Pervasive Developmental Disorders

Nursing 864September 24, 2009

Autism Spectrum DisordersAutismAsperger’s SyndromePDD, NOS

Rett’s disorder Childhood Disintegrative Disorder

Autism Spectrum Disorders

PrevalenceApproximately 1/150 children4.3 : 1 ratio males to females Increase in prevalence

Causes Better assessment and diagnostic tools Improved recognition by health care providers Increased public awareness

Etiology

Genetic Multiple genes involved Rate of occurrence in siblings 2-8% Monozygotic twins – 60%

Syndromes and Related Health Problems Occurs in less than 10% Fragile X Epilepsy Tuberous sclerosis Fetal alcohol syndrome Mental retardation occurs in approximately 70% of children Increased rate of perinatal complications in the mother

AutismDiagnosis – DSM- IV-TR criteria Qualitative impairment in social interaction (at least 2)

Impaired nonverbal behaviors Failure to develop peer relationships as same age level Lack of seeking to enjoy interests or achievement

Qualitative impairment in communication (at least one) Delay or lack of spoken language Impaired ability to initiate or sustain conversation Stereotyped and repetitive use of language Lack of varied or spontaneous play

Restricted repetitive and stereotyped patterns of behavior, interests and activities (at least one) Preoccupied with one or more stereotyped or restricted interest Inflexible to nonfunctional routines or rituals Stereotyped or repetitive movements

Impaired Social Interaction

Low rates or no initiation of social interaction Little interest in other children Trouble sustaining social interactions Little shared interest No joint attention Does not imitate Does not enjoy social games No social smile Little shared interest Poor eye contact and rarely looks for reaction

Communication Deficits

Delay in language development – principal criteria for diagnosis

Difficulty putting meaningful sentences together Nonverbal communication impaired

Inappropriate gestures No response to name called (seems deaf) Difficulty perceiving themes or intent Does not point to request (proto-imperative) Does not point to interest (proto-declarative) Echolalia Confused pronouns Very literal and concrete

Restricted Range of Interests/Stereotyped Preoccupation with topics or intense interest Preoccupation with sensory experiences Repetitive movements Manipulate toys in ritualistic manner Monotonous play Spin, bang, line up toys Rocking motions Spinning body Flap hands Taste or smell unusual objects Rigid with rules and resistant to transitions

Asperger’s syndrome

Asperger’s syndrome Qualitative impairment in social interaction (at least

two) Restricted repetitive and stereotyped pattern of

behavior, interests and activities (at least one) No clinically significant language delay No clinically significant delay in cognitive

development, self-help skills or adaptive behavior (other than social interaction)

PDD, NOS

Severe impairment in the development of reciprocal social interaction Impaired verbal or nonverbal communication skills Presence of stereotyped behavior, interests, and

activities Criteria are not met for other PDD

Late Onset Atypical symptomatology Subthreshold symptomatology

Childhood Disintegrative Disorder

Rare disorder Occurs in less than 5/10,000

Occurs after at least two years of normal development Generally is diagnosed around 4-5 years of age. Occurs more frequently in males Along with regression in social skills and communication,

there is regression in motor skills Etiology

Predisposition to genetic and environmental influences Prognosis guarded

Rett’s Syndrome

Almost exclusively in females Typically neurogenerative arrest Etiology - Gene MECP2 located on the X chromosomes Early clinical features

Deceleration of head growth Period of developmental stagnation is followed by a period of

regression Loss of purposeful hand skills and oral language Development of hand stereotypies and gait dyspraxia

Prognosis – 70% 35 year survival rate

Theory of Mind

The ability to understand the thoughts and intentions of others (mental states)

Perspective taking of others It can determine how an individual acts and

reactLack of ability or reduced ability in Asperger’s

and Autistic disorder

Sally-Anne test (Theory of Mind) (Wimmer and Perner, 1983)

In the presence of the child, the experimenter uses two dolls, "Sally" and "Anne". Sally has a basket; Anne has a box.

The experimenters show a skit: Sally puts a marble in her basket and then leaves the

scene. While Sally is away and cannot watch, Anne takes the

marble out of Sally's basket and puts it into her box. Sally then returns.

The children are asked where they think she will look for her marble.

Children are said to "pass" the test if they understand that Sally will most likely look inside her basket before realizing that her marble isn't there.

