The Clinician’s Guide to Autism
2014; American Academy of Pediatrics; Volume: 35; Issue: 2 Linguagem: Inglês
10.1542/pir.35.2.62
ISSN1529-7233
AutoresJohn W. Harrington, Korrie Allen,
Tópico(s)Family and Disability Support Research
ResumoAfter completing this article, readers should be able to:Autism spectrum disorder (ASD) includes a continuum of neurodevelopmental disorders characterized by deficits in social communication and interactions, along with restrictive, repetitive patterns of behaviors, interests, and activities. (For this article, ASD and autism are used interchangeably.) Pediatric clinicians can significantly affect the outcome of children with ASD by making an early diagnosis and providing referral for evidenced-based behavioral treatment. By recognizing the early signs and symptoms of autism and addressing common comorbid concerns, such as sleep problems, gastrointestinal problems, seizures, and behavioral and psychiatric concerns, as well as being aware of complementary and alternative medicine (CAM) therapies, clinicians can provide a more comprehensive medical home for their patients and parents.Recent data from the National Survey of Children's Health from 2011–2012, which estimates parent-reported ASD diagnoses for school-aged children, placed the current prevalence of autism at 2%. (1) However, the Centers for Disease Control and Prevention's Autism and Developmental Disabilities Monitoring Network, which requires more definitive diagnostic testing, estimates the prevalence of ASD in the United States at 1 in every 88 children. Because males outnumber females 4 to 1, this translates into an incidence of 1 in 54 males and 1 in 252 females. (2) This recent estimated prevalence rate represents an increase of 23% compared with the 2006 estimate of 1 in 110 children. With the steady increase during the past 2 decades, ASD has become an urgent public health concern. A recent study by Hallmayer et al (3) of the largest collection of fraternal and identical twins revealed that genetic and environmental factors likely have an equal effect on determining an autism diagnosis with sibling risk rates at or above 25%.The increase in diagnosis of autism during the last 20 years has raised public concern and questions on possible causes. Reasons for the increase include diagnostic substitution, broadening of the definition of ASD, and better screening and ascertainment. Diagnostic substitution assumes that children previously were diagnosed only as being developmentally delayed and/or intellectually disabled and not appropriately diagnosed as having an ASD. Monitoring networks have allowed multiple records (clinicians and schools) to be reviewed, which has led to better ascertainment of children diagnosed as having an ASD. In addition, concerted efforts by multiple sources (American Academy of Pediatrics, Autism Speaks, and FirstSigns.org) to improve screening at a younger age have had an effect. Finally, the broader definition of autism, now referred to as ASD has allowed more cases of ASD to be diagnosed. The most recent report from the Centers for Disease Control and Prevention indicates that the biggest increase in cases is among the higher-functioning patients with less severe disease and in African American and Hispanic populations. (1)(2)Commonly, the first sign that alerts a pediatric clinician to a child with possible autism is a deficit in communication, manifested by a delay in or abnormal use of language, at approximately ages 18 to 24 months. A child with autism may initially be mute, have a significant delay in language acquisition, or have a regression in language. If the child is speaking, he or she may only exhibit echolalia, repeating words and phrases previously heard. In some instances, children with autism may develop language normally and be quite verbose, but they only speak tangentially about their specific interests without any concern about the listener's response. Children with autism may also have trouble modulating their vocal tone (ie, monotone), with little inflection in their voice. Because of these deficits in language and reciprocity, many children tend to have an inability to initiate or sustain a conversation with others.Social reciprocity is the give and take of social interaction and requires the child to have the ability to recognize another person's perspective. Children with autism have difficulty with social reciprocity; thus, they have trouble establishing relationships with same-aged peers. This inability to socially share or reciprocate implies that a child with autism may not empathize well. These social deficits impair one's ability to maintain joint attention (ability to attend to an activity with another person), read body language, and respond to nonverbal cues. A red flag for these difficulties is an inability to point to a desired object at 18 months (protoimperative pointing), but even more important is whether the child uses pointing to draw something to the attention of another, referred