Autism
Overview
![Picture](/uploads/1/6/9/7/16973174/1362344298.jpg)
Autism spectrum disorder (ASD) and autism are both general terms for a group of complex disorders of brain development. These disorders are characterized, in varying degrees, by difficulties in social interaction, verbal and nonverbal communication and repetitive behaviors. They include autistic disorder, Rett syndrome, childhood disintegrative disorder, pervasive developmental disorder-not otherwise specified (PDD-NOS) and Asperger syndrome. ASD can be associated with intellectual disability, difficulties in motor coordination and attention and physical health issues such as sleep and gastrointestinal disturbances. Some persons with ASD excel in visual skills, music, math and art.
Causes and Symptoms
![Picture](/uploads/1/6/9/7/16973174/4436136.jpg?1362348627)
Causes:
It has long been presumed that there is a common cause at the genetic, cognitive, and neural levels for autism's characteristic triad of symptoms. However, there is increasing suspicion that autism is instead a complex disorder whose core aspects have distinct causes that often co-occur. Autism has a strong genetic basis, although the genetics of autism are complex and it is unclear whether ASD is explained more by rare mutations with major effects, or by rare multi-gene interactions of common genetic variants. Complexity arises due to interactions among multiple genes, the environment, and epigenetic factors which do not change DNA but are heritable and influence gene expression. Typically, autism cannot be traced to a single-gene mutation or to a single chromosome abnormality, and none of the genetic syndromes associated with ASDs have been shown to selectively cause ASD. The large number of autistic individuals with unaffected family members may result from spontaneous deletions or duplications in genetic material during meiosis. Hence, a substantial fraction of autism cases may be traceable to genetic causes that are highly heritable but not inherited. Several lines of evidence point to synaptic dysfunction as a cause of autism. Some rare mutations may lead to autism by disrupting some synaptic pathways, such as those involved with cell adhesion. Gene replacement studies in mice suggest that autistic symptoms are closely related to later developmental steps that depend on activity in synapses and on activity-dependent changes. All known teratogens (agents that cause birth defects) related to the risk of autism appear to act during the first eight weeks from conception, and though this does not exclude the possibility that autism can be initiated or affected later, it is strong evidence that autism arises very early in development. Environmental factors that have been claimed to contribute to or exacerbate autism, or may be important in future research, include certain foods, infectious diseases, heavy metals, solvents, diesel exhaust, PCBs, phthalates, and phenols used in plastic products, pesticides, brominated flame retardants, alcohol, smoking, illicit drugs, vaccines, and prenatal stress.
Symptoms:
Parents may first become aware of autistic symptoms in their child around the time of a routine vaccination. Children with autism generally have problems in three crucial areas of development - social interaction, language, and behavior. Because autistic symptoms and severity vary greatly, two children with the same diagnosis may act quite differently and have very different skills. In most cases, children have marked impairments or a complete inability to communicate or interact with other people. Some children show signs of autism in early infancy. Others many develop normally for the first few months or years of life, but then suddenly become withdrawn or aggressive or lose language skills they have already acquired. Though each child with autism is likely to have a unique pattern of behavior, some of the common autism symptoms are:
Social skills
Language
Behavior
It has long been presumed that there is a common cause at the genetic, cognitive, and neural levels for autism's characteristic triad of symptoms. However, there is increasing suspicion that autism is instead a complex disorder whose core aspects have distinct causes that often co-occur. Autism has a strong genetic basis, although the genetics of autism are complex and it is unclear whether ASD is explained more by rare mutations with major effects, or by rare multi-gene interactions of common genetic variants. Complexity arises due to interactions among multiple genes, the environment, and epigenetic factors which do not change DNA but are heritable and influence gene expression. Typically, autism cannot be traced to a single-gene mutation or to a single chromosome abnormality, and none of the genetic syndromes associated with ASDs have been shown to selectively cause ASD. The large number of autistic individuals with unaffected family members may result from spontaneous deletions or duplications in genetic material during meiosis. Hence, a substantial fraction of autism cases may be traceable to genetic causes that are highly heritable but not inherited. Several lines of evidence point to synaptic dysfunction as a cause of autism. Some rare mutations may lead to autism by disrupting some synaptic pathways, such as those involved with cell adhesion. Gene replacement studies in mice suggest that autistic symptoms are closely related to later developmental steps that depend on activity in synapses and on activity-dependent changes. All known teratogens (agents that cause birth defects) related to the risk of autism appear to act during the first eight weeks from conception, and though this does not exclude the possibility that autism can be initiated or affected later, it is strong evidence that autism arises very early in development. Environmental factors that have been claimed to contribute to or exacerbate autism, or may be important in future research, include certain foods, infectious diseases, heavy metals, solvents, diesel exhaust, PCBs, phthalates, and phenols used in plastic products, pesticides, brominated flame retardants, alcohol, smoking, illicit drugs, vaccines, and prenatal stress.
