Autism is a pervasive developmentaldisorder (PDD), a group of illnesses that involve delays in the development of many basic skills, most notably the ability to socialize or form relationships with others as well as the ability to communicate and to use imagination (including fantasy play). Children with autism and related disorders often are confused in their thinking and generally have problems understanding the world around them.

In addition to problems with social interaction, imagination, and communication, children with autism also have a limited range of interests. Many children with autism (nearly 75%) also have mental retardation. In many cases, children with autism are unable to emotionally bond with their parents or other family members.

Autism affects an estimated 10 to 20 of every 10,000 people. It is about 4 times more common in boys as in girls.

Symptoms typically appear before a child is 3 years old and last throughout life. Children with autism can display a wide range of symptoms, which can vary in severity from mild to disabling. General symptoms that may be present to some degree in a child with autism include:

   Difficulty with verbal communication, including problems using and understanding language.
   Inability to participate in a conversation, even when the child has the ability to speak.
   Difficulty with non-verbal communication, such as gestures and facial expressions. Difficulty with social interaction, including relating to people and to his or her surroundings.
   Inability to make friends and preferring to play alone.
   Unusual ways of playing with toys and other objects, such as only lining them up a certain way.
   Lack of imagination.
   Difficulty adjusting to changes in routine or familiar surroundings, or an unreasonable insistence on following routines in detail.
   Repetitive body movements, or patterns of behavior, such as hand flapping, spinning and head banging.
   Preoccupation with unusual objects or parts of objects.
People with a form of autism, called savantism, have exceptional skills in specific areas such as music, art, and numbers. People with savantism are able to perform these skills without lessons or practice.

Individuals with autism usually exhibit at least half of the traits listed below. These symptoms can range from mild to severe and vary in intensity from symptom to symptom. In addition, the behavior usually occurs across many different situations and is consistently inappropriate for their age.

Babies develop at their own pace, some more quickly than others. However, you should consider an evaluation for autism if any of the following apply:

   Your child does not babble or coo by 12 months of age.
   Your child does not gesture, such as point or wave, by 12 months of age.
   Your child does not say single words by 16 months.
   Your child does not say two-word phrases on his or her own (rather than just repeating what someone else says) by 24 months.
   Your child has lost any language or social skills (at any age).

The exact cause of autism is not known, but research has pointed to several possible factors, including genetics (heredity), certain types of infections, and problems occurring at birth.

Recent studies strongly suggest that some people have a genetic predisposition to autism, meaning that a susceptibility to develop the condition may be passed on from parents to children. Researchers are looking for clues about which genes contribute to this increased vulnerability. In some children, environmental factors may also play a role. Studies of people with autism have found abnormalities in several regions of the brain, which suggest that autism results from a disruption of early brain development while still in utero.

Other theories suggest:
The body's immune system may inappropriately produce antibodies that attack the brains of children causing autism.Abnormalities in brain structures cause autistic behavior. Children with autism have abnormal timing of the growth of their brains. Early in childhood, the brains of autistic children grow faster and larger than those of normal children. Later, when normal children's brains get bigger and better organized, autistic kids' brains grow more slowly.

To date there is no convincing evidence that any vaccine can cause autism or any kind of behavioral disorder. A suspected link between the measles, mumps, rubella (MMR) vaccine and autism has been suggested by some parents of children with autism. Typically, symptoms of autism are first noted by parents as their child begins to have difficulty with delays in speaking after age one. The MMR vaccine is first given to children at 12 to 15 months of age. Therefore, autism cases with an apparent onset within a few weeks after the MMR vaccination may simply be an unrelated chance occurrence.

If symptoms are present, the doctor will begin an evaluation by performing a complete medical history and physical examination. Although there are no laboratory tests for autism, the doctor may use various tests -- such as X-rays and blood tests -- to determine if there is a physical disorder causing the symptoms.

If no physical disorder is found, the child may be referred to a specialist in childhood development disorders, such as a child and adolescent psychiatrist or psychologist, pediatric neurologist, developmental pediatrician, or another health professional who is specially trained to diagnose and treat autism. The doctor bases his or her diagnosis on the child's level of development, and the doctor's observation of the child's speech and behavior, including his or her play and ability to socialize with others. The doctor often seeks input from the child's parents, teachers, and other adults who are familiar with the child's symptoms.

Subtypes of autism include:
   Autistic disorder
   Asperger's syndrome
   Rett syndrome
   Childhood disintegrative disorder
   Pervasive developmental disorder

There currently is no cure for autism, but treatment may allow for relatively normal development in the child and reduce undesirable behaviors. Children with autism generally benefit most from a highly structured environment and the use of routines. Treatment for autism may include a combination of the following:

   Special education: Education is structured to meet the child's unique educational needs.
   Behavior modification: This includes strategies for supporting positive behavior and decreasing problem behavior by the child.
   Speech, physical, or occupational therapy: These therapies are designed to increase the child's functional abilities.
   Medication: There are no medications currently approved to treat autism, but medications may be used to treat specific symptoms, such as anxiety (nervousness), hyperactivity, and behavior that may result in injury. A recent study found that a drug often used to treat schizophrenia in adults, called Risperdal, might benefit children with autism.

In 2001, a major study showed that a promising new therapy, called secretin (a digestive hormone), does not treat autism.

The outlook varies depending on the severity of symptoms, the age at which treatment is started, and the availability of supportive resources for the child. Symptoms in many children improve with intervention or as the children age. Some people with autism are able to lead normal or near-normal lives. However, many children with autism do not develop enough functional and communication skills to live independently as adults. The outlook is better for children with higher levels of intelligence who are able to communicate with language.

The National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health, is studying brain abnormalities that may cause autism and is looking for genes that may increase the risk of autism. Researchers also are investigating possible biologic markers present at birth that can identify infants at risk for developing autism. Other studies are examining how different brain regions develop and function in relation to each other, and how alterations in these relationships may result in the signs and symptoms of autism. Researchers hope these studies will provide new clues about how autism develops and how brain abnormalities affect behavior.

Autism cannot be prevented or cured. However, early diagnosis and intervention is critical and may help to maximize a child with autism's ability to speak, learn and function. It is very important that all children see a pediatrician regularly so that any signs of autism can be detected early. The earlier treatment is started, the more effective it can be.

Reviewed by the doctors at The Cleveland Clinic Department of Psychiatry and Psychology.
Source: WebMD