Rett Syndrome

Definition

Rett Syndrome is a developmental nervous system disorder primarily affecting girls. It is uncommon but not rare, occurring in 1 out of every 10,000-23,000 female births. Boys with the gene defect that causes this disorder are usually stillborn or die shortly after birth. There are two types of Rett Syndrome depending on the symptoms. The two types are classic and atypical. Many people with Rett Syndrome live into adulthood. Some cannot talk or walk. They usually have a full range of feelings and often communicate through their eyes. They usually require daily care from someone else.

Causes

The majority of cases of Rett Syndrome are caused by nonhereditary, acquired changes or mutations in the Rett Syndrome gene on the X chromosome. (Females have two X chromosomes and males have one X and one Y chromosome.) The gene responsible for Rett Syndrome also controls the functions of several other genes. In patients with Rett Syndrome a genetic mutation causes the body to begin producing too much of a protein called methyl cytosine binding protein 2 (MECP2). The excess protein damages the nervous system. This results in symptoms typical of patients with Rett syndrome. It is unknown what causes the genetic mutation.

Risk Factors

A risk factor is something that increases your chances of getting a disease or condition. There are no known risk factors for Rett Syndrome except being female.

Symptoms

A girl with Rett Syndrome will start developing normally. She will smile, move, and pick items up with her fingers. But by 18 months of age, the developmental process seems to stop or reverse itself. The age of onset and the severity of symptoms can vary. There are four stages. Symptoms include:
Stage I: Early Onset Stage – Age: 6-18 months. Duration: months.
Symptoms may include:
  • Less eye contact with parents
  • Less interest in toys and play
  • Hand wringing
  • Slow head growth
  • Calm, quiet baby
Stage II: Rapid Destructive Stage – Age: 1-4 years. Duration: weeks to months. Symptoms may include:
  • Small head
  • Mental retardation
  • Loss of muscle tone
  • Inability to purposely use hands
  • Loss of (previous) ability to talk
  • Repeatedly moving hands to mouth
  • Other hand movements, such as clapping, tapping, or random touching
  • Hand movements stop during sleep
  • Holding breath, gaps in breathing, taking rapid breaths
  • Irregular breathing stops during sleep
  • Teeth grinding
  • Laughing or screaming spells
  • Decreased social interactions
  • Irritability
  • Trouble sleeping
  • Tremors
  • Cold feet
  • Trouble crawling or walking
Stage III: Plateau Stage – Age: Preschool through school years. Duration: years. Symptoms may include:
  • Difficulty controlling movement
  • Seizures
  • Less irritability and crying
  • Communication may improve
Stage IV: Late Motor Deterioration Stage – Age: When stage III ceases, can be anywhere from age 5 to 25. Duration: Up to decades. Symptoms may include:
  • Decreased ability to walk
  • Muscle weakness or wasting
  • Stiffness of muscles
  • Spastic movements
  • Scoliosis (curvature of the spine)
  • Breathing trouble and seizures often decrease with age
  • Puberty usually begins at the expected age

Diagnosis

The doctor will ask about your child’s symptoms and medical history, and perform a physical and neurological exam. Evaluation can exclude other disorders such as autism. Genetic testing can often confirm the diagnosis.
Tests may include:
  • Blood test – to check for the responsible genetic mutation (MECP2)
  • Electroencephalogram (EEG) – a test that records the electrical activity of the brain
  • Video-EEG – a test that combines EEG with a video to see if some of the child's movements are caused by seizures.

Treatment

There is no cure for Rett Syndrome. People with this disease need to be monitored for skeletal and heart problems that may develop later in the disease.
Treatment aims to control symptoms and includes:
Medication
  • Anticonvulsants to control seizure activity
  • Stool softeners or laxatives if constipated
  • Drugs to help with breathing
  • Drugs to ease agitation
Nutrition Support
  • Small, frequent meals
  • Supplements
  • Tube feeding, if the patient is unable to consume enough food
  • Fluids and high-fiber foods to help control constipation
Rehabilitation Therapies
  • Occupational therapy helps patients learn to perform daily activities, such as dressing and eating.
  • Physical therapy helps patients improve coordination and movement. It can sometimes prolong the ability to walk.
  • Therapists can recommend braces and splints.
  • Speech therapy aids in building communication skills.
  • Social workers help a family cope with caring for a child with Rett syndrome. Counselors help parents learn to manage behaviors.
Techniques for Limiting Problem Behaviors
Keeping a diary of the child's behaviors and activities helps in determining the cause of agitation. The following may help to prevent or control behavior problems:
  • Warm baths
  • Massage
  • Soothing music
  • A quiet environment

Prevention

There are no guidelines for the prevention of Rett syndrome because the cause is unknown. If you have any questions about the risk of Rett Syndrome in your family, you can talk to a genetic counselor.