para>Symptom onset seen in children <3 years of age (except for childhood disintegrative disorder) á
Prevalence
- According to the Centers for Disease Control and Prevention (CDC), an estimated 1/68 to 1/175 children, depending on the community
- Among 6 to 17 years-aged children within the United States, in 2011 to 2012, there is found to be a 2% (1 in 50) parent-reported prevalence compared to 1.16% (1 in 86) as reported in 2007.
ETIOLOGY AND PATHOPHYSIOLOGY
- No single cause has been identified.
- General consensus: A genetic abnormality leads to altered neurologic development.
- No scientific evidence relating vaccines, such as vaccines for measles, mumps, or rubella (MMR), or thimerosal causing ASDs (3)[C]
- Pathophysiology is incompletely understood.
Genetics
- High concordance in monozygotic twins
- Increased recurrence risk (2-18%) in subsequent siblings
RISK FACTORS
Siblings of affected children have a five times greater risk of developing autism. Prevalence ranging from 2 to 8% á
GENERAL PREVENTION
- Early screening for early treatment means a better prognosis.
- Some ASDs are caused by genetic or chromosomal disorders.
- Economic costs
- An additional $17,000 to $21,000 is an estimated cost for raising an ASD child.
- Medical costs for those with ASD in 2011 were estimated to be 4 to 6 times, ranging from $2,191 to $11,590 per child (4)[B].
- An estimated lifetime cost of services for an individual with ASD in 2011 is $3.8 million (5)[C].
- Due to caretaker burden, family earnings are found to be 28% less among families with ASD compared to children without health conditions (6)[C].
COMMONLY ASSOCIATED CONDITIONS
- Mental retardation, ADHD, anxiety, depression, or obsessive behavior
- Phenylketonuria (PKU), tuberous sclerosis, fragile X syndrome, Angelman syndrome, and fetal alcohol syndrome (rare)
- Seizures (increased risk if severe mental retardation)
- Maternal use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy
DIAGNOSIS
HISTORY
- Impairment in social interaction
- Impairment in nonverbal behaviors such as eye-to-eye gaze, facial expression
- Unable to develop peer relationships
- Does not smile nor share emotions
- Loss of social or emotional reciprocity
- Communication impairment
- Delay or lack of development in language skills
- Inability to initiate or sustain conversation
- Stereotyped and repetitive use of language
- Preoccupation with parts of toys or body parts
- Repetitive and stereotyped patterns of behavior
- Excessively lines up toys or other objects
- Unusually attached to one particular toy or object
- Repetitive odd movements (toe walking, hand flapping)
- Adherence to specific routines or rituals
- Prenatal, neonatal, and developmental history
- Seizure disorder
- Family history of autism, genetic disorders, learning disabilities, psychiatric illness, neurologic disorders, genetic disorders, or mental retardation
- Commonly associated with sleep disorders
PHYSICAL EXAM
- Macrocephaly in 25%; head circumference growth peaks at age 6 months and begins to decline by 1 year.
- Dysmorphic features consistent with genetic disorder (fragile X syndrome)
- Hypotonia occurs in autism but should prompt imaging.
- Wood lamp skin exam to rule out tuberous sclerosis
DIFFERENTIAL DIAGNOSIS
- Other mental and CNS disorders
- Obsessive-compulsive disorder
- Elective mutism
- Language disorder/hearing impairment
- Intellectual disability/global developmental delay
- Stereotyped movement disorder
- Severe early deprivation/reactive attachment disorder
- Anxiety disorder
- Social communication disorder
- Developmental language disorder
DIAGNOSTIC TESTS & INTERPRETATION
- Checklist for Autism in Toddlers (CHAT) to screen for ASDs at 18 months of age. (To order: http://www.autism.org.uk/working-with/health/screening-and-diagnosis/checklist-for-autism-in-toddlers-chat.aspx)
- The Pervasive Developmental Disorders Screening Test-II (PDDST-II) to screen for ASDs beginning at 18 months
- Modified Checklist for Autism in Toddlers (M-CHAT) to screen for ASDs at 16 to 30 months
- Social Communication Questionnaire (SCQ) (formerly Autism Screening Questionnaire)-used with children age 4+ years-the gold standard diagnostic interview used in research studies
Initial Tests (lab, imaging)
- Lead and PKU screening
- Karyotype and DNA analysis (fragile X, PKU, tuberous sclerosis, and others)
- Metabolic testing if signs of
- Lethargy, limited endurance, unusual habits, hypotonia, recurrent vomiting and dehydration, developmental regression, or specific food intolerance
- MRI is useful only if focal neurologic symptoms.
Follow-Up Tests & Special Considerations
- Hearing tests: audiometry and brainstem auditory evoked response (BAERS)
- Comprehensive speech and language evaluation
- Evaluation by multidisciplinary team: includes a psychiatrist, neurologist, psychologist, speech therapist, and other autism specialists
- Intellectual level needs to be established and monitored, as it is one of the best measures of prognosis.
