Pocket Pediatrics: The Massachusetts General Hospital for Children Handbook of Pediatrics (Pocket Notebook Series), 2 Ed.

AUTISM SPECTRUM DISORDER (ASD)

(Pediatrics 2007;120:1183; Pediatr Rev 2008;29:86; BMJ 2011;343:d6238)

Introduction

• Neurodevelopmental condition with criteria currently undergoing revision; see below

• ASD includes autistic disorder, Asperger disorder, and pervasive developmental disorder – not otherwise specified – these, plus childhood-disintegrative disorder, likely to be merged into single category of ASD. Rett syndrome would be separate

• CDC: 1 in 88 US children identified, male:female ratio <5:1 (www.cdc.gov/autism)

• Etiology unknown; apparent genetic and nongenetic risk factors include affected parent or sibling, ↑ parental age, genetic/chromosomal conditions like fragile X or tuberous sclerosis; in utero exposure to meds like valproate and SSRIs; prematurity and LBW

• Associated medical problems: Seizures in 20–35%, pica, constipation, feeding problems, and sleep disturbances (BMJ 2011;343:d6238)

• AAP recs early ID (Pediatrics 2007;120:1183)

• Early intervention improves outcomes (Pediatrics 2010;125(1):e17)

• Comprehensive eval for identifiable etiology: See below

• Genetic counseling for parents: ≥4–7% recurrence risk in younger/future sib

Criteria for Dx of Autism (DSM-IV-TR 2000.75) (*Criteria applicable to pt <3 yo)

• Impairment in reciprocal social interaction

• *Impaired nonverbal behavior (eye contact, facial express, posture, and gestures)

• *Absent seeking interaction (no pointing, showing, or bringing objects of interest)

• *Lack of social or emotional reciprocity

• Lack of peer relationships

• Impairment in communication

• *Delay or lack of spoken language (w/o compensation via gestures)

• If w/ adeq speech, inability to initiate or sustain a conversation

• Stereotyped and repetitive use of language; lack of make-believe or imitative play

• Repetitive patterns of behavior, interest, and activities

• Intense preocc w/ stereotyped interest; persistent preocc w/ parts of objects

• Inflexible adherence to specific routines or ritual’s

• Repetitive motor mannerisms (hand-flapping, whole-body movements)

Proposed DSM-V Revisions: Must meet criteria from A, B, C, and D

(www.dsm5.org/ProposedRevision/Pages/proposedrevision.aspx?rid=94)

• Persistent deficits in social communication & interaction, manifest by all 3

• Deficits in social-emotion reciprocity (anml social approach, failure of nml back & forth conversation, lack of initiation of social interaction)

• Deficits in nonverbal communicative behaviors used for interaction (poorly integrated verbal/nonverbal communication, abnml eye contact & body language, deficits in understanding/use of nonverbal comm, lack of facial expression/gesture)

• Deficits in developing/maintaining relationships (difficulties with adjusting behavior to social context, difficulties in sharing imaginative play, lack of interest in people)

• Restricted, repetitive patterns of behavior, interests, or activities, manifest by 2 of

• Stereotyped or repetitive speech, motor movements, use of objects

• Excess adherence to routines, ritualized patterns of behavior, resistance to change

• Highly restricted fixated interests that are abnml in intensity and focus

• Hyper-/hyporeactivity to sensory input or fascination with sensory aspects of env

• Symptoms must be present in early childhood

• Symptoms limit and impair everyday functioning

• DSM 5 likely to include all 3 diagnoses under ASD only, subdivided into severity levels

Surveillance and Screening (Pediatrics 2007;120:1183)

• AAP recs surveillance at each well visit (risk factors include sib with autism, pediatrician concern, and parental or other caregiver concern), also screening at 18 and 24 mo with autism-specific screening tool (i.e., M-CHAT for toddlers, SCQ for children >4 yo)

• If autism suspected (two or more risk factors, positive or concerning results on autism screening tool or eval of communication and social skills), refer to autism dx clinic, early intervention (<3 yo) or education services/program (>3 yo), and audiology

• Absolute indications for immed eval: “Red Flags” (Neurology 2000;55:468)

• No babbling, pointing, or other gestures by 12 mo; no single words by 16 mo

• No 2-word spontaneous phrases (not just echolalia) by 24 mo

• Any loss of any language or social skills at any age

• Siblings of children with ASD should undergo heightened surveillance as above

Diagnostic Studies (Pediatrics 2007;120:1183; BMJ 2011;343:d6238)

• Hearing tests (behav audiometrics, middle ear fxn, and electrophys procedures)

• Lead level, Hgb (periodic screening if pica)

• Detailed history (esp family), physical for dysmorphisms, Wood’s lamp exam

• Genetic testing (karyotype – either high res or with microarray; chromosomal microarray) and DNA testing for fragile X if pt has GDD/MR, MECP2 testing in girls if concern for Rett

• Targeted studies (selective metabolic testing, EEG, MRI) considered if cyclic vomiting, lethargy, seizures, dysmorphic or coarse facial features, MR, hypopigmented macules, or if newborn screening is inadequate or unavailable

• Consider referral to neurology, genetics, child psych or developmental pediatrician as indicated. Include speech therapists, OT, special ed/IEP, SW

• Ddx includes Down, CHARGE assoc, fragile X, tuberous sclerosis, PKU, fetal alcohol syndrome, Angelman, Rett, and Smith–Lemli–Opitz syndromes

Treatment Approaches: Early initiation is imperative, best outcomes

• Educational approaches: Early start Denver model and TEACCH (improve cognitive performance, language skills, adaptive behavior skills)

• Disruptive behavior best targeted with functional behavioral assessment (IDs modifiable behaviors & teaches new skills and desirable behaviors)

• Speech/language tx (promote functional communication), social skill instruction, occupational therapy

• Tx of psychiatric comorbidities – best data for risperidone, aripiprazole, methylphenidate

• No 2-word spontaneous phrases (not just echolalia) by 24 mo

• Any loss of any language or social skills at any age

• Siblings of children with ASD should undergo heightened surveillance as above

Diagnostic Studies

• Hearing tests (behav audiometrics, middle ear fxn, and electrophys procedures)

• Lead level, Hgb (periodic screening if pica)

• Genetic testing (karyotype) and DNA analysis for fragile X if parents w/ MR, MECP2 testing in young girls if concern for Rett

• Targeted studies (selective metabolic testing, EEG, MRI) considered if cyclic vomiting, lethargy, seizures, dysmorphic or coarse facial features, MR, hypopigmented macules, or if newborn screening is inadequate or unavailable

• Consider referral to neurology, genetics, child psych, or a developmental pediatrician. Include speech therapists, OT, special ed/IEP, SW

• Ddx includes Down, CHARGE assoc, fr*agile X, tuberous sclerosis, PKU, fetal alcohol syndrome, Angelman, Rett, and Smith–Lemli–Opitz syndromes

Treatment Approaches: Early initiation is imperative for best outcomes

• Educational approaches: Early start Denver model and TEACCH (improve cognitive performance, language skills, adaptive behavior skills)

• Disruptive behavior best targeted with functional behavioral assessment (IDs modifiable behaviors & teaches new skills and desirable behaviors)

• Speech/language tx (promote functional communication), social skill instruction, occupational therapy

• Tx of psychiatric comorbidities – best data for risperidone, aripiprazole, methylphenidate