Autistic Spectrum Disorder

Question 1

When was the last revision from DSM-5 for ASD diagnosis?

Answer 1

2013

Question 2

When was the last revision from ICD for ASD?

Answer 2

ICD-11 in 2018

Question 3

What is social/pragmatic communication disorder?

Answer 3

A new diagnostic category introduced in DSM-5 to identify those individuals with persistent deficits in social communication and social interaction in the absence of restricted, repetitive patterns of behaviour, interests and activities

Question 4

What is ASD?

Answer 4

Autism spectrum disorder has been characterized by qualitative behavioural abnormalities in communication, reciprocal social interaction together with patterns of repetitive, restricted and stereotyped interests and activities. These deficits are pervasive, persistent, usually present in early childhood and likely to lead to impairments in functioning across different settings.

Question 5

How common is ASD?

Answer 5

The National Institute of Health and Clinical Excellence (NICE) states the diagnosis is queried in approximately 3% of the child population and epidemiological studies suggest prevalence rates of at least 1 in 100.

Question 6

What is the genetics behind ASD?

Answer 6

It has a complex genetic basis with strong heritability (60% concordance reported in twin studies). Recurrence rates for siblings have been reported between 3 and 10% with up to 18.7% when the broader autism spectrum is considered.

Question 7

How often is ASD associated with a different medical condition?

Answer 7

In 10–15% of cases ASD is associated with a known medical condition. Consistently recognized genetic conditions include tuberous sclerosis (TS) and fragile X.

Question 8

What the risk factors for ASD?

Answer 8

• Sibling with ASD

•

Parental schizophrenia-like-psychosis or affective disorder

•

Maternal sodium valproate use during pregnancy

•

Gestational age less than 35 weeks

•

Intellectual disability

•

Birth defects associated with central nervous system including cerebral palsy

•

Down syndrome

•

Fragile X

•

Tuberous sclerosis

Question 9

What are the associated medical condtions?

Answer 9

Neurofibromatosis

Phenylketonuria (untreated)

Fetal alcohol syndrome

Smith–Lemli–Opitz syndrome

CHARGE syndrome

Duchenne muscular dystrophy

Congenital rubella

Iron-deficiency anaemia

Question 10

How often is macrocephaly seen in ASD?

Answer 10

20-30%

Question 11

What is the significance of macrocephaly in ASD?

Answer 11

Macrocephaly is a recognized feature of ASD in 20–30% of cases though must be interpreted in the context of parental head circumferences. Studies have shown that as a group, head circumference accelerates during the first 2 years of life, with deceleration possibly occurring in later childhood since average head circumference has been reported in adolescence and adulthood. Although there have been conflicting views around the relevance and cause of these changes, they are reported to happen prior to the onset of clinical symptoms and may be a useful clinical indicator. Gene mutations in PTEN (Phosphatase and Tensin Homolog) have been found in children with ASD and macrocephaly with case series reporting a yield of 5% in those with head circumferences greater than 98th percentile.

Question 12

Why is there a delay in ASD diagnosis until 4-5 years of age?

Answer 12

Due to a combination of factors that include

• variability of assessment pathways
• demand on services
• lack of recognition of subtle difficulties at a young age
• presence of additional diagnoses and inclusion of school age individuals who may only present at an older age when their difficulties may become more overt as they are unable to manage increasingly challenging academic and/or social expectations.

Question 13

What the earliest feature of ASD?

Answer 13

Difficulties and delay in social interaction are often the earliest features in ASDs

Question 14

Which feature is highly suggestive of ASD?

Answer 14

Lack of joint attention

Question 15

What is absence of joint attention?

Answer 15

failure to show interest, share a focus of attention and follow gaze

Question 16

What are examples of gestures that may be inadequate?

Answer 16

shaking head, nodding, waving, clapping

Question 17

What is the difference between specific language disorder and ASD?

Answer 17

In contrast to those with specific language disorders, children with ASD often fail to use gestures or mime to compensate. Instead, parents may describe the child either obtaining a required object themselves or taking another person’s hand to the object as if to use them as a ‘tool’.

Question 18

How is language affected?

Answer 18

Language is often atypical with idiosyncratic use of words or phrases, e.g. nonsense or jargon words, or referral to self as ‘you’ (pronominal reversal). Other features include abnormal delivery of speech (prosody), i.e. unusual pitch, speed, volume or tone. Whatever the language skills present, two-way reciprocal conversational interchanges tend to be difficult, particularly if the topic of conversation is restricted to the narrowed/circumscribed and repetitive interest of the affected individual. An individual with ASD often struggles to engage in social chat and build on conversation about someone else’s hobby or interest.

Question 19

What is delayed echolalia?

Answer 19

Delayed echolalia is the term applied to copied or directly imitated speech, e.g. from an adult (such as a relative or teacher, television or radio) that is repeated some time after it is originally heard.

Question 20

How often is regression seen in ASD?

Answer 20

20-30%

Question 21

When is language regression most often reported?

Answer 21

Regression most commonly affects language, usually at the less than 10 word stage, therefore it is most often reported from 18 to 24 months of age.

Question 22

What to worry about if there is regression after 3 years?

Answer 22

Autistic regression in children over 3 years or regression in motor domains warrant careful assessment by a paediatrician or paediatric neurologist to consider neurodegenerative conditions, such as Rett syndrome and Landau Kleffner.

Question 23

How ofetn is LD seen in ASD?

Answer 23

Comorbid learning disability is reported to affect approximately 50% of people with ASD’s

Question 24

What is the association between ASD and epilepsy?

Answer 24

The risk of epilepsy in ASD is increased compared with the general population and linked to lower IQ and regression, with peaks of incidence occurring at pre-school age and adolescence. Between 18% and 29% of children with ASD are affected and any seizure type can occur.

Question 25

How often is EEG abnormal in ASD patients?

Answer 25

Epileptiform EEGs are common in ASD, and studies have shown that 10% of children with ASD have an epileptiform EEG without any clinical evidence of seizures.

Question 26

Which group of ASD patients are at risk of epilepsy?

Answer 26

The risk of epilepsy in ASD is increased compared with the general population and linked to lower IQ and regression, with peaks of incidence occurring at pre-school age and adolescence.

Question 27

When to refer for ASD assessment?

Answer 27

• absence of babble, gesture or pointing by 12 months
• no single words by 18 months
• no two-word spontaneous phrase (non-echoed) by 24 months
• any loss of language or social skills at any age.