Autism Spectrum Disorder Symptoms, Treatment, Tests, Types, Causes

Facts you should know about autism

Impaired development in communication, behavior, and social interaction characterize autism.

Autism and related disorders are now referred to as autism spectrum disorders.
Characteristics of autism include impaired development in social interaction, communication, and behavior.
The degree of autism varies from mild to severe.
Severely afflicted persons with autism can appear to have a profound intellectual disability. Research tends to continue to refute the idea that immunizations cause autism.
The cause of autism is unknown.
The optimal treatment of autism involves an educational or vocational program that is suited to the developmental level of the child or adult, respectively.
It is important for the unique medical and mental-health needs of people with autism to be addressed in order to optimize both their life expectancy and quality of life.
Persons with autism and those who care for them often engage in advocacy activities like the walk for autism during April, which is Autism Awareness Month.

What is autism?

Autism is a developmental disorder that is characterized by impaired development in communication, social interaction, and behavior. It affects the lives of many children and their families. It tends to affect more boys than girls.

In the past, autism has been confused with childhood schizophrenia or childhood psychosis, and may have been misunderstood as schizotypal personality disorder in some adults. As additional research information about autism becomes available, the scope and definition of the condition continues to become more refined. Some of the past confusion about the disorder has been resolved.

Learn the early red flags, warning signs, and symptoms of autism.

Autism Symptoms and Screening

It is commonplace to have a family member or close friend with a child
diagnosed with one of the autism spectrum disorders (ASDs, including
autistic
disorder, Asperger disorder,
pervasive developmental disorder). These are a set
of neurodevelopmental disabilities affecting young children and adults, which
are currently not considered “curable.” The goals of management include
minimizing the symptoms and maximizing both independent function and quality of
life. These are not uncommon disorders. Their prevalence has been estimated as
approximately 6.5 per 1000 children, or 1 in every 150 children. Many believe
that there is an “Autism Epidemic.” However, as with many diseases and
disorders, there are many reasons for this high prevalence.

Fortunately, significant media coverage and increased research have resulted
in a better educated public and more vigilant healthcare practitioners. It is
clear that early diagnosis and intervention are associated with better outcomes.

Learn more about autism signs, symptoms, and screening »

What are early signs and symptoms of autism in children and adults?

The current Diagnosis and Statistical Manual of Mental Disorders, fifth edition (DSM-V) identifies two features that are associated with autism:

impairment in social interaction and communication, and
repetitive unusual behavior patterns (stereotypical behavioral patterns).

What are the different types of autism?

The group of disorders that formerly included autism, pervasive developmental disorder, not otherwise specified (PDD-NOS), Asperger's syndrome, and sometimes Rett disorder and childhood integrative disorder are now referred to as autism spectrum disorders. The range of these disorders varies from severely impaired individuals that were formerly described as suffering from autism to other, more high-functioning individuals who have abnormalities of social interaction but normal intelligence, who were described as having Asperger's syndrome. The ways in which autism spectrum disorders are exhibited can differ greatly. Additionally, autism can be found in association with other disorders such as mental retardation and certain medical conditions. The degree of autism can range from mild to severe. Mildly affected individuals may appear very close to normal. Severely afflicted individuals may have an extreme intellectual disability and be unable to function in almost any setting.

What causes autism?

Since autism was first added to the psychiatric literature about 50 years ago, there have been numerous studies and theories about its causes. Researchers still have not reached agreement regarding its specific causes. First, it must be recognized that autism is a set of a wide variety of symptoms and may have many causes. This concept is not unusual in medicine. For instance, the set of symptoms that we perceive of as a "cold" can be caused by literally hundreds of different viruses, bacteria, and even our own immune system.

Autism is thought to be a biologically-based disorder. In the past, some researchers had suggested that autism was the result of poor attachment skills on the part of the mother. This belief has caused a great deal of unnecessary pain and guilt on the part of the parents of children with autism, when in fact, the inability of the individual with autism to interact appropriately is one of the key symptoms of this developmental disorder. Some risk factors for autism include high maternal and paternal age (more than 35 years of age) at the time of birth of the child, as well as maternal prenatal medication use, bleeding, or gestational diabetes. Other support of a biological theory of autism includes that several known neurological disorders are associated with autistic features. Autism is one of the symptoms of these disorders. These conditions include:

tuberous sclerosis and the fragile X syndrome (inherited disorder);
cerebral dysgenesis (abnormal development of the brain);
Rett syndrome (a mutation of a single gene); and
some of the inborn errors of metabolism (biochemical defects).

