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Autism in children

Autism in children

Key learning points

  • Autism is a lifelong neurodevelopmental disorder affecting social communication and includes rigid and repetitive behaviours
  • It is associated with high levels of family anxiety and stress
  • Autism affects 1.1% of the population

Autism spectrum disorder is a complex lifelong neurodevelopmental disorder that affects 1.1% of the population.1 It is a social communication disorder that is characterised by rigid and repetitive routines or behaviours. It is also commonly associated with difficulties in cognition, behavioural flexibility, sensory processing, emotional regulation and altered sensory sensitivity. 

History and classification

Autism did not appear in the International Classification of Diseases (ICD 9) until 1977. It was described as a triad of impairments with variable language development and intelligence quotient:

  • Social interaction.
  • Communication and imagination.
  • Repetitive stereotype pattern of activity.

As the concept of a spectrum developed, the number of subgroups increased to include autism, Asperger’s syndrome, atypical autism and pervasive developmental disorder (PDS-nos). Because these diagnoses were not applied consistently across different clinical settings, the Diagnostic and Statistical Manual of Mental Disorders (DSM 5) has brought all the groups together under the blanket diagnosis of autism spectrum disorder (ASD). DSM 5 has also described a dyad of impairments with the two components being: 

  • Impairment in reciprocal social communication.
  • Rigid and repetitive behaviours.

The next iteration of ICD 11 is expected in 2018 and it is likely to follow the same path with a blanket diagnosis of autism spectrum disorder.

Autism was initially believed to affect predominantly males, with a nine-to-one male-to-female ratio. The figure is now four to one.1 This is thought not to be due to females being less likely to have ASD, but rather a result of them being better at hiding their difficulties and fitting in with society’s expectations. There is an excellent training video produced by Cardiff University, which demonstrates the different way boys and girls present with autism.2

Clinical features in children

Autism is a spectrum condition, which means that children and young people with autism will have very different challenges and abilities. In recent years, autism has been much more visible in the media, with a multitude of news articles and even a Sesame Street character. Many more people are aware of the diagnosis of autism and parental concern has to be one of the key features that will bring the child to the attention of the health visitor.

Parental concerns should be addressed by taking a very detailed history. Children with ASD are more likely to have siblings with ASD. This suggests that there is a genetic basis, but many hundreds of genes have been identified in many different combinations that may contribute to the clinical picture.3 There is also a strong association with other neurodevelopmental disorders such as:

  • Learning difficulties.
  • Epilepsy.
  • Down’s syndrome.
  • Tuberous sclerosis.
  • Cerebral palsy.
  • Tourette’s syndrome.
  • Fragile X syndrome.
  • Attention deficit hyperactivity disorder (ADHD).

There are several in-utero factors that increase the risk of autism such as prematurity, sodium valproate use by the mother and parental schizophrenia or affective disorder. There has been growing evidence about the possible role of antidepressants in pregnancy, but this is confounded by the fact that depression itself appears to increase the risk.

To satisfy the diagnostic criteria for ASD, the clinical signs must have been present from an early age, although they may be too subtle to establish a diagnosis with certainty. Early signs include: 

