What Is The Difference Between Rett Syndrome & Autism? 

What Is The Difference Between Rett Syndrome & Autism? 

More often than not, traits of Rett syndrome are misdiagnosed as autism. This is because the two conditions share very similar characteristics. In this article, Therapy Stars have made it their mission to clarify this misconception and highlight how they are different. So, let’s get straight into it! What is the difference between Rett syndrome and autism? 

The main differences between Rett syndrome and autism are: 

  • Rett syndrome occurs almost exclusively in girls (although in very rare cases can present in boys), while autism is much more commonly diagnosed in boys.
  • Many symptoms of Rett syndrome do not appear in autism spectrum disorder. These include things like slowed rate of head growth, loss of hand skills, less mobility, and irregular breathing. 
  • Whilst atypical social behaviour is a defining characteristic of autism, it is often only a temporary stage of Rett syndrome. 

Keep reading to learn more about the connection between Rett syndrome and autism in more detail. 

How Are Rett Syndrome and Autism Related?

In the Diagnostic and Statistical Manual of Mental Disorders (published in 1919), Rett syndrome was directly classified as one of the autism spectrum disorders (ASD). However, in the DSM-5 which came out in May 2013, Rett syndrome is no longer classified as an ASD. Using this edition, specific syndromes such as Rett syndrome that have some autistic features are no longer bundled under the new umbrella diagnosis of autism spectrum disorder. Instead, Rett syndrome is classified by its unique diagnosis code. 

While Rett syndrome is not classed as an official autism spectrum disorder in the DSM-5, the link to autism remains. In fact, many children are actually diagnosed as autistic before the MECP2 mutation is identified and then the diagnosis is revisited to Rett syndrome. 

Autistic traits are common during the regression period of Rett syndrome and sometimes, these traits persist. This is why Rett syndrome is often misdiagnosed. Using the new DSM-5, it is expected that many children will carry dual diagnoses of Rett syndrome and autism spectrum disorder. Let’s take a closer look at the similarities and differences between the two conditions:

Similarities Between Autism & Rett Syndrome 

Like autism spectrum disorder, Rett syndrome is not apparent at birth. In both conditions, a period of apparently typical development precedes the onset of early signs. These signs are similar for both children with Rett syndrome and autism and include:

  • Withdrawal from social interaction and communication issues 
  • Regression – The loss of previously acquired skills is prevalent in both Rett syndrome and autism. This regression happens around the same time in both conditions and involves similar trends, loss of language and social skills. 
  • Repetitive behaviours – In Rett syndrome, repetitive hand movements are often so frequent they prevent the children from using their hands in a purposeful way. Similar repetitive behaviours such as spinning, body-rocking and teeth grinding are also very common in children with autism. 
  • Anxiety and seizures 

Differences Between Autism & Rett Syndrome 

Whilst both conditions make it hard for children to communicate and socialise, there are some key differences between Rett syndrome and autism. The biggest difference between the two conditions is that Rett syndrome usually happens in girls, while autism is more commonly diagnosed in boys. This is because Rett syndrome is caused by a mutation of the X chromosome. Since males carry just one X and one Y chromosome, this phenomenon only occurs in females. 

Whilst atypical social behaviour is a defining characteristic of autism, it is often only a temporary stage of Rett syndrome. In fact, many girls with Rett syndrome become socially engaged again. While children with autism tend to avoid eye contact, those with Rett syndrome often learn eye movements to communicate their needs. 

Movement problems also tend to be much more severe for children with Rett syndrome compared to children with autism. While autistic individuals struggle with poor coordination, many girls with Rett syndrome are unable to walk. Rett syndrome also involves problems with the autonomic nervous system that can lead to fatal breathing abnormalities, a problem not seen in autistic children. 

What Can Studies of Rett Syndrome Tell Us About Autism? 

Scientists are busy investigating how regression unfolds in Rett syndrome in hopes of better understanding regression in autism. One issue that has arisen is that Rett mouse models do not show the loss of motor coordination and communication skills seen in people with the syndrome. 

As a result, some researchers are manipulating MECP2 in specific cells of the mouse brain to pinpoint the source of Rett syndrome traits. Deleting the inhibitory neurons only dampens brain signalling and can produce some of the syndrome’s traits (social deficits and motor problems). Consequently, experts have discovered that the signalling molecule, gamma-aminobutyric acid, is likely very important in Rett syndrome, just as it is in autism. 

To read more about autism, take a look at our insightful article surrounding W-Sitting and Autism

What Are The Symptoms of Rett Syndrome? 

The age when symptoms appear will vary from child to child however, most babies with Rett syndrome seem to grow normally for the first 6 months before any signs of the disorder become obvious. 

Some symptoms of Rett syndrome include:

  • Slowed growth – The brain does not grow properly and the head is usually smaller (doctors call this microcephaly). 
  • Problems with hand movements – Most children with Rett syndrome lose the use of their hands. 
  • Language issues – Between the ages of 1 to 4, social and language skills start to decline. Children with Rett syndrome often stop talking and experience extreme social anxiety. 
  • Muscle and coordination problems – This can make walking difficult. 
  • Breathing issues – This can include very fast breathing (hyperventilation), forceful exhalation of air or saliva and swallowing air. 
  • Seizures – Most children with Rett syndrome have seizures at some point during their lives. 
  • Behaviour changes – Children with Rett syndrome tend to become tense and irritable as they get older. Some children with this condition also make unusual faces, lick their hands or grasp at hair or clothes. 
  • Unusual eye motion – This can include staring or blinking intensely, crossed eyes or shutting one eye at a time. 
  • Sleeping issues – Your child might have a hard time falling asleep at night and nodding off during the day. 
  • Scoliosis – This sideways curve in the spine is common with Rett syndrome. Generally, it begins when a child is between the ages of 8 and 11 years old and gets worse with age. 
  • Irregular heartbeat – Many children and adults with Rett syndrome have this serious condition, which can prove life-threatening without treatment. 

