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PURPOSE: To perform comprehensive genotyping of TSC1 and TSC2 in a cohort of 94 infants with tuberous sclerosis complex (TSC) and correlate with clinical manifestations. METHODS: Infants were enrolled at age

Backgroud Drug-resistant epilepsy is the main risk factor for future intellectual disability in patients with tuberous sclerosis complex. Clinical epileptic seizures are often preceded by electroencephalographic changes, which provide an opportunity for preventive treatment. We evaluated the neuropsychologic and epilepsy outcomes at school age in children with tuberous sclerosis complex who received preventive antiepileptic treatment in infancy. Methods We performed a prospective, nonrandomized clinical trial with 14 infants diagnosed with tuberous sclerosis complex in whom serial electroencephalographic recordings were performed and preventive treatment with vigabatrin initiated when active epileptic discharges were detected. An age-matched control group consisted of 31 infants with tuberous sclerosis complex in whom treatment with vigabatrin was given only after onset of clinical seizures. Results of clinical assessment of epilepsy and cognitive outcomes were analyzed. Results All patients in the preventive group (n = 14) and 25 of 31 patients in the standard treatment group were followed through minimum age five years, median 8.8 and 8.0 years in the preventive and standard groups, respectively. The median intelligence quotient was 94 for the preventive group when compared with 46 for the standard group (P Conclusions This study provides evidence that preventive antiepileptic treatment in infants with tuberous sclerosis complex improves long-term epilepsy control and cognitive outcome at school age.

Objective The aim of this study is the investigation of early-life EEG background abnormalities or “dysmature” traits in infants with tuberous sclerosis complex (TSC) and their capacity to predict autism spectrum disorder or neurodevelopmental outcome. Methods EEG data were prospectively collected from TSC patients during the EPISTOP trial (NCT02098759). Subjects were younger than 4 months, and ASD risk and neurodevelopmental outcome were assessed at the age of 2 years. The EEG at the first visit was analyzed by means of Multiscale Entropy (MSE), multifractality (MFA), amplitude integrated EEG features and topological indices of the EEG network. These features were associated with both ASD and abnormal Bayley outcome of the infants using linear discriminant analysis. Results The classification of the ASD patients shows that MFA and MSE had the best discrimination performances, with an area under the ROC curve AUC (MFA) = 0.74 and AUC(MSE) = 0.79 respectively, and kappa scores of Kappa(MFA) = 0.48 and Kappa(MSE) = 0.26. Concerning both abnormal Bayley outcome and ASD, the developmental abnormalities detection shows that entropy and fractal features outperform the other subsets of attributes and the multiclass analysis shows that those features can also discriminate patients with ASD from patients with only developmental abnormalities (Kappa(MFA) = 0.41 and Kappa(MSE) = 0.36). Conclusion Quantitative EEG analysis shows that a dysmature EEG, i.e. a signal with higher fractal regularity and lower entropy, is associated with autism spectrum disorder or abnormal Bayley outcome at 2 years of age.

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.

BackgroundEpilepsy develops in 70–90% of children with Tuberous Sclerosis Complex (TSC) and is often resistant to medication. Treatment with mTOR pathway inhibitors is an important therapeutic option in drug-resistant epilepsy associated with TSC. Our study evaluated the antiepileptic effect of rapamycin in the pediatric population of patients diagnosed with TSC.MethodsThis single center, open-label study evaluated safety and anti-epileptic efficacy of 12 months of rapamycin treatment in 32 patients aged from 11 months to 14 years with drug-resistant TSC- associated epilepsy.ResultsAfter the first 6 months of treatment, the improvement in seizure frequency, defined as at least a 50% reduction in the number of seizures per week compared to baseline, was seen in 18 individuals (56.25%). We observed no change in 12 individuals (37.5%) and worsening, defined as increase in the number of seizures—in 2 patients (6.25%). The overall improvement defined as at least a 50% reduction in seizure frequency was found in 65.6% of all patients after 12 months with 28% of patients obtaining complete remission. Another five patients experienced at least an 80% reduction in the frequency of seizures. Concomitant treatment with vigabatrin, and to a much lesser extent topiramate and levetiracetam, was an additional favorable prognostic factor for the success of the therapy. A linear relationship between the cumulative dose of rapamycin and its therapeutic effect was observed. The safety profile of the drug was satisfactory. In none of the observed cases did the adverse events reach the level that required withdrawal of the rapamycin treatment. The reason for dropouts was insufficient drug efficacy in 3 cases.ConclusionsLong-term use of rapamycin, especially in combination with vigabatrin, might be a beneficial therapeutic option in the treatment of drug-resistant epilepsy in children with TSC.

