What are Pervasive Developmental Disorders?
According to the National Institute of Neuroligical Disorders and Stroke, the diagnostic category of pervasive developmental disorders (PDD) refers to a group of disorders characterized by delays in the development of socialization and communication skills. Parents may note symptoms as early as infancy, although the typical age of onset is before 3 years of age. Symptoms may include problems with using and understanding language; difficulty relating to people, objects, and events; unusual play with toys and other objects; difficulty with changes in routine or familiar surroundings, and repetitive body movements or behavior patterns. Autism (a developmental brain disorder characterized by impaired social interaction and communication skills, and a limited range of activities and interests) is the most characteristic and best studied PDD. Other types of PDD include Asperger's Syndrome, Childhood Disintegrative Disorder, and Rett's Syndrome. Children with PDD vary widely in abilities, intelligence, and behaviors. Some children do not speak at all, others speak in limited phrases or conversations, and some have relatively normal language development. Repetitive play skills and limited social skills are generally evident. Unusual responses to sensory information, such as loud noises and lights, are also common.

Click here to review a study on "The quality of life of children with pervasive developmental disorders," by Montalbano R, Roccella M., Infant Neuropsychiatry, Department of Psychology, University of Palermo, Palermo, Italy mroccella@tin.it.

Autism in Plain English: The DSM-IV-TR Criteria Explained
The mental health bible used by professionals for diagnosing autism spectrum disorders in children is the Diagnostic and Statistical Manual of Mental Health Disorders, Fourth Edition, Text Revision (shortened to DSM-IV-TR).

This plain English interpretation of the DSM-IV-TR criteria for autism is not a diagnostic tool. It was written to help you better understand the constellation of symptoms that comprise autism. The 943-page DSM-IV-TR, published in 1994 by American Psychiatric Publishing Inc., lists 297 disorders and is set for revision in 2111. The DSM first recognized autism as a disorder during the same year Ronald Reagan was elected president — 1980.

The pervasive developmental disorders (PDD) heading in the DSM-IV-TR lists the diagnostic criteria for the five autistic or autism spectrum disorders. They include Autism, Childhood Disintegrative Disorder, Asperger Syndrome, Rett Syndrome, and pervasive developmental disorder-not otherwise specified, or PDD-NOS. Each of the PDD disorders has their own code and symptoms. For example, the diagnosis code for “autistic disorder” is 299. PDD is not a specific disorder; it only refers to the category that all of the disorders fall under. — The Early Intervention Network

Diagnostic Criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM IV):
Autistic Disorder - 299.00
Asperger's Disorder - 299.80
Rett's Disorder - 299.80
Childhood Disintegrative Disorder - 299.10
Pervasive Developmental Disorder Not Otherwise Specified (Including Atypical Autism) - 299.80

Diagnostic Criteria for Autistic Disorder - 299.00
The following criterion are from the 2000 Revision of the Diagnostic and Statistical Manual, Fourth Edition, Text Revision (DSM-IV-TR).

A. A total of Six (or more) items from (1), (2), and (3), with at least two from (1), and one each from (2) and (3).

1. Qualitative impairment in social interaction, as manifested by at least two of the following:
   • marked impairment in the use of multiple nonverbal behaviors such as eye-to-eye gaze, facial expression, body postures, and gestures to regulate social interaction
   • failure to develop peer relationships appropriate to development level
   • a lack of spontaneous seeking to share enjoyment, interest, or achievements with other people (e.g., by a lack of showing, bringing, or pointing out objects of interest)
   • lack of social or emotional reciprocity
2. Qualitative impairments in communication as manifested by at least one of the following:
   • delay in, or total lack of, the development of spoken language (not accompanied by an attempt to compensate through alterative modes of communication such as gesture or mine)
   • in individuals with adequate speech, marked impairment in the ability to initiate or sustain a conversation with others
   • stereotyped and repetitive use of language or idiosyncratic language
   • lack of varied, spontaneous make-believe play or social imitative play appropriate to developmental level
3. Restricted repetitive and stereotyped patterns of behavior, interests, and activities, as manifested by at least one of the following:
   • encompassing preoccupation with one or more stereotyped and restricted patterns of interest that is abnormal either in intensity or focus
   • apparently inflexible adherence to specific, nonfunctional routines or rituals
   • stereotypes and repetitive motor mannerisms (e.g., hand or finger flapping or twisting, or complex whole-body movements)
   • persistent preoccupation with parts of objects

B. Delays or abnormal functioning in at least one of the following areas, with onset prior to age 3 years: (1) social interaction, (2) language as used in social communication, or (3) symbolic or imaginative play.

C. The disturbance is not better accounted for by Rett’s Disorder or Childhood Disintergrative Disorder.

American Psychiatric Association. (2000). Diagnostic criteria for autistic disorder. In Diagnostic and statistical manual of mental disorders (Fourth edition---text revision (DSM-IV-TR). Washington, DC: American Psychiatric Association, 75.

Diagnostic Criteria for Asperger's Disorder - 299.80
The following criterion are from the 2000 Revision of the Diagnostic and Statistical Manual, Fourth Edition-Text (DSM IV-TR). Note: Asperger's Disorder is one of five specific Pervasive Developmental Disorders listed in the DSM IV-TR under the general heading of Pervasive Developmental Disorders.

