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Reason of autism


What Causes Autism? | Autism Speaks

The information below is not meant to diagnose or treat. It should not take the place of consultation with a qualified healthcare professional.

A common question after an autism diagnosis is what is the cause of autism. 

We know that there’s no one cause of autism. Research suggests that autism develops from a combination of genetic and nongenetic, or environmental, influences.

These influences appear to increase the risk that a child will develop autism. However, it’s important to keep in mind that increased risk is not the same as cause. For example, some gene changes associated with autism can also be found in people who don’t have the disorder. Similarly, not everyone exposed to an environmental risk factor for autism will develop the disorder. In fact, most will not.

Autism’s genetic risk factors

Research tells us that autism tends to run in families. Changes in certain genes increase the risk that a child will develop autism. If a parent carries one or more of these gene changes, they may get passed to a child (even if the parent does not have autism). Other times, these genetic changes arise spontaneously in an early embryo or the sperm and/or egg that combine to create the embryo. Again, the majority of these gene changes do not cause autism by themselves. They simply increase risk for the disorder

Autism’s environmental risk factors

Research also shows that certain environmental influences may further increase – or reduce – autism risk in people who are genetically predisposed to the disorder. Importantly, the increase or decrease in risk appears to be small for any one of these risk factors:

Increased risk
  • Advanced parent age (either parent)
  • Pregnancy and birth complications (e.g. extreme prematurity [before 26 weeks], low birth weight, multiple pregnancies [twin, triplet, etc.])
  • Pregnancies spaced less than one year apart
Decreased risk
  • Prenatal vitamins containing folic acid, before and at conception and through pregnancy 
No effect on risk

  • Vaccines. Each family has a unique experience with an autism diagnosis, and for some it corresponds with the timing of their child’s vaccinations. At the same time, scientists have conducted extensive research over the last two decades to determine whether there is any link between childhood vaccinations and autism. The results of this research is clear: Vaccines do not cause autism. The American Academy of Pediatrics has compiled a comprehensive list of this research.

Differences in brain biology

How do these genetic and nongenetic influences give rise to autism? Most appear to affect crucial aspects of early brain development. Some appear to affect how brain nerve cells, or neurons, communicate with each other. Others appear to affect how entire regions of the brain communicate with each other. Research continues to explore these differences with an eye to developing treatments and supports that can improve quality of life.

Autism spectrum disorder - Symptoms and causes

Overview

Autism spectrum disorder is a condition related to brain development that impacts how a person perceives and socializes with others, causing problems in social interaction and communication. The disorder also includes limited and repetitive patterns of behavior. The term "spectrum" in autism spectrum disorder refers to the wide range of symptoms and severity.

Autism spectrum disorder includes conditions that were previously considered separate — autism, Asperger's syndrome, childhood disintegrative disorder and an unspecified form of pervasive developmental disorder. Some people still use the term "Asperger's syndrome," which is generally thought to be at the mild end of autism spectrum disorder.

Autism spectrum disorder begins in early childhood and eventually causes problems functioning in society — socially, in school and at work, for example. Often children show symptoms of autism within the first year. A small number of children appear to develop normally in the first year, and then go through a period of regression between 18 and 24 months of age when they develop autism symptoms.

While there is no cure for autism spectrum disorder, intensive, early treatment can make a big difference in the lives of many children.

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Symptoms

Some children show signs of autism spectrum disorder in early infancy, such as reduced eye contact, lack of response to their name or indifference to caregivers. Other children may develop normally for the first few months or years of life, but then suddenly become withdrawn or aggressive or lose language skills they've already acquired. Signs usually are seen by age 2 years.

Each child with autism spectrum disorder is likely to have a unique pattern of behavior and level of severity — from low functioning to high functioning.

Some children with autism spectrum disorder have difficulty learning, and some have signs of lower than normal intelligence. Other children with the disorder have normal to high intelligence — they learn quickly, yet have trouble communicating and applying what they know in everyday life and adjusting to social situations.

