Autism Spectrum Disorder
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Direct answer
Autism spectrum disorder is a neurodevelopmental disorder defined by persistent deficits in social communication and interaction together with restricted, repetitive patterns of behaviour, interests or activities, present from the early developmental period and causing functional impairment. DSM-5 merged autistic disorder (Kanner's infantile autism), Asperger syndrome, childhood disintegrative disorder and pervasive developmental disorder not otherwise specified into a single spectrum with severity gradings for the two domains. There is no curative drug; structured behavioural and educational intervention begun early gives the best outcome, with medication used only for comorbid problems.
What you must remember
- Domain one — social communication: reduced social-emotional reciprocity, deficient non-verbal communication (poor eye contact, absent pointing, limited gestures) and failure to develop age-appropriate peer relationships.
- Domain two — restricted and repetitive behaviour: stereotyped movements, speech or object use (hand flapping, lining up toys, echolalia); insistence on sameness; abnormally intense restricted interests; and hyper- or hypo-reactivity to sensory input.
- Diagnostic rule: all three social-communication deficits plus at least two of four restricted-behaviour features, present from early development, causing impairment, and not better explained by intellectual disability — DSM-5 grades severity from level 1 to 3.
- Early red flags: no pointing or joint attention by about 12-18 months, not responding to name, and loss of babbling or words; roughly half of children with classical autism have intellectual disability, while Asperger-type presentations preserved intelligence and language.
- Differentials and epidemiology: childhood disintegrative disorder (regression after two normal years) is now within the spectrum, Rett syndrome was removed, and hearing impairment must be excluded; prevalence is roughly one in a hundred per World Health Organization figures, boys affected about four times more often.
- Management: early intensive behavioural programmes (applied behaviour analysis), speech therapy, social skills training, special education and parent training; risperidone and aripiprazole treat severe irritability and aggression — no drug treats core autism.
Common confusion
Autism versus intellectual disability: the child with intellectual disability alone relates warmly, uses gestures proportionate to mental age and shows flexible interests, whereas the autistic child shows aloofness or one-sided social approach with stereotypies. In specific language impairment the child compensates with gesture and shared enjoyment, while the autistic child does not point or show objects.
Exam-focused takeaway
NEET-PG describes a toddler who does not point, does not respond to his name, lines up cars, flaps his hands and screams at loud noises — autism is the answer, with echolalia and insistence on sameness as supporting clues. One-liners test the two DSM-5 domains, the Kanner and Asperger eponyms, four-to-one male predominance, sensory reactivity, and co-occurrence with tuberous sclerosis or fragile X syndrome. Management stems reward early behavioural intervention and risperidone or aripiprazole for irritability.
Frequently asked questions
What are the two core diagnostic domains of autism spectrum disorder?
Persistent deficits in social communication and interaction, and restricted, repetitive patterns of behaviour or interests — both present from early development and causing impairment.
What happened to Asperger syndrome in DSM-5?
It was merged into the single diagnosis of autism spectrum disorder, graded level 1 to 3 by severity in each domain.
What early red flags suggest autism in the second year?
No pointing or joint attention, not responding to name, absent pretend play and loss of acquired words.
How is autism different from intellectual disability?
Intellectual disability alone preserves warm, flexible social interaction, while autism shows aloof or one-sided social behaviour with stereotyped interests.
Which drugs have a role in autism?
None treat core features; risperidone and aripiprazole help severe irritability and aggression.
What is echolalia in autism?
Meaningless repetition of heard words or phrases, immediate or delayed, reflecting the pragmatic language deficit.