AUTISTICSPECTRUM DISORDERS

The term autistic spectrum disorder refers to a range of clinically similar disorders with variable severity, all characterized by a diad of: (a) impaired social communication and interaction, and (c) rigid, repetitive or obsessive behavior.

Earlier terms of childhood autism, infantile autism, Asperger's disorder, pervasive developmental disorders are now all included under the umbrella of autistic spectrum disorders.

Incidence: While reported incidence of autism in India is in ~1 in 65 children aged 2-9 years, under-diagnosis is common and incidence seems to be rising due to increasing awareness. Autism is 3-4 times more common in males and in high socioeconomic strata, perhaps due to better chances of detection.

Etiology is not well established though ASDs are frequently associated with: (a) family history,

(b) chromosomal disorders, e.g. fragile X chromosome,

(c) genetic disorders, e.g. phenylketonuria, (d) intra­uterine infections, e.g. rubella, (e) congenital brain malformations, e.g. hydrocephalus, and (f) postnatal encephalitis, meningitis and infantile spasms. Familial or genetic predisposition is supported by ~ 80% and 20% concordance rate in monozygotic and dizygotic twins.

Clinical features: Autistic children are often mistaken as “good babiesquot; in infancy, as due to poor social interaction, they do not demand much attention. Average age of diagnosis in Indian children is ~3-6 years, though reliable diagnosis can be made as early as 18-24 months of age. Infants who demonstrate echolalia or abnormal hand movements or spinning, etc. should be evaluated for Autism spectrum disorder. Delayed development of verbal and non-verbal communication is usually the initial parental concern in second year of life, with gradual recognition of typical features, as follows:

a. Impaired social interaction: These children do not show any interest in their parents and do not make friends.

b. Impaired communication with lack of both, verbal as well as non-verbal communication skills. Even after the development of speech, they are unable to sustain a conversation and have other abnormalities, e.g. echolalia, pronominal reversal, nonsense rhyming, etc.

c. Stereotype behaviors, i.e. inordinate desire for sameness with rigid interests and repetitive or obsessive acti­vities. These children tend to play for many hours with one object, alone, and do not want to be disturbed.

d. Associated behavioral problems, e.g. hyperactivity, short attention span, impulsivity, aggressiveness, temper tantrums are common. Most of them have odd responses to sensory stimuli, e.g. higher pain threshold or over-sensitivity to touch, sound, light, odors, etc.

Intelligence is almost always affected with average IQ of lt;70 in most cases and many cases have seizures or associated problems, e.g. abnormal gait, toe-walking, etc. Diagnosis of autism is essentially clinical, based on the DSM V criteria (Table 3.17). However, the assessment of its severity and presence of co-existing abnormalities require: (a) comprehensive assessment of hearing, speech and language, (b) periodic evaluation for cognitive functions (IQ testing), social adjustment, verbal and non-verbal communication, (c) evaluation for secondary behavioral disorders.

Indian Academy of Pediatrics (IAP) recommends that:

a. All children should be screened by a standardized autism screening tool at 18 and 24 months of age, e.g. Modified Checklist for Autism in Toddlers (M-CHAT- R^tm) (Table 3.18).

TABLE 3.17: Diagnostic criteria for autism (DSM V)*

A. Persistent deficit in social interaction (All four)

- Deficit in social-emotional reciprocity

#9830; Abnormal social approach,

#9830; Failure of normal back-and-forth conversation

#9830; Poor sharing of emotions/interests

#9830; Failure to initiate/respond to social interaction

- Deficit in normal verbal communication

#9830; Poor eye contact or body language

#9830; Deficit in understanding/use of gestures

- Deficit to develop/ maintain relationships

#9830; Difficulty in adjusting behavior with social context

#9830; Difficulty in sharing imaginative play

#9830; Difficulty in making friends

B.