to as protodeclarative pointing. Children with autism may pull their caregiver by the hand to a desired object by hand guiding. Direct eye contact may be difficult and avoided by children with autism. A study from Yale compared the eye gaze pattern of children with autism and neurotypical peers during a video simulation of play with an adult. Children with autism tended to spend more time looking at the adult's mouth rather than the eyes, whereas the neurotypical peers spent little time looking at the mouth and most of the time looking at the eyes of the speaker. (4)The repetitive and restrictive behaviors noted in autism can be the most isolating symptoms of the disorder. Often children strongly desire a rigid routine and are extremely upset if there is deviation from the routine. This reliance on maintaining a nonfunctional routine to avoid conflict can make a family's life stressed. Repetitive motor movements, such as hand flapping or an intense preoccupation with parts of an object, like spinning wheels on a toy car, highlight these behaviors. Children with autism may also have difficulty with onset or maintenance of sleep, as well as restricted food preferences, and hypersensitivity or hyposensitivity to any of the 5 senses. Repetitive and restrictive behaviors along with these sensory issues have gained new prominence and hallmark some of the classification changes recently implemented in the Diagnostic Statistical Manual of Mental Disorders, Fifth Edition (DSM-5).There had been some debate about the upcoming changes to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). The newer DSM-5 was accepted and published in May 2013. The DSM-5 merges communication and social interaction behaviors into one symptom category and increases the importance of the repetitive and restrictive behavior into the requirements for a diagnosis of an ASD. The DSM-5 also allows the use of co-occurring diagnoses to exist with autism, whereas before a child under the DSM-IV could not have both autism and attention-deficit/hyperactivity disorder (ADHD). To obtain more specifics concerning the diagnostic features, differential diagnosis, and comorbidities, the reader is referred to the full publication of the DSM-5.The DSM-5 criteria are listed below (reprinted with permission from the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition [Copyright 2013], American Psychiatric Association).To diagnose an ASD from the DSM-5, a child will need to meet the criteria in A, B, C, D, and E:Once the diagnosis of ASD is made, the DSM-5 provides a severity level rating that can be used to help grade the level of functioning for the child. As stated in the criteria for diagnosis, the severity level rating is based on both social communication impairments and restricted, repetitive patterns of behavior but should be rated separately. This process is outlined in Table 1.It may be tempting to use this severity grading of function to determine eligibility of services for children; however, severity may vary over time and in certain situations, and therefore providing services should be decided on an individual level. Table 2 summarizes specific changes to the DSM-IV in the DSM-5.The changes in the DSM-5 may help to clarify the diagnostic process for autism, but some opponents to this change are worried that it will decrease the overall incidence by only recognizing the most severely affected, thus overlooking children who may benefit from autism services. Proponents believe that this will not happen. However, in recent studies using the DSM-5 criteria vs the DSM-IV, up to 48% fewer toddlers would be diagnosed as having autism. (5) Reconciling the new changes to the DSM will be challenging in the next few years, when considering that the previous increase in the incidence of autism during the last 2 decades is still not completely understood.It is well known that certain genetic disorders (eg, fragile X syndrome, neurofibromatosis, and tuberous sclerosis) are more likely to be associated with autism and should be considered when making a diagnosis of ASD (Table 3). In addition, with refined genetic techniques, such as comparative genomic hybridization microarrays, whole genome linkage, and gene association studies, researchers have found "hot spots" on almost every chromosome that can coincide with either a specific single-nucleotide polymorphism or copy number variant. (6) Interestingly, it is not always the gene but the intervening sequences between genes (introns) and how they are methylated that play a critical role in how genes are turned on and off. However, even with an advanced ability to view up to 10,000 base pairs on the genome, approximately 75% of children diagnosed as having autism have no measurable genetic abnormality when rigorously tested. (7)Without a consistent genetic association for autism, a search for a possible environmental cause has led some to consider implicating vaccines because these are given throughout early infancy and at the same