Pathophysiology

Neuroanatomical Factors Enlargement of gray and white matter cerebral volumes

Increased rate of head circumference emerges at about 12 months of age

Increased volumes in the temporal, parietal and occipital region

No differences in size in frontal lobe or cerebellum Possible mechanisms

Increased neurogenesis Decreased neuronal death Increased production of nonneuronal brain tissue

Pathophysiology

Neurotransmitters Increased brain-derived neurotrophic factor

and other neurotrophins Age –related serotonin synthesis capacity

These may contribute to abnormal brain growth and organization

Screening and Diagnosis

Group of symptoms Behavioral No medical tests Screening and diagnosis involved clinical judgment Diagnosis requires presence of severe and pervasive

impairment across domains Not every socially awkward or eccentric child has ASD, but

never wait and see Targeted developmental screening – 9,18 & 30 months Autism specific screening – 18 and 24 months

Screening Tools

Level 1 Modified Checklist for Autism in Toddler (M-CHAT)

Screen as young as 18 months Critical items

Peer interest Pointing Joint attention Shared interest Imitation Responds to Name

Screening Tools

Level 2Child Autism Rating Scale (CARS)Gilliam Autism Rating Scale (GARS)Gilliam Asperger’s Disorder Scale (GADS)Social Communication Questionnaire (SCQ)

Diagnostic Tools

Level 3Autism Diagnostic Observation Scale (ADOS)Autism Diagnostic Interview – Revised (ADIR) Preschool Language Scales (IV) – by SLP Adaptive Ratings (i.e., Vineland) Cognitive Testing

Diagnostic Evaluation

Multidisciplinary Team Developmental Pediatrics, Psychology, Speech,

Genetics, and Education Medical/Developmental/Behavioral History Structured Interview Behavior Ratings Scales Structured Direct Observation Direct Interaction/Teaching Functional Assessment Standardized Testing (Speech, Genetics, Psychology)

Other Diagnostic Tests

Used primarily for children with cognitive impairment MRI – with MR High-resolution chromosomes

Analysis of the number and structure of the chromosomes

Fragile X DNA Microarray

Investigates the expression levels of thousands of genes simultaneously.

Empirically Supported Treatments

Early Intensive Behavioral Intervention Based on Applied Behavior Analysis

Systematic modifications of the environment based on principles of behavior identified through experimental analysis

Focuses on the purpose or the function of the behavior

Involves changing antecedents and consequences to change behavior

Uses principals of operant conditioning

Incidental TeachingTo help improve or elaborate language skillsTeaching occurs when child initiates

communicationMust create communication temptationsPrompts help the child be successful Involves labeling and describing that occurs in

the adult-child interaction

Picture Exchange Communication System (PECS)Augmentative communicationPicture exchange for teaching communication

skillsEmphasizes teaching functional languageNo evidence of children losing established

speech

Discrete Trial TrainingPrecise teaching interactions that emphasize

potent and frequent reinforcing consequencesEach skill is taught separately Prompting helps insure responding and

successEmphasis on high rate of teaching

interactions

Naturalistic Teaching ProceduresTeaching procedures that are embedded in

their natural activitiesEnhances the spontaneity and generalization

of language, social and play skillsDemonstrated to be beneficial for children

who are developmentally delayed or disadvantaged

Guidelines for Treatment

Combination of ABA proceduresBest outcome between ages 2-5Best outcome for 25 hours or more per weekBest outcome when functional communication

is established by age 5

Comorbid Conditions

Behavioral ADHD Sleep disturbance Disruptive behaviors

Temper tantrums Aggression Self-injury

Anxiety Generalized, intense worries Obsessions and compulsions

Neurologic Seizures – 20-35% Hypotonia Gait Abnormalities Microcephaly – associated with co-existing structural

brain malformations Macrocephaly

Orthopedic Toe walking

NutritionRestricted food choicesRituals Poor motor skillsNo evidence of dietary restrictions helpful in

treatment (gluten or casein)Pica

Monitor lead levels

Medication Management

Atypical Antipsychotics - Aggression Risperdal – Only FDA approved medication for

children with autism Abilify

Stimulants- ADHD Alpha-adrenergic antagonists –

Clonidine & Tenex – impulsivity and sleep

SSRI’s - anxiety

Parent Counseling

Safety Nutrition Advocacy in the School System – IEP Bullying Parenting Stress Siblings

Resources

Autism Action Partnership www.autismaction.org

PTI Nebraska www.pti-nebraska.org

First Signs www.firstsigns.org

National Autism Association http://www.nationalautismassociation.org/

Munroe-Meyer Institute Center for Autism Spectrum Disorders 559-2441