Pervasive Developmental Disorder
Alternate Names : PDD
Pervasive developmental disorder, or PDD, is a set of complex
disorders that affect the brain. PDDs are characterized by an intense
difficulty in social interaction and communication with others.
What is going on in the body?
PDD is a neurological disorder that affects the brain. It appears to affect the
way a person reacts and interacts with others. PDD affects boys four times more often than girls. It is equally prevalent in
people from all parts of society.
There are several different disorders that fall under the category of pervasive
Autistic disorder, or autism,
the most severe of the PDDs. A person with autism has extreme difficulty in
social interactions and communication. This is obvious before the age of 3
Asperger's disorder includes symptoms of difficulty in social interactions
and little interest in activities. There usually is no difficulty with language
skills. The person may be average or above average for age in intellectual
Rett's disorder is only seen in girls. It is characterized by normal
behavior at first and then sudden loss of skills and loss of control of the
hands. This is followed by repetitive hand gestures, such as flapping. Symptoms
usually begin between the ages of 1 and 4 years.
disorder, or CDD, is a disorder in which normal development is seen
until the age of 2 years and then a loss of social skills and a tendency toward
autistic behavior occurs.
Pervasive developmental disorder-nonspecific may be considered when
symptoms of the other disorders are not present but there is a considerable
difficulty with specific behaviors.
Symptoms can vary in intensity in any of these disorders. Some people may have
severe symptoms that affect their lives dramatically. Others have symptoms that
they are able to adjust for easily.
What are the causes and risks of the disease?
The causes of PDD are not well known. Some cases may be genetic, although this
has not been proven. What is known is that PDD is not caused by bad parenting,
mental illness, or "that a kid just doesn't want to behave." Psychological
factors have not been found to contribute to PDD.
Some cases of PDD have been associated with trauma, disease, or structural
abnormalities before or during birth, including:
the mother having rubella, or
German measles, while she was
untreated phenylketonuria, a
problem in the body's ability to handle certain chemicals named phenylketones
lack of oxygen during birth
encephalitis or other serious
infections affecting the brain as an infant
spasms from a variety of illnesses during infancy