time when children are diagnosed as having autism. Initially, the measles-mumps-rubella vaccine was linked as a cause of autism through a small, poorly conceived case series by a British gastroenterologist named Andrew Wakefield. This report was later retracted by Lancet when it was found to be tainted by inappropriate recruitment and bias. When the measles-mumps-rubella vaccine link was disproven, a recycled theory concerning mercury as a preservative (thimerosal) in multidose vial vaccines became popular as a cause of autism, which was also subsequently disproven. Furthermore, the manufacturers removed thimerosal from their vaccines. Unfortunately, some parents and antivaccine websites still try to manipulate temporal data into causality. It is therefore important for pediatric clinicians to be aware of this misguided information and to be able to counter this argument with the multitude of studies that have disproven any causal association between vaccines and autism. (8) It is important to make parents aware of the risks of not vaccinating. If a parent is steadfastly against vaccinating their child for fear of causing autism, even after an exhaustive use of evidenced-based data to the contrary, then the American Academy of Pediatrics (AAP) recommends that they fill out a refusal to vaccinate form (http://www2.aap.org/immunization/pediatricians/pdf/RefusaltoVaccinate.pdf).Historically, certain exposures and environmental factors were associated with an increased risk of autism: rubella infection, exposure to thalidomide or valproic acid in the first trimester, and untreated phenylketonuria. A search for additional environmental factors was launched in California in 2000, called the Childhood Autism Risk from Genetics and Environment. Some factors that have been established as incurring risk include prematurity, twins or multiple pregnancy, and advanced maternal or paternal age at conception. A recent study from Denmark also suggested a possible immune response based on prolonged fever in mothers during pregnancy. (9) Currently, no definitive environmental factors can predict diagnosis; therefore, the pediatric clinician's ability to screen children early for autism becomes extremely important.The AAP in 2007 recommended to pediatric clinicians that all 18- and 24-month-old children be screened for an ASD. Providing an early diagnosis of autism allows parents to access intensive behavioral treatments (ie, applied behavioral analysis [ABA]) that can ultimately improve a child's overall outcome in language, adaptive behaviors, academic performance, and IQ. Research has confirmed that the diagnosis of an ASD can reliably be made in the second year of life, but the overall predictive reliability and stability of a diagnosis at this age are lower. Children suspected of having an ASD through screening must be further evaluated as soon as possible. The AAP developed Caring for Children with Autism Spectrum Disorders: A Resource Toolkit for Clinicians or more simply the Autism Toolkit (www.aap.org) as a helpful guide for pediatric clinicians to screen, identify, and treat children with ASDs. The toolkit presents different practical items (clinician fact sheets and parent handouts) that help a primary care physician maintain a medical home for children with autism, discusses autism screening and identification, and provides the following 3 screening tools (also available separately online) used at different ages (Table 4):The Infant Toddler Checklist, also known as the Communication and Symbolic Behavior Scales and Developmental Profile, uses 24 total questions grouped into developmental milestones and social communication. There is also a final free-text question that asks, "Do you have any concerns about your child's development?" (http://firstwords.fsu.edu/pdf/checklist.pdf). The checklist has been studied as a broad-based screener for developmental problems and identified problems in 56 of 60 children ultimately diagnosed as having autism from a large population sample. (10) However, it could not easily distinguish between children with autism from children with other communication delays.The M-CHAT was developed from the previous British version called the CHAT. The M-CHAT uses 23 yes/no questions that expand on the previous CHAT. The difficult aspect of the M-CHAT is that it requires the practitioner to do an M-CHAT follow-up interview questionnaire orally (http://www2.gsu.edu/∼psydlr/Diana_L._Robins,_Ph.D..html) for screens with positive results, which can happen in 1 of 10 screens. This second-level screen for a positive M-CHAT result was studied by using follow-up telephone calls, which can eliminate 5 of 6 as not requiring referral. (11) This 2-step screening process has been combined and integrated into an online screening at www.m-chat.org. Unfortunately, the M-CHAT is unreliable in children older than 3 years. Therefore, a validated screening tool for autism at older than 3 years and especially in school-aged children is needed.Children