Symptoms:
Parents may first become aware of autistic symptoms in their child around the time of a routine vaccination. Children with autism generally have problems in three crucial areas of development - social interaction, language, and behavior. Because autistic symptoms and severity vary greatly, two children with the same diagnosis may act quite differently and have very different skills. In most cases, children have marked impairments or a complete inability to communicate or interact with other people. Some children show signs of autism in early infancy. Others many develop normally for the first few months or years of life, but then suddenly become withdrawn or aggressive or lose language skills they have already acquired. Though each child with autism is likely to have a unique pattern of behavior, some of the common autism symptoms are:
Social skills
- Fails to respond to his or her name
- Has poor eye contact
- Appears not to hear you at times
- Resists cuddling and holding
- Appears unaware of others' feelings
- Seems to prefer playing alone — retreats into his or her own world
- Doesn't ask for help or request things
Language
- Doesn't speak or has delayed speech
- Loses previously acquired ability to say words or sentences
- Doesn't make eye contact when making requests
- Speaks with an abnormal tone or rhythm — may use a singsong voice or robot-like speech
- Can't start a conversation or keep one going
- May repeat words or phrases verbatim, but doesn't understand how to use them
- Doesn't appear to understand simple questions or directions
Behavior
- Performs repetitive movements, such as rocking, spinning or hand flapping
- Develops specific routines or rituals and becomes disturbed at the slightest change
- Moves constantly
- May be fascinated by details of an object, such as the spinning wheels of a toy car
- May be unusually sensitive to light, sound and touch, and yet oblivious to pain
- Does not engage in imitative or make-believe play
- May have odd food preferences, such as eating only a few foods, or craving items that are not food
- May perform activities that could cause self-harm, such as head banging
Diagnosis and Cures
![Picture](/uploads/1/6/9/7/16973174/6441591.jpg?332)
Diagnosis:
Diagnosis is based on behavior. Autism is defined as exhibiting at least six symptoms total, including at least two symptoms of qualitative impairment in social interaction, at least one symptom of qualitative impairment in communication, and at least one symptom of restricted and repetitive behavior. Onset must be prior to age three years, with delays or abnormal functioning in either social interaction, language as used in social communication, or symbolic or imaginative play. A pediatrician commonly performs a preliminary investigation by taking developmental history and physically examining the child. If warranted, diagnosis and evaluations are conducted with help from ASD specialists, observing and assessing cognitive, communication, family, and other factors using standardized tools, and taking into account any associated medical conditions. A differential diagnosis for ASD at this stage might also consider mental retardation, hearing impairment, and a specific language impairment such as Landau–Kleffner syndrome. Clinical genetics evaluations are often done once ASD is diagnosed, particularly when other symptoms already suggest a genetic cause. ASD can sometimes be diagnosed by age 14 months, although diagnosis becomes increasingly stable over the first three years of life. Under-diagnosis and over-diagnosis are problems in marginal cases, and much of the recent increase in the number of reported ASD cases is likely due to changes in diagnostic practices.
Cures:
No cure exists for autism, and there is no standardized treatment. The range of home-based and school-based treatments and interventions for autism can be overwhelming. The goal of treatment is to maximize your child's ability to function by reducing autism symptoms and supporting development and learning. Your doctor can help identify resources in your area. Treatment options may include:
Diagnosis is based on behavior. Autism is defined as exhibiting at least six symptoms total, including at least two symptoms of qualitative impairment in social interaction, at least one symptom of qualitative impairment in communication, and at least one symptom of restricted and repetitive behavior. Onset must be prior to age three years, with delays or abnormal functioning in either social interaction, language as used in social communication, or symbolic or imaginative play. A pediatrician commonly performs a preliminary investigation by taking developmental history and physically examining the child. If warranted, diagnosis and evaluations are conducted with help from ASD specialists, observing and assessing cognitive, communication, family, and other factors using standardized tools, and taking into account any associated medical conditions. A differential diagnosis for ASD at this stage might also consider mental retardation, hearing impairment, and a specific language impairment such as Landau–Kleffner syndrome. Clinical genetics evaluations are often done once ASD is diagnosed, particularly when other symptoms already suggest a genetic cause. ASD can sometimes be diagnosed by age 14 months, although diagnosis becomes increasingly stable over the first three years of life. Under-diagnosis and over-diagnosis are problems in marginal cases, and much of the recent increase in the number of reported ASD cases is likely due to changes in diagnostic practices.
Cures:
No cure exists for autism, and there is no standardized treatment. The range of home-based and school-based treatments and interventions for autism can be overwhelming. The goal of treatment is to maximize your child's ability to function by reducing autism symptoms and supporting development and learning. Your doctor can help identify resources in your area. Treatment options may include:
- Behavior and communication therapies – Many programs address the range of social, language and behavioral difficulties associated with autism. Some programs focus on reducing problem behaviors and teaching new skills. Others focus on teaching children how to act in social situations or how to communicate better with other people.
- Educational therapies – Children with autism often respond well to highly structured education programs. Successful programs often include a team of specialists and a variety of activities to improve social skills, communication and behavior.
- Family therapies – Parents and family members can learn how to play and interact with their children in ways that promote social interaction skills, manage problem behaviors, and teach daily living skills and communication.
- Medications – No medication can improve the core signs of autism, but certain medications can help control symptoms. For example, anti-depressants may be prescribed for anxiety, and anti-psychotic drugs are sometimes used to treat severe behavioral problems. Other medications may be prescribed if your child is hyperactive.