Autism Spectrum Disorder

Question 1

Define ASD.

Answer 1

Autism is a neurodevelopmental condition characterized by a triad of:

1. impairment in social interaction
2. speech and language disorder
3. imposition of routines with ritualistic and repetitive behaviour

Question 2

How common is ASD? What is the M:F ratio?

Answer 2

0.06% worldwide, 1.1% in UK

x4 more common in boys than girls

Question 3

Do all patients with ASD have intellectual impairment?

Answer 3

ASD may occur in association with any level of general intellectual/learning ability

Question 4

What is the aetiology of ASD?

Answer 4

• Multiple aetiology
• Heritability is 80-90% (so only ~10% is environmental)

NOT the result of emotional trauma/deviant parenting

NO link with MMR

Question 5

What pathology has been found by studies to be present in ASD?

Answer 5

• Abnormalities in major cortical and subcortical brain structures (on MRI/postmortem)
• Structural & functional impairment
• Some studies show increased cerebral volume.
• Abnormal cerebellar functioning - ?too many synapse connections
• Elevated blood 5HT levels

Question 6

What other conditions commonly coexist alongside ASD?

Answer 6

• Epilepsy (~ one third)
• Genetic conditions e.g. Fragile X
• ADHD (about two thirds)
• Affective disorders e.g. anxiety, sleep disturbance
• Intellectual impairment
• Sepcific learning difficulties
• Schizophrenia and related disorders
• GI disturances (may be related to pica)
• Higher head circumference to brain volume ratio.

Question 7

What genetic conditions are associated with ASD?

Answer 7

• Fragile X (21-50% have ASD)
• Tuberous sclerosis complex (24-60%)
• Di George syndrome (22q11 deletion syndrome) (25x risk of schizophrenia, 40% meet ADHD criteria, 33% have OCD, 30% meet ASD criteria)
• Mitochondrial disorders(~25%)
• Down Syndrome (0-17%)
• Prader-Willi Syndrome
• Angelman Syndrome

Question 8

What is used in the diagnosis of ASD?

Answer 8

ICD or DSM5

Clinically diagnosed by observation of behaviours, and using standardised tests, as early as 2 years old e.g.

1. Autism Diagnostic Observation Schedule-Generic (ADOS-G)
2. Autism Diagnostic Interview Revised (ADI-R) [recommended by NICE].
3. Diagnostic Interview for Social and Communication Disorders (DISCO)

Question 9

When is ASD most commonly diagnosed?

Answer 9

Presentation is between 2-4 years when language and skills normally rapidly expand.

Social communication impairments and repetitive behaviours are present during early childhood (typically evident before 2–3 years of age), but may be manifested later.

Question 10

Give 3 examples of impaired social interaction in ASD.

Answer 10

1. Playing alone and being uninterested in playing with other children
2. Does not seek comfort, share pleasure or form close friendships
3. Gaze avoidance
4. Socially and emotionally inappropriate behaviour
5. Does not appreciate others’ thoughts and feelings
6. Lack of eye contact, facial expression and gesture use
7. Does not appreciate social cues

Other:

• Total lack of awareness to difficulty making eye contact/gaze avoidance
• Children do not lift arms in anticipation of being help
• Lack of curiosity in surroundings
• Lack of empathy
• Socially isolated, one-sided social interaction
• Difficult to form friendships and maintain them

Question 11

Give 3 examples of speech and language disorder in ASD.

Answer 11

1. Echolalia, refers to self as ‘you’
2. Delayed development of speech and language
3. Limited use of gestures and facial expressions
4. Formal pedantic language, monotonous voice
5. Impaired comprehension with over-literal interpretation of speech

Other:

• Immediate or delayed echolalia
• Use literal idiosyncratic phrases or neologisms.
• Verbal autistic may speak in detailed and grammatically correct phrases, which are still repetitive, concrete, and pedantic.
• Impairment in pretend play. Some cannot grasp the concept of pretend play while others use restricted objects in a repetitive / mechanical fashion.

Question 12

Give 3 examples of repetitive behaviours, interests and activities seen in ASD.

Answer 12

Imposition of routines with ritualistic and repetitive behaviours:

1. Violent temper tantrums if disrupted
2. Stereotypes and repetitive motor mannerisms e.g. hand flapping, tiptoe gait, rubbing, rocking, clapping, odd posture
3. Concrete play
4. Lack of imaginitive play
5. Peculiar interests and repetitive adherence
6. Restriction in behaviour repertoire

Other:

• Very strong preferences and likes/dislikes
• Classic behaviour of lining up toys/collection
• Fascinations (cars, trains, dinosaurs etc) are unusually strong and they tend to know every little detail about the matter of interest. Keen to share knowledge
• Highly unusual preoccupation wuith special interests

Question 13

Comment on the other features of autism (including sensory sensitivity and impaired motor skills).