who meet DSM criteria for ASD are often diagnosed by age 2 to 3 years. However, identifying subtler cases of ASD may take longer. Most subtle cases occur in children with minimal intellectual dysfunction and better language skills. Difficulties with functioning may not be noticeable until school-age, when social demands become greater. Recognizing older children with ASD can be challenging for the practicing clinician, educator, and parent. The use of the Childhood Autism Screening Test may prove helpful. This test provides yes/no questions with 1 point scored for each ASD-relevant response to questions related to social abilities and interest in being around other people. There are 37 total questions with a maximum score of 31. The cutoff for a positive screen is 15 or greater. This is only a screening test, but it can be helpful when responding to concerns by teachers and parents or, if the result is positive, to consider a second-level diagnostic test, such as the Autism Diagnostic Observation Schedule. Some children, who may have not been diagnosed as having ASD by the time they reach elementary school, may have been labeled with behavioral concerns or co-occurring problems, such as hyperactivity, inattention, aggressiveness, mood disturbances, or learning disorders. Alternatively, a child may have been diagnosed as having ASD when in fact another disorder may explain the reason for their symptoms. In addition, some children with an initial ASD diagnosis may no longer fit ASD criteria over time naturally or as a result of therapy. Sometimes the diagnostic process may not be straightforward, and consideration of a differential diagnosis, along with targeted diagnostic testing, may be indicated.All children being assessed should undergo a complete physical examination, specifically noting any neurologic abnormalities (macrocephaly and hypotonia) or oddities, such as toe-walking, dysmorphic features suggestive of any syndromes, and neurocutaneous skin findings consistent with neurofibromatosis or tuberous sclerosis, such as café au lait or ash leaf spots (Table 3). In addition, the practitioner should review the medical and family histories, focusing on developmental and behavioral issues. Children younger than 3 years with developmental delays should be immediately referred to an early intervention program whether or not the clinician is certain about a diagnosis of autism. If the child is older than 3 years, referral to the special education department at the local school should occur. Generally, the assessment teams for these services will have a speech-language pathologist, physical therapist, and an occupational therapist. Having multiple therapists and evaluations helps clarify the diagnosis and treatment planning.Children with communication problems and/or language delay should undergo audiology testing. This can be difficult and may ultimately require a sedated auditory brainstem response or a brainstem auditory evoked response test. Deciding on laboratory or diagnostic testing will be guided by a physical examination and medical history. For children diagnosed as having autism, testing for lead exposure, fragile X syndrome, and a comparative genomic hybridization array should be standard; moreover, the use of neuroimaging, electroencephalography, or metabolic testing should be reserved if indicated from physical examination or historical findings.Diagnostic dilemmas can occur when certain disorders are paired together and can simulate a diagnosis of autism, such as having a language disorder with ADHD or having an intellectual disability and visual impairment. In addition, when considering the differential diagnosis of a child with significant developmental delays, it is important to remember that harsh psychosocial conditions can elicit a response that may briefly mimic autism and other developmental delays. These disorders can include posttraumatic stress disorder, reactive attachment disorder, and child abuse. Generally, these disorders can be diagnosed over time after repeated evaluations, counseling, and therapy. This may require several months, and a diagnosis of autism may be withheld until the child's environment is evaluated for safety and stability. Mandated reporting of child abuse or neglect should be immediate when suspected, and follow-up communication with authorities is important.After confirming the diagnosis of autism, it is important to help the family identify a treatment strategy to provide the most effective therapy for their child. Intensive psychological and educational interventions are currently the primary treatments for addressing the core deficits in children with autism.The assessment and diagnostic process is often stressful for the family and the child; treatment and clinical care can be stressful too. Engagement of parents after the diagnostic process should be geared toward providing education, obtaining resources, and accessing supports. Autism Speaks is one of the largest advocacy and science