1. Qualitative impairment in social interaction, as manifested by at least two of the following:
   • marked impairment in the use of multiple nonverbal behaviors such as eye-to eye gaze, facial expression, body postures, and gestures to regulate social interaction
   • failure to develop peer relationships appropriate to developmental level
   • a lack of spontaneous seeking to share enjoyment, interests, or achievements with other people (e.g., by a lack of showing, bringing, or pointing out objects of interest to other people)
   • lack of social or emotional reciprocity
2. Restricted repetitive and stereotyped patterns of behavior, interests, and activities, as manifested by at least one of the following:
   • encompassing preoccupation with one or more stereotyped and restricted patterns of interest that is abnormal either in intensity of focus
   • apparently inflexible adherence to specific, nonfunctional routines or rituals
   • stereotyped and repetitive motor mannerisms (e.g., hand or finger flapping or twisting, or complex whole-body movements)
   • persistent preoccupation with parts of objects
3. The disturbance causes clinically significant impairment in social, occupational, or other important areas of functioning.
4. There is no clinically significant general delay in language (e.g., single words used by age 2 years, communicative phrases used by age 3 years).
5. There is no clinically significant delay in cognitive development or in the development of age-appropriate self-help skills, adaptive behavior (other than in social interaction), and curiosity about the environment in childhood.
6. Criteria are not met for another specific Pervasive Developmental Disorder or Schizophrenia

American Psychiatric Association. (2000). Diagnostic criteria for autistic disorder. In Diagnostic and statistical manual of mental disorders (Fourth edition---text revision (DSM-IV-TR). Washington, DC: American Psychiatric Association, 84.

Diagnostic Criteria for Rett's Disorder - 299.80

Diagnostic criteria for Rett syndrome (RS) were developed by representatives of the International Rett Syndrome Association and the Centers for Disease Control for use in future clinical and epidemiological studies. Necessary criteria are: normal prenatal and perinatal period; normal psychomotor development through the first 6 months of life; normal head circumference at birth, with subsequent deceleration of head growth; loss of purposeful hand skills; severely impaired expressive and receptive language; apparent severe mental retardation; and gait apraxia and truncal apraxia/ataxia. Supportive criteria include breathing dysfunction, seizures, spasticity, scoliosis, and growth retardation. The diagnosis of RS is considered tentative until 2 to 5 years of age. The differential diagnosis includes other disorders associated with mental retardation, cerebral palsy, and seizure disorders. These diagnostic criteria for RS should foster reliable communication among investigators and enhance the epidemiological and clinical research of this important disorder.
— PMID: 2454607 [PubMed - indexed for MEDLINE]

1. All of the following:
   • apparently normal prenatal and perinatal development
   • apparently normal psychomotor development through the first 5 months after birth
   • normal head circumference at birth
2. Onset of all of the following after the period of normal development:
   • deceleration of head growth between ages 5 and 48 months
   • loss of previously acquired purposeful hand skills between ages 5 and 30 months with the subsequent development of stereotyped hand movements (e.g., hand-wringing or hand washing)
   • loss of social engagement early in the course (although often social interaction develops later)
   • appearance of poorly coordinated gait or trunk movements
   • severely impaired expressive and receptive language development with severe psychomotor retardation

Childhood Disintegrative Disorder - 299.10

1. Apparently normal development for at least the first 2 years after birth as manifested by the presence of age-appropriate verbal and nonverbal communication, social relationships, play, and adaptive behavior.
2. Clinically significant loss of previously acquired skills (before age 10 years) in at least two of the following areas:
   1. expressive or receptive language
   2. social skills or adaptive behavior
   3. bowel or bladder control
   4. play
   5. motor skills
3. Abnormalities of functioning in at least two of the following areas:
• qualitative impairment in social interaction (e.g., impairment in nonverbal behaviors, failure to develop peer relationships, lack of social or emotional reciprocity)
• qualitative impairments in communication (e.g., delay or lack of spoken language, inability to initiate or sustain a conversation, stereotyped and repetitive use of language, lack of varied make-believe play)
• restricted, repetitive, and stereotyped patterns of behavior, interests, and activities, including motor stereotypies and mannerisms
4. The disturbance is not better accounted for by another specific Pervasive Developmental Disorder or by Schizophrenia.

Pervasive Developmental Disorder Not Otherwise Specified (Including Atypical Autism) - 299.80
This category should be used when there is a severe and pervasive impairment in the development of reciprocal social interaction or verbal and nonverbal communication skills, or when stereotyped behavior, interests, and activities are present, but the criteria are not met for a specific Pervasive Developmental Disorder, Schizophrenia, Schizotypal Personality Disorder, or Avoidant Personality Disorder. For example, this category includes atypical autism --- presentations that do not meet the criteria for Autistic Disorder because of late age of onset, atypical symptomatology, or subthreshold symptomatology, or all of these.

The information presented herein does not necessarily reflect the position or policy of USAAA and no official endorsement should be inferred.