METHODS: We studied 15 children and adolescents with drug-resistant TLE and HS who had anterior temporal lobe resection at our center with regard to electroclinical characteristics, MRI features and histopathology. Children in whom histopathology was consistent with Focal Cortical Dysplasia (FCD) type IIIa (n = 7) were compared with those who had HS only (n = 8). RESULTS: Clinical characteristics associated with this highly selective subset of patients with FCD type IIIa were: the presence of febrile seizures during infancy, a shorter duration of active epilepsy and a lower age at epilepsy surgery. In addition, there were non-significant trends towards more extended abnormalities on both EEG and neuroimaging. We were, however, not able to find group differences with respect to neuropathologic subtyping of the HS. CONCLUSION: We present the first detailed description and comprehensive data analysis of children with FCD type IIIa. According to our results, this patient group seems to show a distinct clinical phenotype.

The ketogenic diet in infants--Advantages of early use.

OBJECTIVE: To evaluate the efficacy and safety of the ketogenic diet (KD) in infants (< 1.5 years of age) compared with older children. METHODS: Patients with complete follow-up data of ≥ 3 months after initiation of the KD were analyzed retrospectively. Infants < 1.5 years at initiation of the KD (Group A) were compared with children > 1.5 years (Group B). RESULTS: 127 children were screened, 115 (Group A: 58/Group B: 57) were included. There were no significant differences between groups with respect to responder rates (63.8% vs. 57.9% at 3 months), but more infants became seizure free (34.5% vs. 19% at 3 months; 32.7% vs. 17.5% at 6 and 12 months). This result remained stable also after termination of the KD (30.6% vs. 3.9% at last follow-up) (p = 0.000). Looking at infants < 9 months of age separately (n = 42), this result was even stronger with significantly more infants being seizure free at 6 and at 12 months (p = 0.005, p = 0.014, respectively). In addition, a significantly higher number of infants remained seizure free in the long-term (p = 0.001). No group differences between infants and children with respect to safety were observed. Overall 52/115 patients (45.21%) reported side effects, but withdrawal of the KD was only necessary in one infant. Acceptance of the KD was better in infants compared with children at 3 months (0 vs. 14, p = 0.000), but became difficult when solid food was introduced (16 vs. 14; n.s.). SIGNIFICANCE: According to our results, the KD is highly effective and well tolerated in infants with epilepsy. Seizure freedom is more often achieved and maintained in infants. Acceptance of the diet is better before the introduction of solid food. Therefore, we recommend the early use of the KD during the course of epilepsy.