organizations dedicated to the needs of individuals and families struggling with autism. They provide 2 useful parent toolkits: one that addresses children with lower functioning autism (http://www.autismspeaks.org/docs/family_services_docs/100_day_kit.pdf) and another for children with minimal intellectual disability and higher functioning (http://www.autismspeaks.org/docs/family_services_docs/AS-HFA_Tool_Kit.pdf).As mentioned earlier, the AAP provides helpful handouts from the Autism Toolkit, including the educational booklet Understanding Autism Spectrum Disorders, which helps parents navigate the consequences of an initial diagnosis of autism.Another helpful learning tool for residents and practitioners is Autism Case Training: A Developmental-Behavioral Pediatrics Curriculum (http://www.cdc.gov/ncbddd/actearly/act/class.html).Because of the rapid increase in the prevalence rate of ASD, many treatment services are not readily available, and treatment burden falls on clinicians. Families often look initially to the pediatric clinician for guidance to make treatment and educational decisions. Children with an ASD have high service use rates because of the complexity and early onset of the disorder, lifelong prevalence, and associated impairments. Many children also have co-occurring disruptive behaviors (eg, aggression, tantrums, and self-injury), which are common reasons for referral to medical and mental health services.There are several established behavioral and educational therapies and treatments available to treat the core symptoms of autism. Previously known as behavior modification, ABA is a behavioral treatment approach designed to increase socially appropriate behavior and decrease the severity and/or emergence of challenging behaviors. Widely recognized as an effective treatment for autism, ABA has been endorsed by a number of state and federal agencies, including the US Surgeon General. (12) ABA focuses on identifying the function of problem behavior and building skills to improve such behaviors. To facilitate appropriate behavior, ABA focuses on teaching specific behaviors in a systematic manner in the context of repeated trials. The therapy is tailored to meet the needs of the individual and requires support of the family.Research has demonstrated that ABA results in improvements in communication, social relatedness, and decreasing repetitive behaviors; however, these skills require additional training to generalize to environments and situations. ABA is extremely labor intensive and expensive and may be needed for several years.As ABA has evolved, several treatment approaches have been developed that use the ABA framework to improve behaviors associated with autism. In addition, many children with ASD require additional therapy to address issues such as speech and language delays and sensory problems (Table 5).Up to half of children with an ASD have an intellectual disability as measured by standard testing. However, many of these children may have strengths in visual spatial skills that are difficult to test. Many children with autism are first recognized by their language delay. In addition, impaired pragmatic and semantic language skills create learning difficulties for children with ASD. Children with an ASD are either in special education classrooms or the regular classroom with an individual education plan or 504 plan.Children with autism may have common medical problems, such as sleep disorders, constipation, and irritability, that a clinician may feel comfortable treating. However, addressing the common comorbid mental health issues, such as anxiety, ADHD, and disruptive behaviors, may be more challenging. Because of the complexity of ASD, it is important to take into account all possible diagnoses to be able to address the needs of the child and family. As the child gets older, these co-occurring mental health disorders could become the problematic aspect or the defining diagnosis in some cases. A helpful website to review and download tests for co-occurring diagnoses can be found at http://www2.massgeneral.org/schoolpsychiatry/screeningtools_table.asp. However, these screening tools are not specific to screening children with ASD.Anxieties and phobias can be found in up to half of all children diagnosed as having an ASD. Many children may have more than one phobia and/or anxiety related to objects or situations. Screening with the Spence Children's Anxiety Scale can help discern whether a child has separation and generalized anxiety, along with social phobia and panic disorders (http://www.scaswebsite.com/). The Self-report for Childhood Anxiety Related Disorders screens for 5 factors: general anxiety, separation anxiety, social phobia, school phobia, and physical symptoms of anxiety (http://psychiatry.pitt.edu/research/tools-research/assessment-instruments). Medication is rarely required in clinical practice unless the anxiety is debilitating. However, being able to recognize a mild anxiety disorder is helpful for