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Synonym(s) -
Prevalence >1 / 1000
Inheritance -
Age of onset Childhood
  • F84.0
  • C0004352
  • D001321
  • 10003805


Autism is a neurodevelopmental disorder characterized by deficiencies in social interactions and communication skills, as well as repetitive and stereotyped patterns of behaviour. Recent epidemiological data show that autism is a frequent disorder, observed in 1 child in 500. The cumulated prevalence of diseases belonging to the spectrum of autism (autism, Asperger syndrome (see this term) and pervasive developmental disorders not otherwise specified, PDD-NOS) has been estimated at 1/167. Autism is four times more frequent in boys than in girls. Developmental disorders usually appear before the age of three. Language is often delayed or absent. Affected subjects often show intellectual deficiency and seizures can occur in some patients. The study of familial cases and twins shows the strong involvement of genetic factors in autism. In 10-25% of the cases, autism is linked to identified genetic diseases, such as tuberous sclerosis or fragile X syndrome (see these terms), or to chromosomal abnormalities. However, in most cases, the aetiology remains unknown. Diagnosis is based on clinical examination and should be established by experienced professionals. It is based on the parents' recordings of their child's development as well as on the evaluation of the disorders. Potentially associated genetic diseases should be excluded (karyotype, investigation of fragile X...). When it first manifests, autism can be mistakenly taken for deafness, some kind of language impairment or intellectual deficiency. Autism is more frequent in families with one affected child than in the general population. When no precise genetic defect has been detected in the child, the recurrence risk is estimated at 5 -10%. There is no specific treatment. Management is mainly symptomatic and rehabilitational and must be tailored to the child's needs. Early educational intervention considerably improves the prognosis.

Expert reviewer(s)

  • Dr Catalina BETANCUR

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