Autism Spectrum Disorder: All You Want to Know

Autism spectrum disorder (ASD) refers to a group of complex neurodevelopment disorders that impacts a person’s social interaction and communication. Autism spectrum disorder became an umbrella diagnosis in the Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5) since 2013. Prior to that, a few conditions were considered separate, including autism, Asperger’s syndrome, childhood disintegrative disorder and an
unspecified form of pervasive developmental disorder.

Autism spectrum disorder has been a very common condition in the United States. According to CDC, about 1 in 59 children in all racial, ethnic, and socioeconomic groups has been identified with autism spectrum disorder.

Signs of autism usually appear by age 2 or 3, or even earlier, and often, it can be diagnosed as early as 18 months. Early intervention is usually critical as it may produce positive outcomes later in life.


Some children show signs of autism spectrum disorder in early infancy, while other children may develop normally for the first few months or years of life, and then suddenly lose skills they’ve already acquire.

Symptoms of autism spectrum disorder can vary greatly in behavior patterns and levels of severity — from low functioning to high functioning. Some children have difficulty learning language, some may have signs of lower than normal intelligence, and some others may have normal to high intelligence, some may be gifted. Research shows that almost half (44%) of children identified with ASD has average to above average intellectual ability. However, all of them have trouble communicating and adapting to social situations.

Children or adults with ASD might

  • not point at objects to show interest
  • not look at objects when another person points at them
  • avoid eye contact
  • prefer not to be held or cuddled, or might cuddle only when they want to
  • not respond to others when talked to, but respond to other sounds
  • be very interested in people, but not know how to talk, play, or relate to them
  • have trouble expressing their needs using typical words or motions
  • not play “pretend” games (for example, not pretend to “feed” a doll)
  • repeat actions over and over again
  • repeat or echo words, phrases or sentences said to them, but can’t talk in normal language
  • follow rigid routines and have trouble adapting when a routine changes
  • perform activities that could cause self-harm, such as biting or head-banging
  • have unusual reactions to the way things smell, taste, look, feel, or sound
  • lose skills they once had (for example, stop saying words they were using)


The cause of autism spectrum disorder is unknown. Research shows several factors can be involved.

  • Genetic Factors

Studies have shown that parents who have a child with ASD have a 2%–18% chance of having a second child who is also affected. Also among identical twins, if one child has ASD, then the other will be affected about 36-95% of the time, which is much higher than that in non-identical twins (0-31%).

ASD tends to occur more often in people who have certain genetic or chromosomal conditions. About 10% of children with autism are also identified as having Down syndrome, fragile X syndrome, tuberous sclerosis, or other genetic and chromosomal disorders.

  • Environmental Factors

Older parental age

Low birth weight

Exposure to the drug valproate in utero

Boys are about four times more likely to develop autism spectrum disorder than girls are.

  • Vaccines

There’s a controversy centering on whether a link exists between ASD and childhood vaccines. Despite extensive research, no reliable study has shown a link between autism spectrum disorder and any vaccines.


There’s no single medical test, like a blood test, to diagnose ASD. ASD is diagnosed by clinicians based on symptoms, signs, and testing according to the Diagnostic and Statistical Manual of Mental Disorders 5.

Diagnosing an ASD takes two steps:

  • Developmental Screening
  • Comprehensive Diagnostic Evaluation

All children should be screened for developmental delays during regular well-child doctor visits specifically at 18- and 24-month. During developmental screening the doctor might ask the parent some questions or talk and play with the child during an exam to see how the child learns, speaks, behaves, and moves.

Very early indicators that require evaluation by an expert include:

  • no babbling or pointing by age 1
  • no single words by age 16 months or two-word phrases by age 2
  • no response to name
  • loss of language or social skills previously acquired
  • poor eye contact
  • excessive lining up of toys or objects
  • no smiling or social responsiveness

If the doctor sees any signs of ASD, a comprehensive diagnostic evaluation is needed. This thorough review requires a multidisciplinary team, including a psychologist, neurologist, psychiatrist, and therapist to observe the child’s behavior and development, and take hearing and vision screening, genetic testing, neurological testing, and other medical testing.

Research has shown that a diagnosis of autism at age 2 can be reliable, valid, and stable. Studies have shown that parents of children with ASD notice a developmental problem before their child’s first birthday. If you notice the problem on your child, do not hesitate to consult your pediatrician.


No cure exists for autism spectrum disorder. There’re treatment options to improve the ASD symptoms, though. The ideal treatment plan is composed of therapies and interventions that meet the specific needs of the individual. And research shows that early intervention treatment services can greatly improve a child’s development.

Early intervention services help children from birth to 3 years old (36 months) learn important skills – walk, talk, and interact with others.

  • Behavior and Communication Approaches

These approaches address the range of social, language and behavioral difficulties of ASD. A notable treatment approach for people with an ASD is called applied behavior analysis (ABA) that encourages positive behaviors and discourages negative behaviors in order to improve a variety of skills. Floortime is another well-known approach that focuses on emotional and relational development (feelings, and relationships with caregivers). It also focuses on how the child deals with sights, sounds, and smells. Others include speech therapy, occupational therapy, sensory integration therapy, and the picture exchange communication system.

  • Dietary Approaches

Many biomedical interventions call for changes in diet. However, the positive effect of dietary treatments is lack of scientific support; it may work for a few, but not for all.

Advocates of dietary therapy believe food allergies or lack of vitamins and minerals cause symptoms of ASD, and they call for removing certain types of foods from a child’s diet and using vitamin or mineral supplements.
Some parents feel that dietary changes make a difference in how their child acts or feels.

If you are thinking about changing your child’s diet, talk to the doctor first. Or talk with a nutritionist to be sure your child is getting important vitamins and minerals.

  • Medication

There are no medications that can cure ASD or even treat the main symptoms. But there are medications that can help some people with related symptoms. For example, medication might help manage high energy levels, inability to focus, depression, or seizures.

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Risk of In Utero Exposure to Valproate

* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.