1. Rett Syndrome Childhood Disintegrative Disorder Pervasive Developmental Disorder Not Otherwise Specified (PDD- NOS) Ivette, Izumi, Richard

2. Pervasive Developmental Disorders Rett Syndrome: Normal development for five months to four years, followed by regression and intellectual disabilities (mental retardation); much more prevalent in females Childhood Disintegrative Disorder: Normal development for at least two and up to 10 years, followed by significant loss of skills: much more prevalent in males Pervasive Developmental Disorder Not Otherwise Specified: persons who display behaviors typical of autism but to a lesser degree and/or with an onset later than three years of age

3. RS: Diagnostic Criteria (DSM4-TR) 1.apparently normal prenatal and perinatal history 2.psychomotor development largely normal through the first six months or may be delayed from birth 3.normal head circumference at birth 4.postnatal deceleration of head growth in the majority of patients 5.loss of achieved purposeful hand skill between ages six months and 2.5 years 6.stereotypic hand movements such as hand wringing/squeezing, clapping/tapping, mouthing and washing/rubbing automatisms 7.emerging social withdrawal, communication dysfunction, loss of learned words, and cognitive impairment 8.impaired (dyspraxic) or failing locomotion

4. RS: Causes&Prevalence Causes -Mutation in the MECP2 gene -Mutation in other parts of gene Prevalence -1 in 15,000 live births -Much more in females

5. CDD: Diagnostic Criteria (DSM4-TR) A. 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. B. 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 C. Abnormalities of functioning in at least two of the following areas: 1.qualitative impairment in social interaction 2.qualitative impairments in communication 3.restricted, repetitive, and stereotyped patterns of behavior, interest, and activities, including motor stereotypes and mannerisms D. The disturbance is not better accounted for by another specific Pervasive Developmental Disorder or by Schizophrenia

6. CCD: Causes&Prevalence Causes Unknown but it has been linked to neurological problems Prevalence -1 in 50,000 live births -Much more in males

7. PDD-NOS: Diagnostic Criteria (DSM4- TR) This category should be used when there is a severe and pervasive impairment in the development of reciprocal social interaction associated with impairment in either verbal or nonverbal communication skills or with the presence of stereotyped behavior, interests, and activities, 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 at onset, atypical symptomatology, or subthreshold symptomatology, or all of these.

8. PDD-NOS : Causes&Prevalence Causes Unknown but it has been linked to abnormalities of brain structure and function Prevalence -6-14 per 10,000 children younger than 10 years -More in males

9. Strategies for students with Rett Syndrome http://www.lburkhart.com/hand_Rett_Sy ndrome_7_07.pdf

10. References http://www.ninds.nih.gov/disorders/rett/detail _rett.htm http://www.rettsyndrome.org http://www.asaoakland.org/pdd_nos.htm http://journals.cambridge.org/action/displayA bstract?fromPage=online&aid=255439 http://www.cdc.gov/ncbddd/autism/overview_ diagnostic_criteria.htm http://www.lburkhart.com/hand_Rett_Syndro me_7_07.pdf