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Objective: To investigate whether mammalian target of rapamycin inhibitor everolimus can improve intellectual disability, autism, and other neuropsychological deficits in children with tuberous sclerosis complex (TSC)., Methods: In this 12-month, randomized, double-blind, placebo-controlled trial, we attempted to enroll 60 children with TSC and IQ <80, learning disability, special schooling, or autism, aged 4-17 years, without intractable seizures to be assigned to receive everolimus or placebo. Everolimus was titrated to blood trough levels of 5-10 ng/mL. Primary outcome was full-scale IQ; secondary outcomes included autism, neuropsychological functioning, and behavioral problems., Results: Thirty-two children with TSC were randomized. Intention-to-treat analysis showed no benefit of everolimus on full-scale IQ (treatment effect -5.6 IQ points, 95% confidence interval -12.3 to 1.0). No effect was found on secondary outcomes, including autism and neuropsychological functioning, and questionnaires examining behavioral problems, social functioning, communication skills, executive functioning, sleep, quality of life, and sensory processing. All patients had adverse events. Two patients on everolimus and 2 patients on placebo discontinued treatment due to adverse events., Conclusions: Everolimus did not improve cognitive functioning, autism, or neuropsychological deficits in children with TSC. The use of everolimus in children with TSC with the aim of improving cognitive function and behavior should not be encouraged in this age group., Clinicaltrialsgov Identifier: NCT01730209., Classification of Evidence: This study provides Class I evidence that for children with TSC, everolimus does not improve intellectual disability, autism, behavioral problems, or other neuropsychological deficits., (© 2019 American Academy of Neurology.)

Most patients with tuberous sclerosis complex (TSC) suffer from epilepsy, and many have cognitive and behavioral problems like severe intellectual disability, autism, and hyperactivity. Only rare patients with TSC and autism have a normal intelligence quotient. We report a 13-year-old girl with definite TSC who had early-onset severe epilepsy, autistic behavior, and moderate developmental delay. By school age, however, she had normal intelligence; her intelligence quotient was at least 70 based on a Stanford-Binet test that she refused to complete. She showed good reading, writing, and language comprehension skills, and the special abilities of hyperlexia, hypermnesia, and hypercalculia. However, she did not speak. Criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, and her Childhood Autism Rating Scale score of 36 indicated mild to moderate autism. She had severe electroencephalographic abnormalities: hypsarrhythmia, multifocal or generalized epileptiform discharges, and electrical status epilepticus during sleep, with a continuous left temporal focus. Magnetic resonance imaging showed many cortical tubers in all brain lobes, and subependymal nodules. We discuss possible explanations for her lack of speech. Considered as speech apraxia, her mutism could be either a symptom of her TSC or a component of her autism. Another possibility is that long-lasting electrical status epilepticus during sleep led to her autistic behavior and language arrest. Still another possibility is that a disinhibited mammalian target of rapamycin (mTOR) pathway was at the root of all of her neuropsychiatric symptoms.

Tuberous sclerosis (TSC) is an autosomally dominant neurocutaneous disease notable for its high comorbidity with autism in human patients. Studies of murine models of tuberous sclerosis have found defects in cognition and learning, but thus far have not uncovered deficits in social behaviors relevant to autism. To explore social communication and interaction in TSC2 heterozygous mice, we recorded ultrasonic vocalizations (USV) and found that although both wild-type (WT) and heterozygous pups born to WT dams showed similar call rates and patterns, baseline vocalization rates were elevated in pups born to heterozygous dams. Further analysis revealed several robust features of maternal potentiation in all but WT pups born to heterozygous dams. This lack of potentiation is suggestive of defects in mother-pup social interaction during or before the reunion period between WT pups and heterozygous dams. Intriguingly, male pups of both genotypes born to heterozygous dams showed particularly heightened call rates and burst patterns. Because our maternal retrieval experiments revealed that TSC2(+/-) dams exhibited improved defensive reactions against intruders and highly efficient pup retrieval performance, the alterations in their pups' USVs and maternal potentiation do not appear to result from poor maternal care. These findings suggest that a pup's interaction with its mother strongly influences the pup's vocal communication, revealing an intriguing dependence of this social behavior on TSC2 gene dosage of both parties involved. Our study of this murine model thus uncovers social abnormalities that arise from TSC haploinsufficiency and are suggestive of autism.

