Austism

Alternative Names

Pervasive developmental disorder - autism

Causes

Autism is a physical condition linked to abnormal biology and chemistry in the brain. The exact causes of these abnormalities remain unknown, but this is a very active area of research. There are probably a combination of factors that lead to autism.

Genetic factors seem to be important. For example, identical twins are much more likely than fraternal twins or siblings to both have autism. Similarly, language abnormalities are more common in relatives of autistic children. Chromosomal abnormalities and other nervous system (neurological) problems are also more common in families with autism.

A number of other possible causes have been suspected, but not proven. They involve:

• Diet
• Digestive tract changes
• Mercury poisoning
• The body's inability to properly use vitamins and minerals
• Vaccine sensitivity

The exact number of children with autism is not known. A report released by the U.S. Centers for Disease Control and Prevention (CDC) suggests that autism and related disorders are more common than previously thought, although it is unclear if this is due to an increasing rate of the illness or an increased ability to diagnose the illness.

Autism affects boys 3 - 4 times more often than girls. Family income, education, and lifestyle do not seem to affect the risk of autism.

Some parents have heard that the MMR vaccine that children receive may cause autism. This theory was based, in part, on two facts. First, the incidence of autism has increased steadily since around the same time the MMR vaccine was introduced. Second, children with the regressive form of autism (a type of autism that develops after a period of normal development) tend to start to show symptoms around the time the MMR vaccine is given. This is likely a coincidence due to the age of children at the time they receive this vaccine.

Several major studies have found NO connection between the vaccine and autism. The American Academy of Pediatrics and the Center for Disease Control and Prevention report that there is no proven link between autism and the MMR vaccine, or any other vaccine.

Some doctors believe the increased incidence in autism is due to newer definitions of autism. The term "autism" now includes a wider spectrum of children. For example, a child who is diagnosed with high-functioning autism today may have been thought to simply be odd or strange 30 years ago.

Symptoms

Most parents of autistic children suspect that something is wrong by the time the child is 18 months old and seek help by the time the child is 2. Children with autism typically have difficulties in:

• Pretend play
• Social interactions
• Verbal and nonverbal communication

Some children with autism appear normal before age 1 or 2 and then suddenly "regress" and lose language or social skills they had previously gained. This is called the regressive type of autism.

People with autism may:

• Be overly sensitive in sight, hearing, touch, smell, or taste (for example, they may refuse to wear "itchy" clothes and become distressed if they are forced to wear the clothes)
• Have unusual distress when routines are changed
• Perform repeated body movements
• Show unusual attachments to objects

The symptoms may vary from moderate to severe.

Communication:

• Cannot start or maintain a social conversation
• Communicates with gestures instead of words
• Develops language slowly or not at all
• Does not adjust gaze to look at objects that others are looking at
• Does not refer to self correctly (for example, says "you want water" when the child means "I want water")
• Does not point to direct others' attention to objects (occurs in the first 14 months of life)
• Repeats words or memorized passages, such as commercials
• Uses nonsense rhyming

Social interaction:

• Does not make friends
• Does not play interactive games
• Is withdrawn
• May not respond to eye contact or smiles, or may avoid eye contact
• May treat others as if they are objects
• Prefers to spend time alone, rather than with others
• Shows a lack of empathy

Response to sensory information:

• Does not startle at loud noises
• Has heightened or low senses of sight, hearing, touch, smell, or taste
• May find normal noises painful and hold hands over ears
• May withdraw from physical contact because it is overstimulating or overwhelming
• Rubs surfaces, mouths or licks objects
• Seems to have a heightened or low response to pain

Play:

• Doesn't imitate the actions of others
• Prefers solitary or ritualistic play
• Shows little pretend or imaginative play

Behaviors:

• "Acts up" with intense tantrums
• Gets stuck on a single topic or task (perseveration)
• Has a short attention span
• Has very narrow interests
• Is overactive or very passive
• Shows aggression to others or self
• Shows a strong need for sameness
• Uses repetitive body movements

feel free to get details:

http://health.nytimes.com/health/guides/disease/autism/overview.html