Below are articles by the National Institute of Neurological Disorders and Stroke, National Institute of Health and the Mayo Clinic on signs and symptoms of Autism and how autism is diagnosed. I found all of them to be informative and while very similar they do have subtle differences which may be relevant to the reader.
National Institute of Neurological Disorders and Stroke
HOW IS AUTISM DIAGNOSED?
How is autism diagnosed?
Autism varies widely in its severity and symptoms and may go unrecognized, especially in mildly affected
children or when it is masked by more debilitating handicaps. Doctors rely on a core group of behaviors to
alert them to the possibility of a diagnosis of autism. These behaviors are:
* Impaired ability to make friends with peers
* Impaired ability to initiate or sustain a conversation with others
* Absence or impairment of imaginative and social play
* Stereotyped, repetitive, or unusual use of language
* Restricted patterns of interest that are abnormal in intensity or focus
* Preoccupation with certain objects or subjects
* Inflexible adherence to specific routines or rituals
Doctors will often use a questionnaire or other screening instrument to gather information about a child’s
development and behavior. Some screening instruments rely solely on parent observations; others rely
on a combination of parent and doctor observations. If screening instruments indicate the possibility of
autism, doctors will ask for a more comprehensive evaluation.
Autism is a complex disorder
A comprehensive evaluation requires a multidisciplinary team including a psychologist, neurologist,
psychiatrist, speech therapist, and other professionals who diagnose children with ASDs. The team
members will conduct a thorough neurological assessment and in-depth cognitive and language testing.
Because hearing problems can cause behaviors that could be mistaken for autism, children with delayed
speech development should also have their hearing tested. After a thorough evaluation, the team usually
meets with parents to explain the results of the evaluation and present the diagnosis.
Children with some symptoms of autism, but not enough to be diagnosed with classical autism, are often
diagnosed with PDD-NOS. Children with autistic behaviors but well-developed language skills are often
diagnosed with Asperger syndrome. Children who develop normally and then suddenly deteriorate
between the ages of 3 to 10 years and show marked autistic behaviors may be diagnosed with childhood
disintegrative disorder. Girls with autistic symptoms may be suffering from Rett syndrome, a sex-linked
genetic disorder characterized by social withdrawal, regressed language skills, and hand wringing.
National Institute of Health
HOW IS AUTISM DIAGNOSED?
Autism diagnoses are increasing world wide. Autistic children have difficulties with social interaction, problems with verbal and nonverbal communication, and repetitive behaviors or
narrow, obsessive interests. New York, Los Angeles, Chicago, Houston, Philadelphia, San Diego, Detroit, Dallas, Phoenix, San Antonio, San Jose, Baltimore, Indianapolis, San
Francisco, Jacksonville, Columbus, Milwaukee, Memphis, Washington, Boston, Seattle, St. Louis, Atlanta, Pittsburgh, Minneapolis, Miami, Tampa, London, Paris. Rome, Munich,
Moscow, Sydney, Tokyo, Bejing, Shanghai
This extract from the National Institute of Health article is divided into two parts; Possible Indicators of
Autism Spectrum Disorders and; The Diagnosis of Autism Spectrum Disorders
Possible Indicators of Autism Spectrum Disorders
• Does not babble, point, or make meaningful gestures by 1 year of age
• Does not speak one word by 16 months
• Does not combine two words by 2 years
• Does not respond to name
• Loses language or social skills
Some Other Indicators
• Poor eye contact
• Doesn't seem to know how to play with toys
• Excessively lines up toys or other objects
• Is attached to one particular toy or object
• Doesn't smile
• At times seems to be hearing impaired
Social Symptoms
From the start, typically developing infants are social beings. Early in life, they gaze at people, turn toward
voices, grasp a finger, and even smile.