Autism, in short, seems to be the end result or "final common pathway" of numerous disorders that affect brain development. Also, brain studies have demonstrated that persons with autism tend to have a number of abnormalities in brain size. In general, however, when clinicians make the diagnosis of autism, they are excluding the known causes of autistic behaviors. However, as the knowledge of conditions that cause autism advances, fewer and fewer cases will likely be thought of as being "pure" autism and more individuals will be identified as having autism due to specific causes.

There is a strong association between autism and seizures. This association works in two ways: First, many patients with autism develop seizures. Second, patients with seizures, which are probably due to other causes, may develop autistic-like behaviors. One special and often misunderstood association between autism and seizures is the Landau-Kleffner syndrome. This syndrome is also known as acquired epileptic aphasia. Some children with epilepsy develop a sudden loss of language skills — especially receptive language (the ability to understand). Many often also develop the symptoms of autism.

These children often, but not always, have a characteristic pattern of electrical brain activity seen on EEG (electroencephalogram) during deep sleep called electrographic status epilepticus during sleep (ESES). The usual age of onset of language loss or regression is around 4 years of age, which makes the Landau-Kleffner syndrome distinguishable from autism on these grounds, in that autism usually is first exhibited in younger children. However, in recent years, some children (very, very few) who did not exhibit overt (observable) seizures were found to have Landau-Kleffner syndrome.

The importance of these findings is that, although rare, the Landau-Kleffner syndrome can resolve spontaneously and, in some cases, can be treatable with prednisone, a steroid medication related to cortisone. This association between the Landau-Kleffner syndrome and autism has led many clinicians and families to search for the typical EEG pattern (ESES) in individuals with autism. This unusual EEG pattern is seen only in deep sleep, which usually requires prolonged recordings of up to 12 hours. Many children and adults with this disorder will display some abnormalities on their sleep EEG, but probably very few have true Landau-Kleffner syndrome that will respond to treatment.

It must also be noted that prednisone, in the very high doses used to treat Landau-Kleffner syndrome, almost invariably produces side effects, which may include weight gain, high blood pressure, diabetes, growth failure, stomach ulcers, irritability, mood swings, hyperactivity, destruction of the hip joint, and susceptibility to infectious disease (suppressed immune system). While most of these side effects are reversible, some of the complications of high-dose prednisone therapy can be irreversible and even fatal.

Other treatments ranging from common anticonvulsant therapy to surgery have been proposed and are being tried for Landau-Kleffner syndrome. It is difficult to evaluate the true effects of any treatment for Landau-Kleffner syndrome due to the high rate of spontaneous resolution of symptoms (remission).

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Is autism genetic?

Because many different disorders can result in autism, this question is complex. Certainly, disorders such as the fragile X syndrome and tuberous sclerosis, which are both associated with autism, are inherited. There are many families with more than one child with autism where the autism is not clearly due to another cause. Recent studies have found that the gene for at least one kind of familial autism may be on chromosome 13. In some families, autism seems to be passed from generation to generation. In other families, autism is not found in prior generations, but affects multiple siblings (brothers or sisters). The results of this research make it likely that at least one “autism gene” will eventually be found.

However, the majority of individuals with autism do NOT have a strong family history, which supports the premise that environmental or a combination of environmental and genetic factors contribute to the development of autism. In this context, environmental is meant to indicate any nongenetic factor, including infections, toxins, nutrition, or others.

QUESTION

Autism is a developmental disability.
See Answer

Impairment of social interaction and communication

Individuals with autism fail to develop normal personal interactions in virtually every setting. This means that affected persons fail to form the normal social contacts that are such an important part of human development. This impairment may be so severe that it even affects the bonding between a mother and an infant. It is important to note that, contrary to popular belief, many, if not most, persons with this disorder are capable of showing affection, demonstrating affection bonding with their mothers or other caregivers. However, the ways in which individuals with autism demonstrate affection and bonding may differ greatly from the ways in which others do so. Their limited socialization may erroneously lead family members and health professionals away from considering the diagnosis of autism.

As the child develops, interaction with others continues to be abnormal. Affected behaviors can include eye contact, facial expressions, and body postures. There is usually an inability to develop normal peer and sibling relationships and the child often seems isolated. There may be little or no joy or interest in normal age-appropriate activities. Affected children or adults do not seek out peers for play or other social interactions. In severe cases, they may not even be aware of the presence of other individuals.