- Test used to follow autism are the following:
- Autism Behavior Checklist (ABC)
- Gilliam Autism Rating Scale (GARS)
- Childhood Autism Rating Scale (CARS)
- Autism Diagnosis Interview-Revised (ADI-R)
- Autism Diagnostic Observation Schedule-Generic (ADOS-G) Imaging
Diagnostic Procedures/Other
EEG if history of seizures or spells á
TREATMENT
GENERAL MEASURES
- Comprehensive structured educational programming of a sustained and intensive design, most commonly applied behavioral analysis therapy
- Core features of a successful education program
- High staff-student ratio 1:2, or less
- Individualized programming
- Specialized teacher training with ongoing evaluation of teachers and programs
- 25 hours a week minimum of specialized services
- A structured routine environment that emphasizes attention, imitation, communication, socialization, and play interactions (7)[C]
- Functional analysis of behavioral problems
- Transition planning and involvement of the family
- Currently no cure for ASDs. Early diagnosis and initiation of multidisciplinary intervention help enhance functioning in later life.
- Early intensive behavioral intervention (EIBI) involving treatment for 20 to 40 hours per week is a well-established treatments for ASD.
- School-based special education for older children
- Some evidence indicates social skill groups can improve social competence for some children and adolescents with ASD.
- Find alternative methods of communication: sign language; picture exchange communication system
MEDICATION
- Autism behavior issues should be managed with maximal behavioral management prior to medication.
- Medication directed at managing symptoms
First Line
- No true first-line medical therapy; medications used to treat targeted symptoms
- Stimulants (such as methylphenidate): Efficacious in treating concomitant symptoms of ADHD such as impulsiveness, hyperactivity, and inattention; however, the magnitude of response is less than in typically developing children and adverse effects are more frequent.
- SSRIs have limited evidence for autism. It has shown help in reducing ritualistic behavior and improving mood and language skills. Initial choice for anxiety and depressive mood (8)[B]
- Risperidone has shown short-term efficacy for treatment for irritability, repetitious behaviors, and social withdrawal (9)[B]. Aripiprazole has shown efficacy for treating short-term irritability, hyperactivity, and repetitive movements (10)[B].
- Melatonin used for patients with concomitant sleep disorders
Second Line
- Vitamin B6 and magnesium: inconclusive evidence in improving behavior, speech, and language of children with ASD (11)[C]
- Tricyclic antidepressants have limited and conflicting evidence of effect (12)[B].
ISSUES FOR REFERRAL
- Refer early to
- Early learning for evaluation of behavior and language, genetic counseling, and audiology
- Consider referrals to psychiatry, ophthalmology, otolaryngology, neurology, and nutrition (13).
- Refer family members to parent support groups and respite programs.
COMPLEMENTARY & ALTERNATIVE MEDICINE
- Parent-mediated early intervention for young children with autism spectrum has sufficient evidence of benefit in child outcomes related to language understanding and severity of autism characteristics (14)[A].
- Music therapy has been shown to improve communication skills in autistic patients; however, more research is needed (15)[C].
- "Theory of mind,"Ł or related skills, can be taught to ASD patients, but further research is needed (16)[C].
- No evidence to support use of auditory integration therapy or other sound therapies as an effective treatment for ASD (17)[B].
- No evidence to support acupuncture for treatment of ASD (6)[C].
- IV secretin and pharmaceutical chelation has shown no evidence of efficacy and is not currently recommended as a treatment for ASD (18,19)[C].
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Patient Monitoring
- Constant monitoring by caregivers
- Reevaluation every 6 to 12 months by physician for seizures, sleep and nutritional problems, and prescribed medical management
- Intellectual and language testing every 2 years in childhood
DIET
- Gluten- and casein-free diets: Current evidence for efficacy is poor (20)[C].
- Omega-3 fatty acids supplementation has not been found to improve outcomes (21)[C].
PROGNOSIS
- Beginning treatment at a young age (2 to 4 years) results in better outcomes.
- Prognosis is closely related to initial intellectual abilities, with only 20% functioning above the mentally retarded level.
- Communicative language development before 5 years is also associated with a better outcome.
- The general expected course is for a lifelong need for supervised structured care.