Because of the unique mixture of symptoms in each child, severity can sometimes be difficult to determine. It's generally based on the level of impairments and how they impact the ability to function.

Below are some common signs shown by people who have autism spectrum disorder.

Social communication and interaction

A child or adult with autism spectrum disorder may have problems with social interaction and communication skills, including any of these signs:

  • Fails to respond to his or her name or appears not to hear you at times
  • Resists cuddling and holding, and seems to prefer playing alone, retreating into his or her own world
  • Has poor eye contact and lacks facial expression
  • Doesn't speak or has delayed speech, or loses previous ability to say words or sentences
  • Can't start a conversation or keep one going, or only starts one to make requests or label items
  • Speaks with an abnormal tone or rhythm and may use a singsong voice or robot-like speech
  • Repeats words or phrases verbatim, but doesn't understand how to use them
  • Doesn't appear to understand simple questions or directions
  • Doesn't express emotions or feelings and appears unaware of others' feelings
  • Doesn't point at or bring objects to share interest
  • Inappropriately approaches a social interaction by being passive, aggressive or disruptive
  • Has difficulty recognizing nonverbal cues, such as interpreting other people's facial expressions, body postures or tone of voice

Patterns of behavior

A child or adult with autism spectrum disorder may have limited, repetitive patterns of behavior, interests or activities, including any of these signs:

  • Performs repetitive movements, such as rocking, spinning or hand flapping
  • Performs activities that could cause self-harm, such as biting or head-banging
  • Develops specific routines or rituals and becomes disturbed at the slightest change
  • Has problems with coordination or has odd movement patterns, such as clumsiness or walking on toes, and has odd, stiff or exaggerated body language
  • Is fascinated by details of an object, such as the spinning wheels of a toy car, but doesn't understand the overall purpose or function of the object
  • Is unusually sensitive to light, sound or touch, yet may be indifferent to pain or temperature
  • Doesn't engage in imitative or make-believe play
  • Fixates on an object or activity with abnormal intensity or focus
  • Has specific food preferences, such as eating only a few foods, or refusing foods with a certain texture

As they mature, some children with autism spectrum disorder become more engaged with others and show fewer disturbances in behavior. Some, usually those with the least severe problems, eventually may lead normal or near-normal lives. Others, however, continue to have difficulty with language or social skills, and the teen years can bring worse behavioral and emotional problems.

When to see a doctor

Babies develop at their own pace, and many don't follow exact timelines found in some parenting books. But children with autism spectrum disorder usually show some signs of delayed development before age 2 years.

If you're concerned about your child's development or you suspect that your child may have autism spectrum disorder, discuss your concerns with your doctor. The symptoms associated with the disorder can also be linked with other developmental disorders.

Signs of autism spectrum disorder often appear early in development when there are obvious delays in language skills and social interactions. Your doctor may recommend developmental tests to identify if your child has delays in cognitive, language and social skills, if your child:

  • Doesn't respond with a smile or happy expression by 6 months
  • Doesn't mimic sounds or facial expressions by 9 months
  • Doesn't babble or coo by 12 months
  • Doesn't gesture — such as point or wave — by 14 months
  • Doesn't say single words by 16 months
  • Doesn't play "make-believe" or pretend by 18 months
  • Doesn't say two-word phrases by 24 months
  • Loses language skills or social skills at any age

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Causes

Autism spectrum disorder has no single known cause. Given the complexity of the disorder, and the fact that symptoms and severity vary, there are probably many causes. Both genetics and environment may play a role.