parents when explaining how to modify these maladaptive behaviors.Obsessive-compulsive disorder is considered the second most common co-occurring condition with ASD and many times defines some early behaviors in children based on their unwillingness to change routines. More than one-third of children with an ASD continue with some type of obsession or compulsion that will limit their ability to interact socially. These behaviors are fairly easy to ask parents about and may not require any specific screening. Treatments with low doses of selective serotonin reuptake inhibitors have been administered in small trials with mixed success. Interestingly, a recent Cochrane review of selective serotonin reuptake inhibitor use in children with autism found no evidence of effect for either anxiety or obsessive-compulsive disorder. (13)ADHD is another common co-occurring condition in children with ASD. Use of the inclusive definition of all types of ADHD (inattentive, hyperactive, and combined) can encompass approximately two-third of all children with ASD. Children may be diagnosed as having and treated for ADHD with stimulants such as methylphenidates and amphetamines before a diagnosis of ASD is ever made. Some studies have suggested that ADHD may actually be considered somewhere along the continuum of the autism spectrum. (14) Screening and follow-up for ADHD can be accomplished with the Vanderbilt forms (http://www.pampapediatrics.com/client_images/File/vanderbilt-forms.pdf). The important caveat for children with autism who have ADHD is that they may be more sensitive to the medications and can have adverse effects and irritability at lower doses than children without ASD. Therefore, the mantra is to "start low and go slow" with medications. A therapeutic model for assessment and treatment of ADHD in a child with autism is provided (Figure). (15)Generally, depression can be seen in children with ASD as they get older and perhaps become more aware of their diagnosis. In middle school the pressure to conform is strong, and there is a low tolerance for being different. Children with ASD are likely to get teased and taunted or bullied and find it difficult to fit in. This may increase their social withdrawal and cause sadness, crying spells, and depression that may require medical treatment and counseling. The Pediatric Symptom Checklist is sometimes useful as a global screen when there may be more than one co-occurring disorder. The Pediatric Symptom Checklist has a short form (Pediatric Symptom Checklist 17) or longer form ( Pediatric Symptom Checklist 35) (http://www.brightfutures.org/mentalhealth/pdf/professionals/ped_sympton_chklst.pdf).Disruptive behavior may escalate to aggression, causing suspension from school and injury to siblings or parent. Behavioral therapy that targets these emotional outbursts can sometimes suffice, but many times the decision to start use of antipsychotic medications, such as risperidone or aripiprazole, may be necessary. It is important to perform a comprehensive evaluation to identify and assess target behaviors before launching into pharmacologic management. A comprehensive table, provided in the article by Myers et al, (16) that reviews the clinical approach before initiating pharmacologic management should be reviewed (Table 6).Occasionally, children with ASD may cycle rapidly through periods of depression and a decreased need for sleep with maniclike activity. If concerned about a bipolar diagnosis, it is best to refer to a psychiatrist for assessment and support. Anticonvulsant mood stabilizers, such as carbamazepine or valproic acid, or an atypical antipsychotic agent, such as risperidone or aripiprazole, are sometimes used.Use of psychotropic medications as a treatment of acute symptoms of irritability or disruptive behaviors tends to occur as children get older and if the children have increased intellectual disability when placed in a more restrictive educational environment. It is therefore important to use combined therapies of parent training programs with medication in treating children with ASD and challenging behaviors. (17)There is a high use of CAM among children with ASD. Parents often use CAM therapies along with conventional treatments for their child with autism, a combination of treatments often referred to as integrative medicine. (18) Parents appear to be more likely to use CAM therapies if their child has a coexisting gastrointestinal issue, seizure, or behavioral disorder. It is important to be familiar with and provide an open and nonjudgmental approach when discussing CAM therapies with parents. Unfortunately, some CAM therapies receive media attention (eg, secretin and hyperbaric oxygen) and become fads that are used by parents that may or may not have disposable income. Regrettably, many of these therapies have not been rigorously studied, and vulnerable parents develop false hopes that each new treatment may provide a cure for their child with autism.The following guidel
Referência(s)