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Rett Syndrome


Stephen J. Falchek

, MD, Nemours/Alfred I. duPont Hospital for Children

Reviewed/Revised Jul 2023

Rett syndrome is a rare neurodevelopmental disorder caused by a genetic problem that occurs almost exclusively in girls and affects development after an initial 6-month period of normal development.

  • Rett syndrome is caused by a genetic mutation.

  • Symptoms include a decline in language and social skills after an initial period of normal development.

  • Diagnosis is based on a doctor's observation of the child’s early growth and development and genetic testing.

  • Treatment involves a multidisciplinary approach that is focused on the management of symptoms and educational support.

Rett syndrome is a rare neurodevelopmental Definition of Developmental Disorders Developmental disorders are better called neurodevelopmental disorders. Neurodevelopmental disorders are neurologically based conditions that can interfere with the acquisition, retention, or... read more and genetic disorder diagnosed most often in girls. Affected boys are identified much less often than girls because affected male fetuses often die before birth. Girls with Rett syndrome are usually born after a full-term, uneventful pregnancy and delivery.

Rett syndrome is caused by mutation of a gene or genes that are needed for brain development.

It causes impaired social interactions, loss of language skills, and repetitive hand movements. Although many symptoms resemble those of an autism spectrum disorder Autism Spectrum Disorders Autism spectrum disorders are conditions in which people have difficulty developing normal social relationships, use language abnormally or not at all, and show restricted or repetitive behaviors... read more , including difficulties with social skills and communication, Rett syndrome is a separate disorder.

Symptoms of Rett Syndrome

Girls with Rett syndrome appear to develop normally until some time between 6 months and 18 months of age.

When the disorder begins, head growth slows and language and social skills deteriorate. As the disorder progresses, children typically display repetitive hand motions resembling washing or wringing. Purposeful hand movements are lost, walking is impaired, and trunk movements are clumsy. Breathing problems may occur. Intellectual disability Intellectual Disability Intellectual disability is significantly below average intellectual functioning present from birth or early infancy, causing limitations in the ability to conduct normal activities of daily... read more develops and is usually severe. Seizures Seizures in Children Seizures are a periodic disturbance of the brain’s electrical activity, resulting in some degree of temporary brain dysfunction. When older infants or young children have seizures, they often... read more often occur, and over time mobility may be affected. Later, children may develop scoliosis Scoliosis Scoliosis is abnormal curvature of the spine. Scoliosis can be present at birth or can develop during adolescence. Mild forms may cause only mild discomfort, but more severe forms can cause... read more Scoliosis and often have heart problems. They may have slowed growth and tend to have difficulty maintaining weight.

Slight spontaneous improvements in social interaction may occur in late childhood and early adolescence, but the language and hand behavior problems remain.

Diagnosis of Rett Syndrome

  • A doctor's evaluation

  • Genetic testing

Doctors make the diagnosis of Rett syndrome by observing symptoms during the child’s early growth and development and by following established criteria. Ongoing evaluation of the child’s physical and neurologic status is needed.

Genetic testing for the mutated gene and other genes is done to confirm the diagnosis.

Treatment of Rett Syndrome

  • Medical team support

  • Special education support

  • Management of symptoms

  • Treatment of seizures and hand behavior problems with antiseizure and behavioral medications

  • Possibly trofinetide

There is no cure for Rett syndrome.

The most helpful treatment of Rett syndrome is with a medical team approach that includes physical, occupational, and speech/language therapists. Most people with Rett syndrome need extensive support and specialized educational programs.

Doctors may give medications to control seizures and hand behavior problems, help relieve breathing problems, or to help problems with movement.

Trofinetide is a medication available for the treatment of Rett syndrome in adults and children who are 2 years of age and older.

Regular medical re-evaluations are needed to monitor the progression of scoliosis and to monitor heart problems.

Nutrition support may be needed to help affected children maintain their weight.

The federal Individuals with Disabilities Education Act (IDEA) requires public schools to provide free and appropriate education to children and adolescents with Rett syndrome. Education must be provided in the least restrictive, most inclusive setting possible—that is, a setting where the children have every opportunity to interact with nondisabled peers and have equal access to community resources. The Americans with Disability Act and Section 504 of the Rehabilitation Act also provide for accommodations in schools and other public settings.

Prognosis for Rett Syndrome

The long-term prognosis, including expected life span, is variable. However, usually children survive well into adulthood with the support of a medical team. Many factors, including how well seizures are controlled, whether the person retains the ability to walk, and nutrition, affect the prognosis.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

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