Answer 13

Sensory sensitivity - may be over or under sensitive to different stimuli like light, sound, taste and touch.

Impaired motor skills - gross or fine moto affected; may be clumsy/poorly coordinated/abnormal gait/problems with handwriting,

Question 14

What is the goal of management of ASD?

Answer 14

There is no cure but early diagnosis and intensive treatment can improve outcomes.

This includes:

• educational and behavioural management
• medical therapy
• family counselling

Goal is to increase independence and quality of life through:

• learning and development, improved social skills, improved communication
• decreased disability and comorbidity
• aid to families

Question 15

What is the bio-psycho-social model for management of ASD?

Answer 15

Question 16

Which other medical conditions should be excluded when diagnosing ASD? (Ddx)

Answer 16

• Fragile X syndrome - clinical microarray testing or whole exome sequencing
• Tuberous sclerosis - use Wood light to search for hypopigmented macules
• Chromosomal abnormality
• Hearing difficulties - audiology
• Rett syndrome - normal development followed by slowed head and brain growth, gait abnormalities and loss of purposeful use of hands, intellectual disability and seizures

Question 17

What are the non-pharmacological therapies available for ASD?

Answer 17

Applied behavioural analysis (ABA) to reduce ritualistic behaviour, develop language, social skills and play, and to generalise use of all these skils BUT requires 25-30 hours of individual therapy per week, is costly and time consuming.

Input from early educational services

MDT therapies e.g.

• SALT - reinforcing sound repetition and word use
• Occupational therapy - sensory-based interventions to address sensitivity to sounds, repetitive or challenging behaviours
• Physiotherapy - helps if low muscle tone present or co-ordination disorder

Others:

• Early Start Denver Model (ESDM)
• Joint Attention Symbolic Play Engagement and Regulation (JASPER) - used in US and Canada.
• Teaching and Education of Autistic and Communication handicapped CHildren (TEACCH)/Structured teaching method

Question 18

What are the pharmacological interventions available for ASD?

Answer 18

• SSRIs - reduce symptoms like repetitive stereotyped behaviour, anxiety, and aggression
• Antipsychotic drugs (e.g. Aripirazole and Rosperidone) - reduce aggression, self-injury
• Methylphenidate/stimulants- for ADHD
• Dopamine blockers help stereotypical behaviour
• Pregabalin

Experimentally:

• Opiate antagonists (naltrexone)- hypothesis: brain secretes beta-endorphins and blocking that may benefot CF like social isolation, stereotypical behaviours etc

Question 19

What does family support and counselling for ASD involve?

Answer 19

Parental education on interaction with the child and acceptance of his/her behaviour by professionals - the core training is done by the parents as opportunities arise at home or during play.

Family members benefit from forums where they can learn more.

Question 20

What is Asperger syndrome?

Answer 20

Term not used by the DSM5- refers to child with social impairments of an ASD at the milder end, with near normal speech development. They still have major difficulties with social cues, intense interests not shared with others and are often clumsy.

Question 21

What is the prognosis with ASD?

Answer 21

<10% of children with autism are able to function independly as adults

Question 22

What are the sex differences in ASD?

Answer 22

Females:

• have more desire for social contact and peer group acceptance
• may be more able to mask social play deficits by imitating peers
• interests may be in more socially typical domains
• have better coping skills leading to fewer and later diagnoses
• may show more subtle signs of repetitive/restrictive behaviour
• show less impairment in theory of mind tasks
• may be more likely to present with eating disorders
• present as shy, perfectionistic, or ‘bossy’ trait

Question 23

What are the causes of microcephaly?

Answer 23

Microcephaly = head circumference <2nd centile

• normal variation e.g. small child with small head
• familial e.g. parents with small head
• congenital infection
• perinatal brain injury e.g. hypoxic ischaemic encephalopathy
• fetal alcohol syndrome
• syndromes: Patau
• craniosynostosis

Question 24

What is echolalia? When does it become pathological?

Answer 24

Immediate non-communicative repetition of words or phrases – simply repeating exactly what was heard without synthesizing the intrinsic language.

It’s a crucial aspect of language development in infants <2yrs old but becomes pathologic when still present as sole and predominant expressive language after the age of ~ 18– 24 months

Question 25

What is delayed echolalia?

Answer 25

Delayed echolalia or scripts = use of highly ritualized phrases that have been memorized, such as from TV or overheard conversations

Question 26

What is the difference between Asperger’s and ASD?

Answer 26

Now part of ASD in the DSM-5

Same features of ASD (impairment in non verbal communication, and restricted/stereotyped patterns of behaviour/interests/ activities) but with normal language and cognitive development.

Pathophysiology is likely to be similar

Question 27

Behaviour chart used in ASD on the wards

Answer 27

ABC 4 factor checklist - this is a checklist used to analyse behaviour improvement on the ward