  • Genetics. Several different genes appear to be involved in autism spectrum disorder. For some children, autism spectrum disorder can be associated with a genetic disorder, such as Rett syndrome or fragile X syndrome. For other children, genetic changes (mutations) may increase the risk of autism spectrum disorder. Still other genes may affect brain development or the way that brain cells communicate, or they may determine the severity of symptoms. Some genetic mutations seem to be inherited, while others occur spontaneously.
  • Environmental factors. Researchers are currently exploring whether factors such as viral infections, medications or complications during pregnancy, or air pollutants play a role in triggering autism spectrum disorder.

No link between vaccines and autism spectrum disorder

One of the greatest controversies in autism spectrum disorder centers on whether a link exists between the disorder and childhood vaccines. Despite extensive research, no reliable study has shown a link between autism spectrum disorder and any vaccines. In fact, the original study that ignited the debate years ago has been retracted due to poor design and questionable research methods.

Avoiding childhood vaccinations can place your child and others in danger of catching and spreading serious diseases, including whooping cough (pertussis), measles or mumps.

Risk factors

The number of children diagnosed with autism spectrum disorder is rising. It's not clear whether this is due to better detection and reporting or a real increase in the number of cases, or both.

Autism spectrum disorder affects children of all races and nationalities, but certain factors increase a child's risk. These may include:

  • Your child's sex. Boys are about four times more likely to develop autism spectrum disorder than girls are.
  • Family history. Families who have one child with autism spectrum disorder have an increased risk of having another child with the disorder. It's also not uncommon for parents or relatives of a child with autism spectrum disorder to have minor problems with social or communication skills themselves or to engage in certain behaviors typical of the disorder.
  • Other disorders. Children with certain medical conditions have a higher than normal risk of autism spectrum disorder or autism-like symptoms. Examples include fragile X syndrome, an inherited disorder that causes intellectual problems; tuberous sclerosis, a condition in which benign tumors develop in the brain; and Rett syndrome, a genetic condition occurring almost exclusively in girls, which causes slowing of head growth, intellectual disability and loss of purposeful hand use.
  • Extremely preterm babies. Babies born before 26 weeks of gestation may have a greater risk of autism spectrum disorder.
  • Parents' ages. There may be a connection between children born to older parents and autism spectrum disorder, but more research is necessary to establish this link.

Complications

Problems with social interactions, communication and behavior can lead to:

  • Problems in school and with successful learning
  • Employment problems
  • Inability to live independently
  • Social isolation
  • Stress within the family
  • Victimization and being bullied

Prevention

There's no way to prevent autism spectrum disorder, but there are treatment options. Early diagnosis and intervention is most helpful and can improve behavior, skills and language development. However, intervention is helpful at any age. Though children usually don't outgrow autism spectrum disorder symptoms, they may learn to function well.

By Mayo Clinic Staff

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causes, symptoms, diagnosis and treatment

IMPORTANT!

The information in this section should not be used for self-diagnosis or self-treatment. In case of pain or other exacerbation of the disease, only the attending physician should prescribe diagnostic tests. For diagnosis and proper treatment, you should contact your doctor.
For a correct assessment of the results of your analyzes in dynamics, it is preferable to do studies in the same laboratory, since different laboratories may use different research methods and units of measurement to perform the same analyzes.

Definition

Autism, more specifically Autism Spectrum Disorders (ASD), is a group of mental disorders characterized by impairments in social interaction and communication – the process of communicating and passing information to other people. Autism is characterized by limited, stereotyped, repetitive behavior. In different patients, disorders are expressed to varying degrees, while they may or may not be accompanied by impaired speech and intellectual development.

The first signs of the disease are noted already in infancy or early childhood, anomalies in social functioning and behavior persist throughout life.


Causes of autism

The causes of autism spectrum disorders are not fully understood, but it is believed that genetic factors play a leading role. It is known that the risk of having a child with ASD increases with the age of the parents.

Possible relationship between the onset of ASD in a child and the course of pregnancy: prematurity of the fetus, the use of valproic acid preparations by the mother during pregnancy to treat epilepsy, manic-depressive psychosis, migraine, as well as gestational diabetes in the mother (diabetes mellitus that develops during pregnancy ). It is unlikely that any of these factors is of decisive importance in the development of ASD, but may be realized in interaction with a genetic predisposition.