  • Impaired or delayed language development, sometimes repeating back what has been said (called echolalia) or not babbling. 
  • There may be impaired responses to others or impaired interactions with others. At toddler group they will ignore all that is going on around them and pursue a limited activity. 
  • It is a mistake to believe that there is no eye contact – many children on the autism spectrum will make eye contact, but it may be impaired or sometimes absent. 
  • Toddlers may also fail to point at an object to satisfy their need, and fail to draw attention to something that is happening nearby. They may fail to wave goodbye until much older than expected. 
  • They have reduced imaginative play – failing to engage in mock tea parties or lining cars up rather than actually moving them along the ground.  
  • Many of their activities will be very repetitive, doing the same thing over and over again, and becoming distressed if an adult tries to draw them away from it. 
  • They are resistant to change and have particular problems at transitions – so starting pre-school may cause the signs of autism to become much more apparent. 
  • Many parents also report significant and very demoralising problems with sleep, the child may spend several hours awake each night or fail to settle in the evening. 
  • Another battleground can be mealtimes with restricted and rigid food preferences – such as only eating food of a specific colour, or not allowing different foods to touch on the plate. 
  • Behaviour can be quite challenging when their expectations are not met. This can be self-injurious, for example head banging, or may include damage to others and property. 
  • ‘Stimming’ is the term that has been adopted to describe motor mannerisms or repetitive actions that are used to calm anxiety or stimulate the child. This may include rapid hand movements, finger flapping, twirling rapidly on the spot (without getting dizzy) or rocking.
  • Hypo- and hypersensitivity to environmental things like noise, lighting, smells or touch are also common. The child may refuse to wear clothes with labels or may reject close contact when distressed.
Red flags
  •  Parental concerns
  •  Language delay/impairment
  •  Impaired response to others
  •  Impaired interactions
  •  Impaired eye contact and pointing
  •  Reduced imagination
  •  Restricted and rigid interests
  •  Problems with transitions or change

Routine screening for autism has not been recommended by the National Institute for Health and Care Excellence (NICE) in its clinical guideline.4  However, there are useful tools available for download, such as MChat ( modified checklist for autism in toddlers for those aged 16-30 months)5 or AQ10 – child (autism quotient 10-question checklist for children).6  

Communication and interaction

Autism is a communication disorder and you may need to adjust the way you gain information from a child. If the child is verbal it is important to ask direct and closed questions, avoiding too many choices or too much information at one time. Language needs to be as literal as possible as jokes or metaphors will not be understood. Lack of eye contact does not necessarily mean the child is not listening – start a question with their name, so they know you are speaking to them. Avoid touching a child without prior warning and allow more time than normal for a consultation.

Advocacy and supporting families

A specialist paediatrician makes the diagnosis of autism and referral will be necessary. There should be a local pathway for diagnosis and community staff will need to support the family as there is often a prolonged wait for assessment and diagnosis. Sadly, many facilities such as specialist schooling are dependent on the diagnosis being confirmed. This is a stressful time for families. Lack of sleep and challenging behaviour, coupled with a society that can be very judgmental, are distressing. There is also often parental guilt that it must be ‘their fault’ and sometimes a frantic search for a cure. 

A 1998 paper claimed an association with the measles, mumps and rubella vaccination (MMR). The link was subsequently disproved,7 but the drop in immunisation led to an increase in serious infections. Families need a lot of support while they learn about their child. They also need protecting from the multiple ‘cures’ that can be found on a Google search. There are no biochemical interventions known to treat the core features of autism.8 

There is growing evidence to support the use of psychosocial interventions and parent/carer training. Health visitors can encourage parents to make use of these programmes and resources such as The National Autistic Society (NAS).8 The autism strategy and statutory guidance calls for health and social care staff to have autism awareness training. More information on all these can be found in the Royal College of General Practitioners autism toolkit.9


1 Baird G, Simonoff E, Pickles A et al.  Prevalence of disorders of the autism spectrum in a population cohort of children in South Thames: the Special Needs and Autism Project (SNAP). Lancet 2006;368:210-5

2 Film to raise awareness of ASD. Available at:

3 Geschwind DH. Autism: many genes,common pathways? Cell 2008;135:391-5

4 NICE Clinical Guidance 128. September 2011. Autism: Recognition, referral and diagnosis of children and young people on the autism spectrum

5 Modified checklist for autism in toddlers. Available at:

6 Autism spectrum quotient. Available at:

7 Deer D. How the case against the MMR vaccine was fixed. BMJ 2011;342:bmj.c5347 S

8 NICE Clinical Guidance 170. August 2013. Autism: The management and support of children and young people on the autism spectrum

9 RCGP. Autism spectrum disorder. Available at:


The National Autistic Society website:

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Autism spectrum disorder is a complex lifelong neurodevelopmental disorder that affects 1.1% of the population.