- Stereotype, repetitive motor movements/ speech

- Insistence on same, rigid routine

- Restricted, fixed interests (attachment to objects)

- Hyper-/hypo- reactivity to sensory inputs, e.g. indiffer­ence to pain, visual fixation with lights

C. Symptoms since early childhood, though masked

D. Symptoms causing significant functional impairment

E. Not explained by intellectual disability or other causes ‘Modified for brevity.

Severity for criteria A and B must be described in 3 levels:

Level 3 - requires very substantial support,

Level 2 - requires substantial support, and

Level 1 - requires support.

b. If the screening test is positive, they should be referred for expert and comprehensive evaluation assessment and timely initiation of intervention. Indian Scale for Assessment of Autism (ISAA) or Childhood Autism Rating Scale (CARS) are commonly used tools to confirm the diagnosis.

c. Children lt;18 months should also be evaluated for social communication skills and must be followed up, till formal screening

M-CHAT-R^tm is a simple and freely available screening tool for ASD in toddlers between 16 and 30 months of age (Table 3.18). As a screening tool, M-CHAT-R^tm aims to maximize sensitivity and detect as many cases of ASD as possible and hence, has a high false-positive rate. A follow-up test (M-CHAT-R#8725;F^tm) is also available for borderline cases, though no child should be diagnosed as ASD on the basis of M-CHAT alone (which is only a screening test), but must be referred for further assessment.

D/D of autism includes other cause of inattentiveness and poor communication, e.g. deafness, intellectual disability, developmental language disorder, childhood schizophrenia and attention-deficit hyperactivity disorder.

Rett syndrome is a rare, X-linked disorder, almost exclusively seen in females (lethal in males), characterized by normal development till 6-12 months, followed by regression of motor and linguistic milestones, secondary microcephaly, and stereotyped hand movements, e.g.

Management of autistic children is a long process and aims to achieve as much functional independence as possible and requires a multi-disciplinary team approach involving pediatrician, developmental pediatrician, psychologist, occupational therapist, speech therapist, special educator, etc.

Intervention should begin as early as possible, even while confirmation of the diagnosis is in progress and should be specific, evidence-based, structured and appropriate to the developmental needs of the child.

Aims of the management have to be realistic and include:

a. Enhancing eye contact, social orientation, nonverbal and verbal communication,

b. Reducing repetitive/restricted behaviors, sensory issues and hyperactivity, and

c. Improving social, motor, and behavioral capabilities. Many good interventional models are in use for these children.

Important components of management include:

a. Pharmacotherapy, though not curative, is a valuable tool to control certain symptoms. Choice of drug depends on predominant symptoms and includes: (a) Methylphenidate to control hyperactivity (PO 10-40 mg/day in morning), (b) Atomoxetine (PO 1.2 mg/kg/day), if methylphenidate is not tolerated, (c) Risperidone to control aggressive and self-injurious behavior (PO 0.5-3.5 mg/day), (d) Fluoxetine to control repetitive and rigid behaviors (PO 2.4-20 mg/ day), and (e) Melatonin (PO 0.5-1. mg/day) before bed-time for insomnia. Other drugs may be required for co-morbidities, e.g. anxiety, mood disorders, etc.

b. Play therapy, language therapy and behavior therapy using operant conditioning, have shown promising results in some cases as also psychotherapy in children with at least some communication.

c. Educational management: While inclusive education is the ideal goal, it needs to be rationalized and based on individual situation. An appropriate individualized educational plan should reflect accurate assessment of the child's strengths and vulnerabilities and their relation to academic skills.

d. Family therapy is required for parents to understand the problem and cope with the stress of the illness. Currently, many support groups involving affected parents, health professionals and voluntary organi­zations are working in India for this purpose.

e. Disability support: Under the Disability Act 1999, ASD is recognized as a disability, after certification by a designated Autism Certification Medical Board.

Reproduced with permission:

For all items except 2, 5, and 12, the response quot;NOquot; indicates ASD risk; for items 2, 5, and 12, quot;YESquot; indicates ASD risk. Following algorithm maximizes psychometric properties of the M-CHAT-R:

• LOW-RISK (Total Score 0-2) No further action required unless surveillance indicates risk for ASD. However, rescreen after second birthday, if child is lt; 24 months old.

• MEDIUM-RISK (Total Score 3-7) Administer M-CHAT-R/F (Not included here). If the remains at 2 or higher, child has screened positive and refer for further evaluation. If score on follow-up is 0-1, child has screened negative and no further action required unless surveillance indicates risk for ASD. Child should be rescreened at future visits.

• HIGH-RISK: Total Score is 8-20; refer immediately for diagnostic evaluation and eligibility evaluation for early intervention.

Prognosis: Autistic children, reared in a positive environ­ment, show some improvement during early school years. However, symptoms tend to aggravate during adolescence with deterioration in behavioral and cognitive skills, additional psychiatric problems and appearance of epilepsy, especially in girls. As sexual drive increases, they may indulge in embarrassing behaviors.

Absence of communicative speech till 5-6 years of age indicates poor prognosis.

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