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Autism spectrum disorder: Clinical features

Marilyn Augustyn, MD
Section Editors
Marc C Patterson, MD, FRACP
Carolyn Bridgemohan, MD
Deputy Editor
Mary M Torchia, MD


Autism spectrum disorder (ASD) is a biologically based neurodevelopmental disorder characterized by impairments in two major domains: 1) deficits in social communication and social interaction and 2) restricted repetitive patterns of behavior, interests, and activities [1]. ASD encompasses disorders previously known as autistic disorder (classic autism, sometimes called early infantile autism, childhood autism, or Kanner's autism), childhood disintegrative disorder, pervasive developmental disorder-not otherwise specified, and Asperger disorder (also known as Asperger syndrome). (See "Autism spectrum disorder: Diagnosis", section on 'Diagnostic criteria' and "Asperger syndrome (a specific autism spectrum disorder): Clinical features and diagnosis in children and adolescents" and "Asperger syndrome (a specific autism spectrum disorder): Management and prognosis in children and adolescents".)

The clinical features of ASD will be reviewed here. Related topics are presented separately:

(See "Autism spectrum disorder: Surveillance and screening in primary care".)

(See "Autism spectrum disorder: Terminology, epidemiology, and pathogenesis".)

(See "Autism spectrum disorder: Diagnosis".)

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Literature review current through: Nov 2017. | This topic last updated: Mar 08, 2017.
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