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

PPP3CA encodes calmodulin-binding catalytic subunit of calcineurin, a ubiquitously expressed calcium/calmodulin-regulated protein phosphatase. Recently de novo PPP3CA variants were reported as a cause of disease in 12 subjects presenting with epileptic encephalopathy and dysmorphic features. We describe a boy with similar phenotype and severe early onset epileptic encephalopathy in whom a novel de novo c.1324C>T (p.(Gln442Ter)) PPP3CA variant was found by whole exome sequencing. Western blot experiments in patient's cells (EBV transformed lymphocytes and neuronal cells derived through reprogramming) indicate that despite normal mRNA abundance the protein expression level is strongly reduced both for the mutated and wild-type protein. By in vitro studies with recombinant protein expressed in E. coli we show that c.1324C>T (p.(Gln442Ter)) results in constitutive activation of the enzyme. Our results confirm the role of PPP3CA defects in pathogenesis of a distinct neurodevelopmental disorder including severe epilepsy and dysmorphism and provide further functional clues regarding the pathogenic mechanism.

The purpose of this study was to evaluate the epidemiology and clinical significance of hepatic angiomyolipomas in patients with tuberous sclerosis complex.We performed a retrospective analysis of clinical and imaging data from 187 patients with tuberous sclerosis complex. The prevalence, progression, and potential relationship between liver lesions and other clinical findings, including genetic associations, were assessed.Twenty-eight of 187 patients (14.9%) had hepatic lesions. There was a predominance of female over male patients in individuals with liver lesions (17 versus 11), with statistical significance in patients under five years of age (P 0.05). All individuals having hepatic lesions who also had available genetic testing data (n = 20) were diagnosed with a TSC2 gene mutation. All patients with liver lesions had coexisting renal angiomyolipomas (AMLs) (P 0.05). The age of onset of renal lesions was lower and their prevalence was significantly higher in patients with liver involvement (P 0.05). In most instances, hepatic lesions measured several millimeters in diameter and were clinically asymptomatic. Progressive lesion growth was documented in six individuals but with no clinical consequences to date.This study confirms the association of hepatic lesions with TSC2 mutations, a common origin of liver and renal AMLs, as well as the predominance of female patients in this group. Hepatic AMLs are relatively common but mostly benign lesions.

Background Epilepsy affects up to 90% of TSC patients and majority of them have seizure at the age of 3–5 months, after a period of latent epileptogenesis, but some develop epilepsy earlier. Aims The aim of this work was to identify incidence, clinical characteristics, and risk factors for neonatal onset of epilepsy in a large cohort of TSC patients. Methods A retrospective review of medical data of 421 TSC patients was performed. Patients who developed epilepsy within first 4 weeks of life were included in the study. Clinical and treatment data, EEG, MRI, and genetic analyses were assessed. Results Epilepsy was present in 366 (86.9%) patients. Twenty-one (5.7%) developed epilepsy as newborns. Mean follow-up was 44.86 (6–170) months. Six patients were seizure free and 15 had drug-resistant seizures at the end of follow-up. Mental retardation was found in 81% of patients. In 11 (52.4%) patients brain MRI revealed large malformations of cerebral cortex, meeting the criteria for focal cortical dysplasia (FCD). FCD was revealed in both TSC1 and TSC2 mutation cases. Other risk factors for neonatal epilepsy included: perinatal complications and congenital SEGAs. Presence of FCD was associated with more severe epilepsy and worse neuropsychological outcome. Epilepsy surgery resulted in improvement in seizure control. Conclusions Neonatal onset of epilepsy in TSC is frequently associated with large malformations of cerebral cortex. Patients with FCD are at high risk of severe drug-resistant epilepsy and poor neuropsychological outcome. Early epilepsy surgery may be beneficial and should be considered in such cases.