In contrast, most children with ASD seem to have tremendous difficulty learning to engage in the give-and-
take of everyday human interaction. Even in the first few months of life, many do not interact and they
avoid eye contact. They seem indifferent to other people, and often seem to prefer being alone. They may
resist attention or passively accept hugs and cuddling. Later, they seldom seek comfort or respond to
parents' displays of anger or affection in a typical way. Research has suggested that although children
with ASD are attached to their parents, their expression of this attachment is unusual and difficult to
“read.” To parents, it may seem as if their child is not attached at all. Parents who looked forward to the
joys of cuddling, teaching, and playing with their child may feel crushed by this lack of the expected and
typical attachment behavior.
Children with ASD also are slower in learning to interpret what others are thinking and feeling. Subtle
social cues—whether a smile, a wink, or a grimace—may have little meaning. To a child who misses these
cues, “Come here” always means the same thing, whether the speaker is smiling and extending her arms
for a hug or frowning and planting her fists on her hips. Without the ability to interpret gestures and facial
expressions, the social world may seem bewildering. To compound the problem, people with ASD have
difficulty seeing things from another person's perspective. Most 5-year-olds understand that other people
have different information, feelings, and goals than they have. A person with ASD may lack such
understanding. This inability leaves them unable to predict or understand other people's actions.
Although not universal, it is common for people with ASD also to have difficulty regulating their emotions.
This can take the form of “immature” behavior such as crying in class or verbal outbursts that seem
inappropriate to those around them. The individual with ASD might also be disruptive and physically
aggressive at times, making social relationships still more difficult. They have a tendency to “lose control,”
particularly when they're in a strange or overwhelming environment, or when angry and frustrated. They
may at times break things, attack others, or hurt themselves. In their frustration, some bang their heads,
pull their hair, or bite their arms.
Communication Difficulties
By age 3, most children have passed predictable milestones on the path to learning language; one of the
earliest is babbling. By the first birthday, a typical toddler says words, turns when he hears his name,
points when he wants a toy, and when offered something distasteful, makes it clear that the answer is “no.”
Some children diagnosed with ASD remain mute throughout their lives. Some infants who later show signs
of ASD coo and babble during the first few months of life, but they soon stop. Others may be delayed,
developing language as late as age 5 to 9. Some children may learn to use communication systems such
as pictures or sign language.
Those who do speak often use language in unusual ways. They seem unable to combine words into
meaningful sentences. Some speak only single words, while others repeat the same phrase over and over.
Some ASD children parrot what they hear, a condition called echolalia. Although many children with no
ASD go through a stage where they repeat what they hear, it normally passes by the time they are 3.
Some children only mildly affected may exhibit slight delays in language, or even seem to have precocious
language and unusually large vocabularies, but have great difficulty in sustaining a conversation. The
“give and take” of normal conversation is hard for them, although they often carry on a monologue on a
favorite subject, giving no one else an opportunity to comment. Another difficulty is often the inability to
understand body language, tone of voice, or “phrases of speech.” They might interpret a sarcastic
expression such as “Oh, that's just great” as meaning it really IS great.
While it can be hard to understand what ASD children are saying, their body language is also difficult to
understand. Facial expressions, movements, and gestures rarely match what they are saying. Also, their
tone of voice fails to reflect their feelings. A high-pitched, sing-song, or flat, robot-like voice is common.
Some children with relatively good language skills speak like little adults, failing to pick up on the “kid-
speak” that is common in their peers.
Without meaningful gestures or the language to ask for things, people with ASD are at a loss to let others
know what they need. As a result, they may simply scream or grab what they want. Until they are taught
better ways to express their needs, ASD children do whatever they can to get through to others. As people
with ASD grow up, they can become increasingly aware of their difficulties in understanding others and in
being understood. As a result they may become anxious or depressed.
Repetitive Behaviors
Although children with ASD usually appear physically normal and have good muscle control, odd repetitive
motions may set them off from other children. These behaviors might be extreme and highly apparent or
more subtle. Some children and older individuals spend a lot of time repeatedly flapping their arms or
walking on their toes. Some suddenly freeze in position.