To read more about our intensive physiotherapy, take a look at our article, ‘What Is Intensive Physiotherapy & Which Conditions Can It Treat?’

What Are The Stages of Rett Syndrome? 

Rett syndrome is described in 4 stages, although symptoms will often overlap between each stage. These are the four main features of each stage: 

Stage 1 – Early Signs 

Initially, the child will appear to develop and grow normally for at least 6 months. There may only be subtle signs of Rett syndrome before the child is recognised as having a problem. Often referred to as ‘stagnation’, early symptoms include:

  • Low muscle tone (Hypotonia – Refers to decreased muscle tone and too much flexibility) *To find out more about the opposite condition, Hypertonia (increased muscle tone and lack of flexibility) – take a look at our article, ‘Hypertonia: What Does It Mean & Is It Curable?’. 
  • Difficulty feeding
  • Unusual, repetitive hand movements or jerky limb movements 
  • Delay with development of speech 
  • Mobility problems (sitting, crawling and walking)
  • Lack of interest in toys 

Symptoms typically begin from 6 to 8 months however, it’s important to note that stage 1 can often go unnoticed because the changes occur gradually. 

Stage 2 – Regression 

During the ‘rapid destructive stage’, the child starts to lose some of their abilities. Generally, this stage begins between the ages of 1 and 4. The child will gradually start to develop severe problems with communication, language, memory and coordination. Many of these are similar to those of autism. 

Signs at this stage include:

  • Periods of distress and irritability 
  • Social withdrawal
  • Unsteadiness and awkwardness when walking 
  • Sleeping problems 
  • Slowing of head growth 
  • Loss of the ability to use hands purposefully 
  • Problems with heart or heart rhythm 

Stage 3 – Plateau 

Stage 3 of Rett syndrome can begin as early as 2 years or as late as 10 years. It can last for many years, with lots of children remaining in this stage for most of their lives. 

Symptoms at this stage include:

  • Seizures 
  • Irregular breathing patterns
  • Gaining and maintaining weight can also be difficult at this stage

Stage 4 – Deterioration in Movement 

Stage 4 can last for years or even decades. The main symptoms at this stage are:

  • Muscle weakness and spasticity 
  • Losing the ability to walk 
  • Development of a spinal curve 

To find out more about Rett syndrome, take a look at our article, ‘What Conditions Can Children’s Physiotherapy Treat?

Rett Syndrome Therapy at Therapy Stars 

It’s crucial to maintain a good range of motion in children with Rett syndrome to help prevent or delay the onset of physical contractures. At Therapy Stars, we aim to encourage a good range of motion for your child, helping to facilitate good development as they grow. We support children with Rett syndrome from birth up to young adulthood, with:

  • Minimising contractures by stretching the muscles to maintain elasticity 
  • Maintaining and improving bone density through regular standing 
  • Maintaining or improving range of motion 
  • Maintaining or improving balance 
  • Postural management 
  • Assessing for appropriate adaptive aids 

We also offer hydrotherapy and DMI therapy to help with motor skills, balance, body alignment and posture. 

If your child is presenting with symptoms or has been diagnosed with Rett syndrome, get in touch for a free initial consultation and physical assessment. We’re also happy to simply offer advice and answer any questions you may have. 

Rett Syndrome FAQs 

What Is Rett Syndrome?

Rett syndrome is a neurodevelopmental disorder which affects the development of the brain and nervous system, as well as other features of growth, such as height. This condition mostly affects females. Whilst this genetic condition is not life-threatening, it can severely limit the function of anyone with the condition. 

What Causes Rett Syndrome? 

Rett syndrome is a genetic disorder caused by a mutation of the X chromosome in the MECP2 gene. The symptoms and severity of Rett syndrome depend on the exact location and type of mutation. 

How Is Rett Syndrome Diagnosed?

Rett syndrome is diagnosed through the observation of clinical symptoms and growth patterns of affected children. On top of this, there is also a genetic test that can detect the mutation of the MECP2 gene however, a paediatric neurologist, clinical geneticist or development paediatrician should confirm the results. 

What Is The Treatment For Rett Syndrome? 

Unfortunately, there is no cure for Rett syndrome. Any treatments offered only attempt to help manage symptoms, not cure the condition. Examples of treatments that may be used include:

  • Medication to manage motor disorders, tremors or spasticity 
  • Anticonvulsant medications for seizure control
  • Heart monitoring 
  • Regular spinal and neurological checkups
  • Occupational therapy
  • Physiotherapy 
  • Mobility devices, such as braces or splints 
  • Nutritional therapy or feeding assistance 
  • Breathing treatments or assistive devices 
  • Academic and social support services 

When it comes to Rett syndrome, a multidisciplinary approach is usually needed; however, exact treatments will depend on the specific symptoms and severity. 

To find out more about how physiotherapy can help with genetic conditions, take a look at our article, ‘Why Would a Child Need Physiotherapy?’.