Communication is usually severely impaired in persons with autism. What the individual understands (receptive language) as well as what is actually spoken by the individual (expressive language) are significantly delayed or nonexistent. Deficits in language comprehension include the inability to understand simple directions, questions, or commands. Persons with a high-functioning autism spectrum disorder might understand simple speech but still have difficulty interpreting the more subtle meaning in conversation. There may be an absence of dramatic or pretend play and these children may not be able to engage in simple age-appropriate childhood games such as Simon Says or Hide-and-Go-Seek. Teens and adults with autism may continue to engage in playing with games that are for young children and may seek to establish friendships with people much younger than them.

Individuals with autism who do speak may be unable to initiate or participate in a two-way conversation (reciprocal). Frequently the way in which a person with this disorder speaks is perceived as unusual. Their speech may seem to lack the normal emotion and sound flat or monotonous. The sentences are often very immature: “want water” instead of “I want some water, please.” Those with autism often repeat words or phrases that are spoken to them. For example, you might say, “Look at the airplane!” and the child or adult may respond “at airplane,” without any knowledge of what was said. This repetition is known as echolalia. Memorization and recitation of songs, stories, commercials, or even entire scripts is not uncommon. While many feel this is a sign of intelligence, the autistic person usually does not appear to understand any of the content in his or her speech.

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Behaviors

Persons with autism often exhibit a variety of abnormal behaviors. There may be repetitive actions, as well as hypersensitivity to sensory input through vision, hearing, or touch (tactile). As a result, there may be an extreme intolerance to loud noises or crowds, visual stimulation, or things that are felt. Birthday parties and other celebrations can be disastrous for some of these individuals. Wearing socks or tags on clothing may be perceived as painful. Sticky fingers, playing with modeling clay, eating birthday cake or other foods, or walking barefoot across the grass can be unbearable. On the other hand, there may be an underdeveloped (hyposensitivity) response to the same type of stimulation. This individual may use abnormal means to experience visual, auditory, or tactile (touch) input. This person may head bang, scratch until blood is drawn, scream instead of speaking in a normal tone, or bring everything into close visual range. He or she might also touch an object, image, or other people thoroughly just to experience the sensory input.

Children and adults who have autism are often tied to routine and many everyday tasks may be ritualistic. Something as simple as a bath might only be accomplished after the precise amount of water is in the tub, the temperature is exact, the same soap is in its assigned spot, and even the same towel is in the same place. Any break in the routine can provoke a severe reaction in the individual and place a tremendous strain on the adult trying to work with him or her.

There may also be nonpurposeful repetition of actions or behaviors. Persistent rocking, teeth grinding, hair or finger twirling, hand flapping, and walking on tiptoe are not uncommon. Frequently, there is a preoccupation with a very limited interest or a specific plaything. A child or adult may continually play with only one type of toy. The child may line up all the dolls or cars and the adult line up their clothes or toiletries, for example, and repeatedly and systematically perform the same action on each one. Any attempt to disrupt the person may result in extreme reactions on the part of the individual with autism, including tantrums or direct physical attack. Objects that spin, open and close, or perform some other action can hold an extreme fascination. If left alone, a person with this disorder may sit for hours turning off and on a light switch, twirling a spinning toy, or stacking nesting objects. Some individuals can also have an inappropriate bonding to specific objects and become hysterical without that piece of string, paper clip, or wad of paper.

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How do doctors diagnose autism in children and adults?

The essential features of autism are the significantly impaired or abnormal development of communication and social interaction and the abnormally restricted repertoire of behaviors, activities, and interests. This disturbance in normal development must manifest itself by the time the child is a toddler, prior to age 3. While many parents report normal development in the first year of the child, there is actually limited opportunity to observe this, as the child is often not brought to the attention of a practitioner who has specific experience in diagnosing autism until several years later in many cases. If there is a period of normal development, it cannot extend past age 3. As the early onset of the disorder is a key component in its diagnosis, it is important that practitioners screen for the possible presence of autism in all children from infancy on. As identifying autism as early as possible allows more timely and, therefore, more effective treatment, professionals tend to screen infants and toddlers using a variety of questionnaires, tests, and checklists. Examples of such screening tools include the Checklist for Autism in Toddlers, the Modified Checklist for Autism in Toddlers (M-CHAT), the Pervasive Developmental Disorders Screening Test, Second Edition, and the Screening Tool for Autism in Two-Year-Olds.

Any person with a delay or regression (loss) of language or an abnormality of social interaction beginning prior to the age of 3 may be suspected of being autistic. The medical evaluation begins with a thorough medical history and physical examination. This examination should be performed by a health care professional not only familiar with autism, but with other disorders that may appear similar to or mimic the symptoms of autism. The health care professional should have particular expertise in the neurological examination of impaired individuals or recommend consultation with such a professional, as subtle findings may lead the examiner down a particular diagnostic path. For example, the presence of mild weakness or increased reflexes on one side of the body will lead the examiner to conclude that a structural abnormality in the brain is present and that an MRI examination of the brain is appropriate.

The history and physical examination will point the examiner to specific diagnostic testing to evaluate for other conditions associated with autism or developmental delay. Any child who has a language delay should have his or her hearing formally evaluated. For example, it is not sufficient to simply determine whether or not a person being examined is able to hear. In order for normal language development to proceed, the individual must have sufficient hearing capabilities at low volumes in the high frequency range. Therefore, even if the person turns his or her head to a clap or shout, he or she may still have enough of a hearing deficit to inhibit language development.

There are two types of hearing tests; 1) behavioral audiometry; and 2) brainstem auditory evoked responses (BAER).

Behavioral audiometry is performed by a skilled clinical audiologist. The person being examined is placed in a room and his or her responses to different tones are observed.
For the brainstem auditory evoked responses (BAER) test, the individual is sedated and earphones are placed over the ears. Tones of different volumes and frequencies are played and the electrical response of the brain is monitored.

If he or she is capable, behavioral audiometry is the preferred method primarily because sedation is not required. Depending upon specific features of the examination and history, the practitioner may want to obtain blood and urine samples for specialized testing to evaluate for some of the inborn errors of metabolism and to obtain DNA for chromosomal studies and fragile X testing.

If the neurological examination is normal, there may be no need for a brain CT scan or MRI scan. However, if the neurological examination is suggestive of a structural brain lesion, then a neuroimaging study, preferably an MRI, should be performed. Newer imaging procedures such as SPECT or PET scans are used primarily as research tools and have no place in the initial evaluation of the autistic individual. In very specialized instances, such as the autistic person with difficult-to-control seizures, such tests may be useful.

The evaluation of individuals with autism by speech pathologists will provide not only detailed information as to the nature of the language deficits incurred by the afflicted individual, but will also be the first step in formulating a specific treatment plan with respect to language. Occupational assessment may be particularly helpful in determining the day-to-day strengths and vulnerabilities of the individual with autism (for example, sensitivity to clothing and food texture) and assist those who care for the person in promoting his or her strengths and compensating for their challenges.

Given the complex and far-reaching symptoms and effects of autism, it is generally thought that the most accurate and thorough diagnosis of this disorder is obtained by a group of health care professionals from various disciplines, also called a multidisciplinary team, that includes a pediatrician, speech and occupational therapists, educators, and often psychiatrists and others.

What are treatments for autism in children and adults?

Misinformation about autism is very common. Claims of a cure for autism are constantly presented to families of individuals with autism. There are various treatment models found within both the educational and clinical settings.

What common sociobehavioral interventions treat autism?

There is only one treatment approach that has prevailed over time and is effective for all persons, with or without autism. That treatment model is an educational (school or vocational) program that is suitable to a student's developmental level of performance. One such program is the Son-Rise Program. For adults, that treatment model refers to a vocational program that is suitable to the individual's developmental level of functioning.

Under the federal law, the Individuals with Disabilities Educational Act (IDEA) Act of 1990, students with a handicap are guaranteed an "appropriate education" in the Least Restrictive Environment (LRE), which is generally considered to be as normal an educational setting as possible. As a result of this legislation, children with autism have often been placed in a mainstreamed classroom and pulled out for whatever supplementary services were needed. Depending on the child's needs, he or she could be placed up to 100% of the school day in a mainstreamed or a special education setting or any combination of the two in order to receive the most appropriate help possible.

There is an increasing trend, however, in advocacy for children with autism, to segregate these children into small, highly structured and controlled academic and vocational training programs that are almost free from auditory and visual stimulation. All instruction is broken down into manageable segments. Information is presented in tiny units and the child's response is immediately sought. A classic stimulus-response approach is used to maximize learning. Each unit of information is mastered before another is presented. A fundamental behavior such as putting hands on the tabletop, for example, must be mastered before the child is required to perform any other tasks, or before more information is presented. The long-term effects of this type of treatment, as well as the ability of the child to transfer this to a broader context, continue to be evaluated. For people with autism whose symptoms include self-injurious behaviors, the focus of treatment has shifted from restriction and punishment to more of a focus on understanding potential motivators for negative behaviors, as well as rewards and other encouragement and support for using appropriate behaviors.

Children, teens, and adults with autism need to be taught how to communicate and interact with others. This is not a simple task, and it involves the entire family as well as other professionals. Parents of a child or adult with autism must continually educate themselves about new therapies and keep an open mind. Some treatments may be appropriate for some individuals but not for others. Many treatments have yet to be scientifically proven. Treatment decisions should always be made individually after a thorough assessment and based on what is suitable for that person and his or her family.

It is important to remember, despite some recent denials, that autism is usually a lifelong condition. The kind of support that is appropriate will change as the individual develops. Families must beware of treatment programs that give false hope of a cure. Acceptance of the condition in a family member is a very critical, foundational component of any treatment program and is understandably quite difficult.

Psychotherapeutic approaches that have been found to help improve functioning in some persons with autism include comprehensive behavioral therapy to address problematic behaviors. Social skills training and support are important in helping people with autism navigate interactions with others, since many of this population crave social interaction despite their limitations in engaging others socially. Cognitive behavioral treatment in verbal individuals with anxiety and voice output communication who are less verbal are considered promising areas of treatment as well.

Do vaccines play a role in autism?

Although some remain convinced that certain vaccines, vaccine preservatives, or medications taken to treat side effects of vaccines may cause autism, conventional wisdom is supported by research that continues to consistently demonstrate that immunizations do not cause autism.

What are the common medications used to treat the symptoms of autism?

Several medications have been tried or are being evaluated for the treatment of autism. No medication has consistently proven to be of benefit for either curing or comprehensively managing autism in closely controlled clinical trials.

In the past, a piece on a television news show prompted a great deal of interest in the hormone secretin as a treatment for autism. A child with autism with chronic gastrointestinal complaints showed dramatic improvement following some routine testing performed by a gastroenterologist during which a small dose of secretin was administered. The family and their physicians felt that the secretin may have resulted in the improvement in the symptoms of autism. Many physicians began prescribing secretin, which can be expensive. However, studies published appear to completely refute the claim that secretin treatment benefits autistic patients. This example underscores the importance of good clinical trials to determine whether a drug will help patients with autism before it is widely used.

Some medications have been found to help address some symptoms that may present in autism. For example, haloperidol (Haldol) and aripiprazole (Abilify) are thought to help treat aggression and methylphenidate has been determined to be helpful in addressing hyperactivity and other symptoms of attention deficit hyperactivity disorder (ADHD) in persons with autism. Risperidone (Risperdal) has been found to be quite helpful in many people whose autistic symptoms include odd, repetitive behaviors (stereotypies), hyperactivity, irritability, throwing tantrums, being aggressive towards others, and of injuring oneself.

Can diet and supplements play a role in the treatment of autism?

A number of dietary supplements are often given to persons with autism. Examples of such interventions include omega-3 fatty acids. While a significant percentage of people with autism are given dietary supplements as part of treatment, there is insufficient research to determine whether or not such interventions are helpful or harmful.

How does autism impact the family?

Having a family member with autism presents emotional, social, and financial challenges. The stress placed on parents and other family members of people with autism can be influenced by a number of factors. Examples of such factors include how well the person with autism functions, how much social support the family receives, and sometimes the ethnicity of the person’s parents. Siblings of children and teens with autism seem to fare better in their understanding and acceptance of the family member with autism when provided with education about their loved one’s condition.

What is the prognosis for children and adults with autism?

Persons with autism seem to have a higher mortality rate at younger ages compared to average individuals. This is particularly true for mortality that is related to seizures or infection. It is, therefore, important for the autistic population to receive good medical care from health care professionals who have knowledge and experience in addressing their unique medical needs.

Due to a number of potential factors, autistic persons tend to be vulnerable to nutritional problems. Specifically, factors like variations in appetite, refusal of many foods, food allergies, and side effects to some medications can disproportionately impact the food intake, and therefore, the nutritional status of this population. Individuals with autism have been found to be vulnerable to respiratory problems as well, which results in this population having more doctors' visits than people who do not have autism. As people with autism also are vulnerable to emotional struggles like anxiety, depression, and attention problems, the help of mental health professionals should be sought when appropriate.