Definition

Autism represents a spectrum of complex brain disorders resulting in social, behavioral, and communication problems. Other conditions that are part of this spectrum include Asperger syndrome and pervasive developmental disorder. In the US, autism spectrum disorders affect about 1 in 100 children aged 3-17 years old.

Causes

Autism is a neurodevelopmental disorder. This means that problems in brain development cause autism. Scientists are searching for answers about what causes these development problems. Studies suggest:

• Autism seems to run in some families. Several genes may be involved.
• Problems during pregnancy or delivery may interfere with normal brain development.
• Something in the environment that a child is exposed to may be a factor.

Risk Factors

These factors increase your chance of developing autism:

• Sex: male (Boys are four times more likely to have autism than girls.)
• Family history: siblings of a child with autism have a 3%-7% chance of being autistic.
• A number of other conditions are associated with autism, although the relationship between them is not clear:
  • Neurofibromatosis
  • Tuberous sclerosis
  • Fragile X syndrome
  • Phenylketonuria (PKU)
  • Möbius syndrome
  • Epilepsy
  • Herpes encephalitis
  • Cytomegalovirus
  • Problems during pregnancy or delivery
  • Contracting rubella during pregnancy (a risk for the child)
• Having parents who are older

The Conditions Above Primarily Affect the Central Nervous System

© 2011 Nucleus Medical Media, Inc.

Symptoms

Autism usually first appears during early childhood (2-6 years old). The severity of symptoms varies over a wide spectrum. Behaviors and abilities may differ from day to day; symptoms may decrease as the child grows older. Children with autism may exhibit a combination of abnormal behaviors.

Symptoms include:

• Avoiding social contact
• Having problems with language (loss of language)
• Using words incorrectly, changing the meaning of a common word
• Gesturing frequently
• Avoiding eye contact
• Having trouble with nonverbal communication
• Lacking interest in normal activities for that age
• Spending a lot of time alone
• Not playing imaginatively
• Not starting pretend games
• Not imitating others
• Having sensitivity to sound, smell, taste, sights, and touch
• Responding to stimulation in an abnormal way
• Not reacting to smiles in the manner expected
• Being hyperactive
• Being passive
• Having tantrums
• Being single-minded
• Being aggressive
• Hurting self (self-mutilation)
• Engaging in repetitive movement, such as rocking or flapping a hand
• Resisting change
• Forming odd attachments to objects
• Sniffing or licking of toys
• Not understanding other peoples' feelings and needs
• Having constipation and being a picky eater

Some people with autism suffer from other disorders as well, including:

• Seizures
• Intellectual disability
• Genetic disorders, such as fragile X syndrome

Diagnosis

Doctors who specialize in autism will observe the child's behavior, social contacts, and communication abilities. They will assess mental and social development and ask parents about the child's behavior. Some doctors ask parents to bring in videos of the child at home.

Tests may include:

• Neuropsychological tests
• Questionnaires and observation schedules
• Intelligence tests

Medical tests to rule out other conditions that cause similar symptoms may include:

• Blood tests
• Urine tests
• DNA testing
• Electroencephalogram (EEG) —a test that records the brain's activity by measuring electrical currents through the brain

Treatment

There is no cure for autism. The severity of symptoms may decrease over the years. But the condition lasts for life. Children with autism and their families may benefit from early intervention. For instance, children aged 18-30 months who participate in high-intensity intervention targeting developmental behavior, showed improvements in their IQ, language, and adaptive behavior.

Children with autism respond well to a structured, predictable schedule. With help, many children with autism learn to cope with their disabilities. Most need assistance and support throughout their lives. Others are able to work and live independently when they grow up.

Interventions to help children with autism include:

Prevention

There are no guidelines for preventing autism because the cause is unknown. Scientists are searching for its underlying causes.