If your child is experiencing social developmental delays, you should learn about pervasive developmental disorders (PDD) and PDD symptoms. A child who experiences developmental delays may still catch up and experience a healthy childhood. Yet sometimes a development delay is the sign of a serious condition.
Pervasive Development Disorders
PDD and Autism Spectrum Disorder
The Diagnostic Statistical Manual, Fourth Edition (DSM-IV) is the standard classification system of American mental health professionals. It uses the term pervasive developmental disorders to categorize the following five neurological disorders:
- Autistic disorder or autism
- Asperger's syndrome
- Pervasive development disorder-not otherwise specified (PDD NOS)
- Rett syndrome
- Childhood disintegrative disorder
Each of the five disorders is considered a PDD. Diagnosis of a PDD is based upon a specific diagnosis criteria outlined in the DSM-IV.
There is some controversy over categorizing autism disorders with DSM-IV terminology, whether it should be PDD or as the autism spectrum of disorders. Many experts prefer to classify different types of autism as the autism spectrum of disorders because the spectrum provides a more detailed description of various autistic disorder symptoms and makes diagnosis easier. PDD disorders are generally diagnosed during childhood. However, sometimes a person with lifelong mild PDD symptoms can go without a diagnosis until adulthood.
Common PDD Symptoms
Every case of PDD is unique and not every person will experience the same number of symptoms or level of impairment. Each of the five conditions shares PDD symptoms involving severe impairment in speech, communication and social interaction. A person with a PDD usually experiences early childhood developmental delays in some of these areas.
Speech, Language and Communication Difficulties
A person with a PDD has limited or no language skills. In fact, a PDD patient may not talk at all. She often has trouble understanding what others say. For example, a PDD patient might not respond to her name or follow basic instructions. She may use speech inappropriately such as saying, "you," when she means "I." A person with PDD symptoms may exhibit echolalia, the habit of irrationally repeating phrases that they hear. She might repeat the phrase immediately after hearing it or hours later out of context. The PDD can prevent a person from comprehending a common communication gesture such as a wave. She will not respond to common communication gestures. Other speech and communication symptoms may include:
- Speaking in a monotone voice
- Inability to control loud or soft speech
- Talking about favorite topics out loud but not engaging in a two-person conversation
- Has a large vocabulary and speech capacity but unable to listen to others
Lack of Social Skills
The person with a PDD will isolate herself from others. She shows no interest in interacting with others. If she is interested in other people, she seems unaware how to talk or interact with them. She may not smile at others, including family. Social skill problems can also involve:
- Refuses to make eye contact with others
- Difficulty developing a relationship with family or friends
- Does not like physical contact with others such as a handshake or hug
- There is no perception of body space. She might stand too close to someone when she is talking.
Repetitive and Obsessive Behaviors
A PDD patient often prefers to follow strict routines. When the routine is interrupted, she gets very angry. She fixates on an object or activity for hours. She might irrationally repeat actions such as always washing her hands five times. Some other common repetitive and obsessive behaviors can include:
- Repetitive voluntary body movement such as rocking back and forth, arm flapping or other unusual body movements
- Intense focus on the small details of an object or subject
- May injure self with certain repetitive behaviors such as head-banging
- Strong preference for certain food choices and intolerant of trying new foods
Inability to Control Emotions
A person with a PDD may not understand how to process and react to emotions appropriately. She often does not understand her own emotions and may get irrationally upset when encountering something that triggers a negative reaction.
- Unable to understand what others are feeling
- Inability to communicate her emotions appropriately
- Extreme mood swings
- Random inappropriate emotional responses
Symptom Differences in the Five Disorders
The five PDD disorders have similar symptoms but with a number of key differences specific to each condition. Here are some of the differences in PDD symptoms among the five disorders:
- Usually occurs before three years old
- Has limited language skills or may be nonverbal
- Prefers solitude
- Rett's Syndrome Symptoms
- Only affects girls
- Develops normally until about 6 months of age
- Head size does not grow at normal rate
- Asperger's Syndrome Symptoms
- Has large vocabulary and interest in people but has trouble interacting socially and communicating with others
- The ability to focus on small details that would normally not interest the average person
- Fixates on an activity for hours
- Childhood Disintegrative Disorder Symptoms
- Develops normally until 3 or 4 years old
- Gradually regresses and loses speech, language, communication and social interaction abilities
- Loses previously learned potty-training
- Exhibits many of the symptoms of the other four disorders but not at a high enough level to be diagnosed with any of them by DSM-IV standards
- Has better communication and cognitive skills than people with other PDD conditions
Conditions with Similar SymptomsA number of other neurological conditions may mimic PDD symptoms. These conditions include:
- Mental retardation
- Childhood schizophrenia
- Obsessive-compulsive disorders
- Attention deficit hyperactivity disorder
How to Seek Help
If you believe that your child or loved one exhibits PDD symptoms, contact a doctor immediately for a diagnosis. You can also contact your local early childhood intervention program for assistance in seeking a diagnosis for a child under three.
Don't be discouraged by the diagnosis. Many people with PDD respond well to therapy and medication. Develop a support network for your loved one and yourself by contacting local support groups. For more information on PDD, visit the Autism Help site and the National Autism Association.