Rett Syndrome

Date First Published: April 2, 2007
Date Updated: November 22, 2010

Rett syndrome is listed in the Diagnostic and Statistical Manual - IV (the psychiatric manual) as a pervasive developmental disorder (PDD).  Like other PDDs, it is marked by a loss of social engagement and language skills. Although it is a PDD, and appears next to "Autistic Disorder" in the DSM-IV,  it is not believed to belong to the category of autism spectrum disorders. Unlike autism spectrum disorders, which impact boys much more frequently than girls, Rett syndrome affects mostly females.  It also has a known genetic cause, at least in the vast majority of cases. It is due to this, and to the fact that a research registry already exists for Rett syndrome, that the IAN Research project is not collecting information from families with children with Rett syndrome.

What is Rett Syndrome?^*

Rett syndrome is a neurological and developmental disorder that mostly occurs in females. Infants with Rett syndrome seem to grow and develop normally at first, but then stop developing and even lose skills and abilities.

For instance, they stop talking even though they used to say certain words. They lose their ability to walk properly. They stop using their hands to do things and often develop stereotyped hand movements, such as wringing, clapping, or patting their hands.

Rett syndrome is considered one of the autism spectrum disorders. Most cases of Rett syndrome are caused by a mutation on the MECP2 gene, which is found on the X chromosome. For more information on the MECP2 gene, see the What causes Rett Syndrome? section of the Rett Syndrome publication of the National Institute of Child Health and Human Development (NICHD). 

What are the symptoms of Rett Syndrome?

Beginning between 3 months and 3 years of age, most children with Rett syndrome start to show some of the following symptoms:

• Loss of purposeful hand movements, such as grasping with fingers, reaching for things, or touching things on purpose
• Loss of speech
• Balance and coordination problems, including losing the ability to walk in many cases
• Stereotypic hand movements, such as hand wringing
• Breathing problems, such as hyperventilation and breath holding, or apnea when awake
• Anxiety and social-behavioral problems
• Intellectual disability/mental retardation

There are a number of other problems common among those who have Rett syndrome, but having these problems is not necessary to get a diagnosis of Rett syndrome. These problems can include:

• Scoliosis, a curving of the spine that occurs in approximately 80 percent of girls with Rett Syndrome
• Seizures
• Constipation and gastro-esophageal reflux
• Cardiac or heart problems, specifically problems with the rhythm of their heartbeat
• Problems feeding themselves; trouble swallowing and chewing
• Problems with sleep, specifically disrupted sleep patterns at night and an increase in total and daytime sleep.

For more details on symptoms of Rett syndrome and other associated problems, see What are the typical features of Rett Syndrome? in NICHD’s Rett Syndrome publication.

What is the usual course of Rett Syndrome?

Health care providers view the onset of Rett syndrome symptoms in four stages:

• Early Onset Phase – Development stalls or stops.
• Rapid Destructive Phase – The child loses skills (regresses) quickly. Purposeful hand movements and speech are usually the first skills lost.
• Plateau Phase – Regression slows, and other problems may seem to lessen or improve. Most people with Rett syndrome spend most of their lives in stage 3.
• Late Motor Deterioration Phase – Individuals may become stiff or lose muscle tone; some may become immobile.

Most girls with Rett syndrome live until adulthood. They will usually need care and assistance throughout their lives.

What is the treatment for Rett syndrome?

There is currently no cure for Rett syndrome. However, girls can be treated for some of the problems associated with the condition. These treatments generally aim to slow the loss of abilities, improve or preserve movement, and encourage communication and social contact.

People with Rett syndrome often benefit from a team approach to care, in which many kinds of health care providers play a role, along with family members. Members of this team may include:

• Physical therapists, who can help patients improve or maintain mobility and balance and reduce misshapen back and limbs
• Occupational therapists, who can help patients improve or maintain use of their hands and reduce stereotypic hand movements.
• Speech-language therapists, who can help patients use non-verbal ways of communication and improve social interaction.

Other options, such as medication (for constipation or heart problems) or surgery (to correct spine curvature or correct heart defects) are also effective for treating some of the symptoms of Rett syndrome. For more details on treatment, see the Are there treatments for Rett syndrome? section of NICHD’s Rett Syndrome publication.

For additional information, you may also want to read the Rett Syndrome fact sheet available via the National Institute of Neurological Disorders and Stroke (NINDS). 

*This information provided courtesy of the National Institute of Child Health and Human Development.