BACKGROUND: Subependymal giant cell astrocytoma is a brain tumor associated with tuberous sclerosis complex. There are two treatment options for subependymal giant cell astrocytomas: surgery or mammalian target of rapamycin inhibitor. The analysis of outcome of subependymal giant cell astrocytoma surgery may help characterize the patients who may benefit from pharmacotherapy. METHODS: Sixty-four subependymal giant cell astrocytoma surgeries in 57 tuberous sclerosis complex patients with at least a 12-month follow-up were included in the study. The tumor size, age of the patients, mutation in the TSC1 or TSC2 gene, indication for the surgery, and postsurgical complications were analyzed. RESULTS: The mean age of patients at surgery was 9.7 years. Mean follow-up after surgery was 63.7 months. Thirty-seven (57.8%) tumors were symptomatic and 27 (42.2%) were asymptomatic. Patients with TSC2 mutations developed subependymal giant cell astrocytoma at a significantly younger age than individuals with TSC1 mutations. Four patients (6.2% of all surgeries) died after surgery. Surgeryrelated complications were reported in 0%, 46%, 83%, 81%, and 67% of patients with tumors 4 cm, and bilateral subependymal giant cell astrocytomas, respectively, and were most common in children younger than 3 years of age. The most common complications included hemiparesis, hydrocephalus, hematoma, and cognitive decline. CONCLUSIONS: Our study indicates that subependymal giant cell astrocytoma surgery is associated with significant risk in individuals with bilateral subependymal giant cell astrocytomas, tumors bigger than 2 cm, and in children younger than 3 years of age. Therefore, tuberous sclerosis complex patients should be thoroughly screened for subependymal giant cell astrocytoma growth, and early treatment should be considered in selected patients.

BackgroundEpilepsy appears in 70–80% of patients with tuberous sclerosis complex, most commonly in the first year of age. Early manifestation of epilepsy is associated with drug-resistant epilepsy and mental retardation in more than 80% of patients. Clinical epileptic seizures are preceded by deterioration of EEG recording thus infants with high risk of epilepsy can be identified.AimsWe hypothesized that preventative antiepileptic treatment of infants with multifocal activity on EEG might lower the incidence of drug-resistant epilepsy and mental retardation.MethodsForty-five infants with early diagnosis of tuberous sclerosis complex were included in the open-label study. They were divided in two groups: standard (n=31) and preventative one (n=14). In standard group the antiepileptic treatment was launched early, but after the onset of seizures. In preventative group medication was commenced when active epileptic discharges were seen on EEG, but before the onset of clinical seizures. Children were followed till the end of 2 years of age.ResultsAt 24 months of age mental retardation was significantly more frequent and severe in “standard” vs “preventative” group (48% vs 14%; p=0.031; mean IQ score 68.7 vs 92.3; p

Summary Purpose: The aim of the study was to reveal the relationships between the tuber count of the brain found in patients with tuberous sclerosis complex (TSC) and their cognitive outcome. Methods: A single-center, retrospective analysis was performed of patients with documented TSC seen from 1988 to 2010 at the Children’s Memorial Health Institute, Warsaw, Poland. Key Findings: Sixty-two patients were analyzed, and there was a significant correlation between younger age at the first seizure and developmental delay. The patients who did not develop seizures had normal development, despite some presenting with higher tuber load than those with seizures. There was a statistically significant negative correlation between the number of tubers within the right temporal lobe and cognition. Significance: Our findings confirm our hypothesis that the cognitive outcome in TSC is more dependent on the age of the seizure onset rather than on the tuber count.