COMPLICATIONS
- Increasing incidents of seizure disorders in up to 1 in 4 children
- Increased risk for physical and sexual abuse
- With pica, increased risk of lead poisoning
- Limited variety of food consumed due to dietary obsessions
- Increased risk for GI symptoms, including weight abnormalities and abnormal stool patterns
REFERENCES
11 Autism and Developmental Disabilities Monitoring Network Surveillance Year 2008 Principal Investigators; Centers for Disease Control and Prevention. Prevalence of autism spectrum disorders-Autism and Developmental Disabilities Monitoring Network, 14 sites, United States, 2008. MMWR Surveill Summ. 2012;61(3):1-19.22 Blumberg áSJ, Bramlett áMD, Kogan áMD, et al. Changes in prevalence of parent-reported autism spectrum disorder in school-aged U.S. children: 2007 to 2011-2012. Natl Health Stat Report. 2013;(65):1-11.33 Demicheli áV, Rivetti áA, Debalini áMG, et al. Vaccines for measles, mumps and rubella in children. Cochrane Database Syst Rev. 2012;(2):CD004407.44 Lavelle áTA, Weinstein áMC, Newhouse áJP, et al. Economic burden of childhood autism spectrum disorders. Pediatrics. 2014;133(3):e520-e529.55 Ganz áML. The lifetime distribution of the incremental societal costs of autism. Arch Pediatr Adolesc Med. 2007;161(4):343-349.66 Cidav áZ, Marcus áSC, Mandell áDS. Implications of childhood autism for parental employment and earnings. Pediatrics. 2012;129 (4):617-623.77 Cheuk áDK, Wong áV, Chen áWX. Acupuncture for autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2011;(9):CD007849.88 Williams áK, Brignell áA, Randall áM, et al. Selective serotonin reuptake inhibitors (SSRIs) for autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2013;(8):CD004677.99 Jesner áOS, Aref-Adib áM, Coren áE. Risperidone for autism spectrum disorder. Cochrane Database Syst Rev. 2007;(1):CD005040.1010 Ching áH, Pringsheim áT. Aripiprazole for autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2012;(5):CD009043.1111 Nye áC, Brice áA. Combined vitamin B6-magnesium treatment in autism spectrum disorder. Cochrane Database Syst Rev. 2005;(4):CD003497.1212 Hurwitz áR, Blackmore áR, Hazell áP, et al. Tricyclic antidepressants for autism spectrum disorders (ASD) in children and adolescents. Cochrane Database Syst Rev. 2012;(3):CD008372.1313 Reichow áB, Steiner áAM, Volkmar áF. Social skills groups for people aged 6 to 21 with autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2012;(7):CD008511.1414 Oono áIP, Honey áEJ, McConachie áH. Parent-mediated early intervention for young children with autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2013;(4):CD009774.1515 Geretsegger áM, Elefant áC, M Âssler áKA, et al. Music therapy for people with autism spectrum disorder. Cochrane Database Syst Rev. 2014;(6):CD004381.1616 Fletcher-Watson áS, McConnell áF, Manola áE, et al. Interventions based on the Theory of Mind cognitive model for autism spectrum disorder (ASD). Cochrane Database Syst Rev. 2014;(3):CD008785.1717 Sinha áY, Silove áN, Hayen áA, et al. Auditory integration training and other sound therapies for autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2011;(12):CD003681.1818 Williams áK, Wray áJA, Wheeler áDM. Intravenous secretin for autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2012;(4):CD003495.1919 James áS, Stevenson áSW, Silove áN, et al. Chelation for autism spectrum disorder (ASD). Cochrane Database of Syst Rev. 2015;(5):CD010766.2020 Millward áC, Ferriter áM, Calver áS, et al. Gluten- and casein-free diets for autistic spectrum disorder. Cochrane Database Syst Rev. 2008;(2):CD003498.2121 James áS, Montgomery áP, Williams áK. Omega-3 fatty acids supplementation for autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2011;(11):CD007992.
ADDITIONAL READING
- Reichow áB, Barton áEE, Boyd áBA, et al. Early intensive behavioral intervention (EIBI) for young children with autism spectrum disorders (ASD). Cochrane Database Syst Rev. 2012;(10):CD009260.
- Vriend áJL, Corkum áPV, Moon áEC, et al. Behavioral interventions for sleep problems in children with autism spectrum disorders: current findings and future directions. J Pediatr Psychol. 2011;36(9):1017-1029.
SEE ALSO
Algorithm: Intellectual Disability á
CODES
ICD10
- F84.0 Autistic disorder
- F84.5 Asperger's syndrome
- F84.3 Other childhood disintegrative disorder
- F84.9 Pervasive developmental disorder, unspecified
- F84.8 Other pervasive developmental disorders
ICD9
- 299.00 Autistic disorder, current or active state
- 299.80 Other specified pervasive developmental disorders, current or active state
- 299.10 Childhood disintegrative disorder, current or active state
- 299.90 Unspecified pervasive developmental disorder, current or active state
- 299.91 Unspecified pervasive developmental disorder, residual state
- 299.01 Autistic disorder, residual state
- 299.81 Other specified pervasive developmental disorders, residual state
- 299.11 Childhood disintegrative disorder, residual state
- 299.81 Other specified pervasive developmental disorders, residual state
SNOMED
- 408856003 autistic disorder (disorder)
- 23560001 Asperger's disorder (disorder)
- 71961003 Childhood disintegrative disorder
- 35919005 pervasive developmental disorder (disorder)
CLINICAL PEARLS
- ALARM mnemonic from the American Academy of Pediatrics (AAP)
- ASD is prevalent (screen ALL children between 18 and 24 months).
- Listen to parents when they feel something is wrong.
- Act early: Screen all children who fall behind in language and social developmental milestones (use early learning to help with evaluation).
- Refer to multidisciplinary teams (speech and language evaluation, genetic screening, social support groups).
- Monitor support for patient and families.