Autism is more commonly diagnosed in boys, with a sex ratio of approximately 3:1.

Since the mid-1990s, there have been concerns about the possible association of vaccination with the onset of ASD. Current epidemiological data indicate no such association. Moreover, there is no evidence of an association between the use of vaccines and the risk of developing ASD, even when vaccinating children at risk - brothers and sisters of children with ASD. It has been proven that the preservative thiomersal and aluminum adjuvant contained in inactivated vaccines do not increase the likelihood of ASD in vaccinated children. According to many international studies, changes in the vaccination schedule, the withdrawal of any vaccines and their components did not affect the incidence of ASD.

Disease classification

Depending on the number of symptoms and their severity, there are three main types of ASD: childhood autism, atypical autism, and Asperger's syndrome.

Asperger's syndrome is the mildest form of ASD - intelligence does not suffer, changes can be regarded as personality traits and do not interfere with professional development and social adaptation of a person.

There is a division of the RAS depending on the presence or absence of intellectual disabilities and the ability of a person to use spoken or written language as a means to express needs or desires.

Symptoms of autism

The main manifestations of ASD are disorders in social interaction, communication (anomalies in communication) and limited, stereotyped, repetitive behavior. In addition, patients often have other non-specific problems: various phobias (fears), sleep and nutrition disorders, aggression and auto-aggression (aggression directed at oneself). Contrary to popular belief, most autism spectrum disorders are not associated with a high level of intelligence, although some patients may have extraordinary abilities in some area of ​​knowledge.

Let us dwell in more detail on the description of the main manifestations of the disease.

Disorders of social interaction and social communication . Parents pay attention to the fact that the child rarely uses eye contact, gestures, facial expressions and posture to regulate social interaction, he has reduced interest in interacting with peers and adults. The child may not speak or start speaking with a strong delay, and if he does, he does not start a conversation, does not ask questions, communicates exclusively on topics of interest to him; can repeat the same words and phrases over and over. The baby has no desire to walk in his arms, he does not always distinguish parents from other people. Such children do not look at the interlocutor, may not respond to the speech addressed to them, to requests, do not respond to the name, they do not enter into or reluctantly enter into a dialogue, do not smile in response.

Often, a child with autism can observe unusual behavior, for example, violation of bodily boundaries, lack of embarrassment or excessive anxiety when interacting with new people, monotonous scenarios in communication.

After the age of 7 years, some children with ASD remain speechless or have a minimal set of words. Other children, starting to communicate, cannot build long-term friendships and take into account social rules. The problem of many older children and adults with autism is the inability to understand and feel the state of other people, their mood.

People with ASD are characterized by naivete, innocence, they do not understand irony and humor well, they experience difficulties in maintaining a dialogue and understanding the rules of behavior.

Many patients with ASD retain excessive or, conversely, absent gesticulation, unstable or excessive eye contact.

Stereotyped, repetitive behavior, limited interests and hobbies . With the exception of Asperger's syndrome, most patients present with varying degrees of intellectual decline. Children with ASD are characterized by peculiar play activities, for example, a child may use toys in an unusual way: scatter, lick or perform other repetitive manipulations. Already in early childhood, selective interests often appear - for example, it can be the study of moving objects, a passion for narrow topics (interest in the alphabet, numbers, names and individual characteristics of objects). Such children experience pronounced difficulties when it is necessary to switch attention.

With age, the set of symptoms may change in content and severity. Many older children and adults are characterized by inflexibility of thinking, manifested by a lack of response to changing environmental conditions, the difficulty of assimilating and using new information, practical skills, and an excessive tendency to detail.

Autism Diagnostics

When collecting complaints and examining, the doctor draws attention to the characteristics of the patient's behavior, assesses the current psychiatric status and level of development.