As children, they might spend hours lining up their cars and trains in a certain way, rather than using them
for pretend play. If someone accidentally moves one of the toys, the child may be tremendously upset.
ASD children need, and demand, absolute consistency in their environment. A slight change in any
routine—in mealtimes, dressing, taking a bath, going to school at a certain time and by the same route—
can be extremely disturbing. Perhaps order and sameness lend some stability in a world of confusion.
Repetitive behavior sometimes takes the form of a persistent, intense preoccupation. For example, the
child might be obsessed with learning all about vacuum cleaners, train schedules, or lighthouses. Often
there is great interest in numbers, symbols, or science topics.
Problems that may accompany ASD
Sensory problems
When children's perceptions are accurate, they can learn from what they see, feel, or hear. On the other
hand, if sensory information is faulty, the child's experiences of the world can be confusing. Many ASD
children are highly attuned or even painfully sensitive to certain sounds, textures, tastes, and smells.
Some children find the feel of clothes touching their skin almost unbearable. Some sounds—a vacuum
cleaner, a ringing telephone, a sudden storm, even the sound of waves lapping the shoreline—will cause
these children to cover their ears and scream.
In ASD, the brain seems unable to balance the senses appropriately. Some ASD children are oblivious to
extreme cold or pain. An ASD child may fall and break an arm, yet never cry. Another may bash his head
against a wall and not wince, but a light touch may make the child scream with alarm.
Mental retardation
Many children with ASD have some degree of mental impairment. When tested, some areas of ability may
be normal, while others may be especially weak. For example, a child with ASD may do well on the parts of
the test that measure visual skills but earn low scores on the language subtests.
Seizures
One in four children with ASD develops seizures, often starting either in early childhood or adolescence. 5
Seizures, caused by abnormal electrical activity in the brain, can produce a temporary loss of
consciousness (a “blackout”), a body convulsion, unusual movements, or staring spells. Sometimes a
contributing factor is a lack of sleep or a high fever. An EEG (electroencephalogram—recording of the
electric currents developed in the brain by means of electrodes applied to the scalp) can help confirm the
seizure's presence.
In most cases, seizures can be controlled by a number of medicines called “anticonvulsants.” The dosage
of the medication is adjusted carefully so that the least possible amount of medication will be used to be
effective.
The Diagnosis of Autism Spectrum Disorders
Although there are many concerns about labeling a young child with an ASD, the earlier the diagnosis of
ASD is made, the earlier needed interventions can begin. Evidence over the last 15 years indicates that
intensive early intervention in optimal educational settings for at least 2 years during the preschool years
results in improved outcomes in most young children with ASD.2
In evaluating a child, clinicians rely on behavioral characteristics to make a diagnosis. Some of the
characteristic behaviors of ASD may be apparent in the first few months of a child's life, or they may
appear at any time during the early years. For the diagnosis, problems in at least one of the areas of
communication, socialization, or restricted behavior must be present before the age of 3. The diagnosis
requires a two-stage process. The first stage involves developmental screening during “well child” check-
ups; the second stage entails a comprehensive evaluation by a multidisciplinary team.8
Screening
A “well child” check-up should include a developmental screening test. If your child's pediatrician does not
routinely check your child with such a test, ask that it be done. Your own observations and concerns about
your child's development will be essential in helping to screen your child.8 Reviewing family videotapes,
photos, and baby albums can help parents remember when each behavior was first noticed and when the
child reached certain developmental milestones. Several screening instruments have been developed to
quickly gather information about a child's social and communicative development within medical settings.
Among them are the Checklist of Autism in Toddlers (CHAT),9 the modified Checklist for Autism in
Toddlers (M-CHAT),10 the Screening Tool for Autism in Two-Year-Olds (STAT),11 and the Social
Communication Questionnaire (SCQ)12 (for children 4 years of age and older).
Some screening instruments rely solely on parent responses to a questionnaire, and some rely on a
combination of parent report and observation. Key items on these instruments that appear to differentiate
children with autism from other groups before the age of 2 include pointing and pretend play. Screening
instruments do not provide individual diagnosis but serve to assess the need for referral for possible
diagnosis of ASD. These screening methods may not identify children with mild ASD, such as those with
high-functioning autism or Asperger syndrome.
During the last few years, screening instruments have been devised to screen for Asperger syndrome and
higher functioning autism. The Autism Spectrum Screening Questionnaire (ASSQ),13 the Australian Scale
for Asperger's Syndrome,14 and the most recent, the Childhood Asperger Syndrome Test (CAST),15 are
some of the instruments that are reliable for identification of school-age children with Asperger syndrome
or higher functioning autism. These tools concentrate on social and behavioral impairments in children
without significant language delay.
If, following the screening process or during a routine “well child” check-up, your child's doctor sees any of
the possible indicators of ASD, further evaluation is indicated.
Comprehensive Diagnostic Evaluation
The second stage of diagnosis must be comprehensive in order to accurately rule in or rule out an ASD or
other developmental problem. This evaluation may be done by a multidisciplinary team that includes a
psychologist, a neurologist, a psychiatrist, a speech therapist, or other professionals who diagnose
children with ASD. Because ASDs are complex disorders and may involve other neurological or genetic
problems, a comprehensive evaluation should entail neurologic and genetic assessment, along with in-
depth cognitive and language testing.8 In addition, measures developed specifically for diagnosing autism
are often used. These include the Autism Diagnosis Interview-Revised (ADI-R)16 and the Autism
Diagnostic Observation Schedule (ADOS-G).17 The ADI-R is a structured interview that contains over 100
items and is conducted with a caregiver. It consists of four main factors—the child's communication, social
interaction, repetitive behaviors, and age-of-onset symptoms. The ADOS-G is an observational measure
used to “press” for socio-communicative behaviors that are often delayed, abnormal, or absent in children
with ASD.
Still another instrument often used by professionals is the Childhood Autism Rating Scale (CARS).18 It
aids in evaluating the child's body movements, adaptation to change, listening response, verbal
communication, and relationship to people. It is suitable for use with children over 2 years of age. The
examiner observes the child and also obtains relevant information from the parents. The child's behavior is
rated on a scale based on deviation from the typical behavior of children of the same age.
Two other tests that should be used to assess any child with a developmental delay are a formal
audiologic hearing evaluation and a lead screening. Although some hearing loss can co-occur with ASD,
some children with ASD may be incorrectly thought to have such a loss. In addition, if the child has
suffered from an ear infection, transient hearing loss can occur. Lead screening is essential for children
who remain for a long period of time in the oral-motor stage in which they put any and everything into their
mouths. Children with an autistic disorder usually have elevated blood lead levels.8
Customarily, an expert diagnostic team has the responsibility of thoroughly evaluating the child, assessing
the child's unique strengths and weaknesses, and determining a formal diagnosis. The team will then meet
with the parents to explain the results of the evaluation.
Although parents may have been aware that something was not “quite right” with their child, when the
diagnosis is given, it is a devastating blow. At such a time, it is hard to stay focused on asking questions.
But while members of the evaluation team are together is the best opportunity the parents will have to ask
questions and get recommendations on what further steps they should take for their child. Learning as
much as possible at this meeting is very important, but it is helpful to leave this meeting with the name or
names of professionals who can be contacted if the parents have further questions.
Autism diagnoses are increasing world wide. Autistic children have difficulties with social interaction, problems with verbal and nonverbal communication, and repetitive behaviors or narrow, obsessive interests. New York, Los Angeles, Chicago, Houston, Philadelphia, San Diego, Detroit, Dallas, Phoenix, San Antonio, San Jose, Baltimore, Indianapolis, San Francisco, Jacksonville, Columbus, Milwaukee, Memphis, Washington, Boston, Seattle, St. Louis, Atlanta, Pittsburgh, Minneapolis, Miami, Tampa, London, Paris. Rome, Munich, Moscow, Sydney, Tokyo, Bejing, Shanghai