OBJECTIVE. Tuberous sclerosis complex is an autosomal dominant disorder in which hamartomas occur in several organs. Cardiac rhabdomyomas, the most common heart tumors of childhood, are well known to be associated with tuberous sclerosis complex. Our aim for this study was to characterize the incidence, progression, and clinical consequences of tuberous sclerosis complex–associated rhabdomyomas in a large cohort of patients with TSC1 and TSC2 genotypes. PATIENTS AND METHODS. Patients (154) with tuberous sclerosis complex were evaluated, including clinical assessment, electrocardiography, and echocardiography. Mutations in TSC1 or TSC2 genes were identified in 127 patients. RESULTS. Cardiac rhabdomyomas were found in 74 (48%) patients. Tumors were most frequent in children younger than 2 years (65%). Tumor regression or disappearance was observed in 37 (68%) of 55 children. However, in 6 (3.9%) of them (aged 10-15 years), cardiac rhabdomyomas were noted to either grow (3 cases) or appear de novo (3 cases), such that the frequency of cardiac rhabdomyomas in adolescents was 6 (54%) of 11. Most (61%) tumors were clinically silent. Clinical manifestations included heart failure (5.4%), arrhythmias (23%), and murmurs (14.9%). One child died as a result of cardiac insufficiency. Cardiac rhabdomyomas were more frequent in theTSC2 (54%) than TSC1 (20%) groups. CONCLUSIONS. Cardiac rhabdomyomas are seen in the majority of young children with tuberous sclerosis complex. Most produce no clinical consequences and will spontaneously regress. However, during puberty, cardiac rhabdomyomas may enlarge or appear de novo; thus, attention should be paid to potential clinical signs and monitoring by echocardiography should be performed. Cardiac rhabdomyomas were observed more often in the TSC2 group.

Tuberous sclerosis (TSC) is an autosomal dominant disorder caused by mutations in either of two genes, TSC1 and TSC2. Point mutations and small indels account for most TSC1 and TSC2 mutations. We examined 261 TSC DNA samples (209 small-mutation-negative and 52 unscreened) for large deletion/duplication mutations using multiplex ligation-dependent probe amplification (MLPA) probe sets designed to permit interrogation of all TSC1/2 exons, as well as 15–50 kb of flanking sequence. Large deletion/duplication mutations in TSC1 and TSC2 were identified in 54 patients, of which 50 were in TSC2, and 4 were in TSC1. All but two mutations were deletions. Only 13 deletions were intragenic in TSC2, and one in TSC1, so that 39 (73%) deletions extended beyond the 5′, 3′ or both ends of TSC1 or TSC2. Mutations were identified in 24% of small-mutation-negative and 8% of unscreened samples. Eight of 54 (15%) mutations were mosaic, affecting 34–62% of cells. All intragenic mutations were confirmed by LR-PCR. Genotype/phenotype analysis showed that all (21 of 21) patients with TSC2 deletions extending 3′ into the PKD1 gene had kidney cysts. Breakpoints of intragenic deletions were randomly distributed along the TSC2 sequence, and did not preferentially involve repeat sequence elements. Our own 20-plex probe sets gave more robust performance than the 40-plex probe sets from MRC-Holland. We conclude that large deletions in TSC1 and TSC2 account for about 0.5 and 6% of mutations seen in TSC patients, respectively, and MLPA is a highly sensitive and accurate detection method, including for mosaicism.

Tuberous sclerosis complex (TSC) is an autosomal, dominantly inherited neurocutaneous syndrome characterized by a wide range of neurological abnormalities, tumors of different organs, and variable clinical symtomatology and severity. TSC is caused by mutations in either of two tumor suppressor genes: TSC1 or TSC2. The aim of this study was to analyze the clinical picture of TSC in patients with an identical TSC2 mutation. We tried to discover to what extent we may expect variability in the clinical set of symptoms in patients with identical mutation of TSC2 gene.Mutations were identified in 100 of 170 cases. There were only 4 patients with the same type of TSC2 mutation: 5238-5255 del 18bp, del 1746 HIKRLR. Their ages were 1.5, 9, 9, and 10 years. A standardized clinical assessment of TSC symptoms was used.Epilepsy, depigmented spots, and periventricular calcification and cortical tubers were diagnosed in all the 4 patients, cardiac rhabdomyoma and angiomyolipoma of the kidneys in 3, and mental retardation and forehead fibroma in 2. Other symptoms occurred rarely or were absent. There was variability in TSC symptoms in patients with the identical type of TSC2 mutation. The main symptoms were present in all or in the majority of patients. Clinical picture also differed with the age of patient.There are many influencing factors contributing to the diversity of the clinical picture and pathology of TSC. Obviously, a greater number of cases are needed for further analysis and more precise conclusions.