To clarify the diagnosis and improve the accuracy of clinical diagnostics, additional standardized methods related to the "gold standard" are used: ADOS-II and ADI-R.

ADOS-II is a test performed by a child or adult psychiatrist or clinical psychologist. It consists in observing the patient performing certain tasks in a playful way. Depending on age, ability to speak and play, the doctor chooses one or another module - a type of testing. The modules differ in the complexity of the proposed games, activities and the presence of speech tasks. The 1st module is used for children speaking in separate words. 2nd - for children using sentences of several words. 3rd - for freely communicating children. 4th - for freely communicating teenagers and adults. With the help of a certain set of toys and items, the specialist creates various game situations. He observes the performance of the work, evaluating facial expressions, words, ways of solving the proposed tasks. The tasks last about an hour, after which the specialist processes the test results and draws up a conclusion. Usually, the test is recorded on video, which helps to make a more accurate diagnosis and provides an opportunity for other specialists to assess the child's condition.

ADOS-II is not the only criterion for making a diagnosis. As an additional test to collect more data, the ADI-R screening can be used.

ADI-R - an interview with about 100 questions conducted by a psychologist or psychiatrist; but not with the patient, but with his parents or other close people. The questions are aimed at assessing:

  • the quality of social contact;
  • quality of communication and speech features,
  • behavior patterns (repetitive, limited or stereotyped actions).

Genetic testing may be recommended in children and adolescents with an established diagnosis to clarify the immediate cause of ASD. It is compiled according to an individual plan with the involvement of geneticists or other specialists.

Instrumental methods of examination are of secondary importance, not leading in the diagnosis of ASD. Electroencephalography (EEG), computed tomography (CT) of the brain, and magnetic resonance imaging (MRI) of the brain are not recommended for all children and adolescents with or suspected ASD. On the one hand, this is due to the fact that the examination may be difficult due to ASD-specific violations of the patient's communication and behavioral skills. On the other hand, these studies cannot confirm or refute the diagnosis of autism spectrum disorder, but may be indicated for diagnosis and treatment in case of suspected presence of other disorders, for example, epilepsy, brain tumor.

Which doctors to contact

Autism can be suspected pediatrician. Confirms the diagnosis, prescribes therapy and observes children, and then an adult psychiatrist, neuropathologist, psychologist.

Autism treatment

There is currently no direct treatment for ASD. Prescribed medications, for example, from the group of antidepressants, can help in solving various non-specific problems - sleep and nutrition disorders, increased irritability, attacks of aggression directed at oneself or others. The main treatments for ASD are predominantly non-pharmacological in nature. They include educational and psychological assistance aimed at the socialization of a person with ASD - the earlier assistance is started, the better the prognosis for the development of the child.

There are many methods of treatment and care for patients with ASD that have no proven effectiveness: gluten-free and casein-free diets, brain micropolarization, the Tomatis method, bioacoustic correction, art therapy, as well as hippotherapy, dolphin therapy and many others. If parents insist on using these methods, it is important to understand that they should not be used as a substitute for the main treatment program.

Nootropic and peptide drugs are often used in the treatment of patients with ASD. Currently, there is no convincing evidence of their ability to influence the development of cognitive and speech skills. However, they can increase motor activity, cause disinhibition and sleep disorders.

Complications of the disease

With autism, various damages are possible that the patient inflicts on himself and others.

Due to impaired cognitive functions, speech, difficulties in interacting with others, patients with ASD, with the exception of patients with Asperger's syndrome, in most cases cannot live independently, study and work.

Diagnosis and treatment of other diseases are difficult due to the high pain threshold and behavioral characteristics of those suffering from ASD.

Prevention of autism

There are currently no specific measures to prevent ASD. However, early diagnosis is a necessary condition for organizing early comprehensive care for a child, which can improve the prognosis.

