Autistic spectrum disorders

Autistic spectrum disorders are complex developmental disorders, which include autism, Asperger's syndrome, childhood disintegrative disorder (CDD), Rett syndrome and pervasive developmental disorder (PDD) not otherwise specified. All of these disorders involve problems with:

• Social interactions
• Verbal and nonverbal communication
• Repetitive behaviors or interests

These disorders are known as spectrum disorders because the signs and symptoms of each can appear in different combinations and in varying degrees of severity. Two children with the same diagnosis may share certain patterns of behavior but can exhibit a wide range of skills and abilities.

A child with an autistic spectrum disorder may develop normally for the first few months or years of life, then become less responsive to other people. These disorders can often be reliably detected by the age of 3 years, and in some cases as early as 18 months. Still, it's estimated that only 50 percent of children with autistic spectrum disorders are diagnosed before kindergarten. Delayed speech is one common indicator of such a disorder. However, it's important to note that not all children with delayed speech have an autistic spectrum disorder.

Doctors and researchers don't understand what causes autistic spectrum disorders. But they seem to have a strong genetic component. They also may be associated with abnormalities in certain parts of the brain. Researchers are aggressively exploring these theories and others.

Guidelines for diagnosis and treatment of autistic spectrum disorders are still evolving. But early interventions and special education are already helping many children. If you have concerns about your child's speech and language or social development, discuss them with your doctor.