Tuberous sclerosis complex is a multisystem disorder in which neurologic problems cause the greatest disability. High rates of mental retardation and autism spectrum disorders are associated with the diagnosis. Early-onset seizures and increased tuber burden are risk factors for cognitive impairment. Early-onset seizures, particularly infantile spasms, are risk factors for autism. Tubers within the temporal lobe and cerebellum are often mentioned as risk factors for autism, although the findings are inconsistent. Seizure control is important for developmental outcome and quality of life. Early behavioral assessment and therapeutic intervention, as well as seizure control, are the most effective means of promoting neurodevelopmental outcome.

Tuberous sclerosis is often associated with developmental and behavioural disorders including typical or partial autistic syndrome. However, it may be difficult to recognize tuberous sclerosis behind an infantile autism during the early stages of the disease. Therefore, tuberous sclerosis must be regularly looked for on the basis of its major and minor criteria in any cases of infantile autism. The child psychiatrist is preferentially involved in the management of the various aspects of this association, ie, behavioural or character disorders, difficulties in social relationships and communication, mental retardation, feeding disorders, and psychological consequences for the families. The support provided may be complemented by that offered by the Association for Bourneville's tuberous sclerosis.

Fifty-nine cases with infantile autism/autistic disorder were subclassified according to associated medical condition (fragile-X, tuberous sclerosis, neurofibromatosis, hypo-melanosis of Ito, Moebius syndrome, Rett syndrome, and a 'new' syndrome associated with a marker chromosome). It was concluded that, even within a group of cases fitting currently accepted criteria for autism, there is considerable variation in symptom profile depending on the exact type of associated medical condition.

Two behavior genetic research strategies have been utilized to understand gene influences in autism. There is overwhelming evidence for gene involvement, although an exact mode of inheritance has not yet been elucidated. Family and twin studies illustrate that the clinical phenotype of autism is not sufficient to characterize the underlying genotype(s) involved. Exactly what should be included in the phenotype remains elusive. Cognitive and social deficits are indicated as milder variants of the autism phenotype, but precisely how to define these deficits requires further research. Furthermore, more complex models of inheritance (e.g., two-locus models--multifactorial and major gene) may be necessary to explain gene influences in autism. Genetic heterogeneity is indicated in autism, with an X-linked disorder, fragile X, and an autosomal dominant disorder, tuberous sclerosis, together accounting for perhaps 8% to 11% or more of cases of autism. Differences in family patterns (i.e., recurrence risks) of neuropsychiatric disorders between autism with and without mental retardation or other clinically defined groups (e.g., males and females) are suggested. Whether these differences represent genetic heterogeneity or multifactorial inheritance with varying thresholds (e.g., of severity or sex differences) cannot be distinguished on the basis of the data available to date. Autosomal recessive inheritance is suggested in a subgroup of families with autism, but the proportion of all autism that may be accounted for by autosomal recessive inheritance is unknown. Evidence exists that stoppage occurs in families with autism, however, and this can affect accurate estimates of segregation ratios when not taken into account. Future family studies need to report (1) exact ascertainment schemes and specification of probands and (2) sex and birth order of affected siblings, including sibship size, so that data may be pooled and such effects can be tested. Investigations of populations with fragile X or tuberous sclerosis as well as those with autism (without known genetic disorders) will identify the etiologic basis of these associations. Such associations may be due to linkage of genes underlying autism and those underlying the known genetic disorders (i.e., linkage disequilibrium) or shared brain pathophysiology or merely shared overt behaviors. Until such mechanisms are elucidated, we can use only empiric risk figures in genetic counseling situations of autism, assuming that no known genetic or environmental cause is identified. Pooling available data from family and twin studies, the following empiric risks are suggested for genetic counseling purposes. An average sibling risk (frequency of affected siblings among all siblings) based on pooled data is 3% (i.e., 57/1698).(ABSTRACT TRUNCATED AT 400 WORDS)

A patient with evidence of both infantile autism and tuberous sclerosis syndrome is presented. A possible relationship between the 2 syndromes is discussed. Examination of the skin of young, very disturbed children is recommended.