Sources:

  1. Clinical guidelines. Autism Spectrum Disorders. Clinical recommendation developer Association of Psychiatrists and Psychologists for evidence-based practice Approved by the Scientific and Practical Council of the Ministry of Health of the Russian Federation, 2020. - p. 52.
  2. Bozhkova E.D., Balandina O.V., Konovalov A.A. Autism Spectrum Disorders: Current State of the Problem (Review). Modern technologies in medicine. T. 12, No. 2, 2020. S. 111-120.

IMPORTANT!

The information in this section should not be used for self-diagnosis or self-treatment. In case of pain or other exacerbation of the disease, only the attending physician should prescribe diagnostic tests. For diagnosis and proper treatment, you should contact your doctor.
For a correct assessment of the results of your analyzes over time, it is preferable to do studies in the same laboratory, since different laboratories may use different research methods and units of measurement to perform the same analyzes.


Autism in children (treatment and prevention)

Children's Medical Center of Neurology and Pediatrics near the metro station Kolomenskaya offers a service - treatment and prevention of autism in children.

Our center employs only highly qualified specialists who will provide all the necessary assistance in the treatment of autism.

Causes of autism in children

Autism in children is a type of nervous system disorder caused by various factors. Most scientists agree that genes are the biggest risk factor for disease: mismutation, inheritance, and so on. Another theory says that autism manifests itself as a result of external factors: poor ecology, difficult pregnancy and birth complications, the use of certain medications during pregnancy. Older parents are also at risk. Some people mistakenly believe that vaccination can lead to the manifestation of the disease, but this is not so. Global studies have shown that there is no link between vaccination and the manifestation of autism. The disease is recorded in all social strata and ethnic groups, but affects the male sex to a greater extent.

Signs of autism in children under one year old

The manifestation of autism is characterized by difficulties in social interaction, communication problems and a tendency to repetitive behavior. Symptoms and their severity vary in these three planes. Often, autism is accompanied by comorbidities such as seizure disorder, sleep disturbance, gastrointestinal problems, and sensory processing problems. The ability to learn and think can range from gifted children to serious mental health problems, all the way to disability. Diagnosis of the disease can be quite difficult, since there are no universal tests, blood tests, etc. that clearly indicate the problem. The doctor focuses solely on the behavior and general development of the baby. As a rule, an accurate diagnosis is made by a group of doctors - a psychiatrist, a neuropathologist and a psychologist.

However, in most cases, parents can focus on indirect signs of the manifestation of the disease. It should be remembered that the sooner you sound the alarm, the more chances to improve the situation. Any infant is, as a rule, social by nature, and this is not surprising, since social skills are built into us by evolutionary processes. The kid reacts to his mother, shows joy and grief, not yet able to speak, tries to convey his feelings and emotions to those around him. Children with autism have difficulty engaging in everyday human interactions. Between the ages of 8 and 10 months, these babies begin to show some symptoms, such as: ignoring the mother's voice, decreased interest in people, delayed reaction. During childhood, many children with autism have difficulty with social play, do not imitate the actions of others, and prefer to play alone. They do not seek the attention of their parents, do not respond to their comments.

Treatment of autism in children

Unfortunately, there is no universal cure for this disease. However, this does not mean that the parents of a child with autism should give up and sprinkle ashes on their heads. There are many methods that allow you to socialize such a child. Yes, albeit not completely, but it is much better than leaving everything as it is. Let the child be in himself, but why not help him cope with daily tasks so that he can serve himself and become partially independent?! It is this “maximum” task that the treating specialist faces. Treatment for autism is a highly individual process. Therapy that went well with one child can only harm another.

Typically, treatment includes behavioral modification and drug therapy, which may be required if the comorbidities we mentioned earlier are found. Working with family members of the baby. Gradual involvement in the process of communication and learning can allow the development of a number of socially oriented skills.

Researchers have developed a range of effective early intervention models with significant results. They include: