BRIEF DESCRIPTION
Autism Spectrum Disorders (ASD's): Autism spectrum disorders are neurodevelopmental disorders currently defined by significant qualitative impairments in 3 developmental domains:
For reasons that are not yet understood, abnormalities in these 3 developmental domains tend to cluster together in affected individuals. All individuals with autism-spectrum disorders have behavioral evidence of qualitative abnormalities of social development in combination with qualitative abnormalities of communication and/or stereotyped repetitive interests and behaviors. (click here for DSM-IV criteria for autism) (Source: American: 2000.) What comes naturally to most children about socially relating to others, does not come naturally to children with autism-spectrum disorders.
Many individuals with autism and PDD-NOS also have developmental delays. Because developmental delays are not found in all individuals with these disorders, developmental delay is not required for a diagnosis of autism-spectrum disorders.
Affected individuals may have a variety of other cognitive, emotional, and behavioral problems. Because these associated problems are not present in all affected individuals, they are not part of the criteria for autism-spectrum disorders, though they occur frequently and are very important to recognize and treat.
There are many behaviors and deficits that relate to each of the three domains above. As children with ASD's mature, these characteristics can change but the diagnosis remains.
Autistic Disorder: An ASD in which there is significant impairment in all three domains with onset before 3 years of age. Alternative names are autism, infantile autism, primary autism. A subtype is "high-functioning autism". IQ in children with autism can range from profound mental retardation to superior intelligence and verbal ability can range from absent to articulate speech.
Asperger's Disorder: An ASD in which there is significant impairment in social interaction and range of interests and activities, similar to a child with autism but what distinguishes the child with Asperger's from one with autism?. Persons with Asperger's Disorder do not have delayed onset of language, but their communication is often impaired by an inability to read social cues, making socially inappropriate comments, or having a narrow focus of interest. Verbal IQ is generally greater than 70. An alternative name is Asperger's Syndrome.
Pervasive Developmental Disorder NOS (not otherwise specified): This diagnosis is currently ill-defined. It could apply to a child with the same qualitative deficits in social and communication development as a child who has autism, but who does not meet criteria for Autism or Asperger's Disorder due to age of onset or extent of impairment. They may meet criteria for autism in the social or communication domain and may show some impairment in the other of these two domains. It could also refer to a child with global developmental delay who demonstrates impairment in some but not all of the three developmental domains listed above. This must be viewed in the context of the child's developmental age. This disorder is also referred to as PDD NOS.
PREVALENCE:
Autism Spectrum Disorders (Autism, Asperger's, and PDD NOS): 27.5/10,000
Autism: 10/10,000
Asperger's Disorder: 2.5/10,000
Previously, the rate of autism was felt to be much lower (4/10,000). There is no clear explanation for the increase. This may reflect changes in the diagnostic criteria and an increased awareness of autism rather than a true increase in incidence. The increase in diagnosis of autism has occurred across the spectrum of intellectual ability. Asperger's Disorder is the most uncommon of the autism spectrum disorder with a prevalence of only one quarter that of autism. Many children thought to have Asperger's Disorder upon further evaluation are found to have high functioning autism.
AUTHORS:
Primary Authors: Janet Lainhart, MD and Deborah Bilder, MD (2004)
PAGE BIBLIOGRAPHY
American Psychiatric Association.
Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR (Text Revision).
4th edition (June 2000) ed. American Psychiatric Association; 2000. ISBN 0890420254
This information is courtesy of The Utah Medical Home Project Team
www.medhomeportal.org
Copyright 2007 Utah Autism Council