We report a child in whom multiple cardiac rhabdomyomas were identified on routine fetal ultrasonography. Molecular genetic studies identified the TSC2 gene missense mutation (E36; 4672 G>A, 1558 E>K TSC2). Both general and neurodevelopment of the patient have been normal. When last examined at age 6 years, he had no skin manifestations of tuberous sclerosis complex. Computed tomography of the brain revealed two periventricular calcifications consistent with the molecular diagnosis. This is the first report of molecularly confirmed tuberous sclerosis complex in a child with multiple cardiac rhabdomyomas and no other clinical manifestations of the disease. We propose that all cases of multiple cardiac rhabdomyomas in an infant be given a tentative diagnosis of tuberous sclerosis complex. ( J Child Neurol 2005;20:988—989).

Cardiac rhabdomyoma (CR) is the most common heart tumor in children and is usually associated with tuberous sclerosis complex (TSC). Tuberous sclerosis complex is a genetic disorder caused by a mutation in either of 2 genes (TSC1 or TSC2) and characterized by the formation of hamartomas in multiple organs. The 2 TSC proteins, hamartin and tuberin, antagonize the mammalian target of rapamycin (mTOR) signaling pathway, thus regulating cell growth and proliferation. Recently, some trials treating TSC with the mTOR inhibitor rapamycin have been published; however, the impact of such treatment on heart tumors is not known. The aim of the present paper was to study the molecular pathobiology of CRs. Six CR samples were studied. The expression of S6K1, pErk, Erk, Akt, pAkt, 4E-BP1, hamartin, tuberin, mTOR, bcl-2, Bax, and Ki-67 was examined using immunohistochemistry and Western blot methods. Increased expression of Bax, mTOR, pS6K, pErk, and 4E-BP1 was found in all CR samples. Hamartin and tuberin expression was decreased in tumors versus normal heart tissues. This is the first study showing mTOR pathway dysregulation and an increased expression of proapoptotic Bax protein in CRs associated with TSC.

Tuberous sclerosis (TSC) is a relatively common hamartoma syndrome caused by mutations in either of two genes, TSC1 and TSC2. Here we report comprehensive mutation analysis in 224 index patients with TSC and correlate mutation findings with clinical features. Denaturing high-performance liquid chromatography, long-range polymerase chain reaction (PCR), and quantitative PCR were used for mutation detection. Mutations were identified in 186 (83%) of 224 of cases, comprising 138 small TSC2 mutations, 20 large TSC2 mutations, and 28 small TSC1 mutations. A standardized clinical assessment instrument covering 16 TSC manifestations was used. Sporadic patients with TSC1 mutations had, on average, milder disease in comparison with patients with TSC2 mutations, despite being of similar age. They had a lower frequency of seizures and moderate-to-severe mental retardation, fewer subependymal nodules and cortical tubers, less-severe kidney involvement, no retinal hamartomas, and less-severe facial angiofibroma. Patients in whom no mutation was found also had disease that was milder, on average, than that in patients with TSC2 mutations and was somewhat distinct from patients with TSC1 mutations. Although there was overlap in the spectrum of many clinical features of patients with TSC1 versus TSC2 mutations, some features (grade 2–4 kidney cysts or angiomyolipomas, forehead plaques, retinal hamartomas, and liver angiomyolipomas) were very rare or not seen at all in TSC1 patients. Thus both germline and somatic mutations appear to be less common in TSC1 than in TSC2. The reduced severity of disease in patients without defined mutations suggests that many of these patients are mosaic for a TSC2 mutation and/or have TSC because of mutations in an as-yet-unidentified locus with a relatively mild clinical phenotype.