Rett syndrome

Related Terms

Brain disorder, chromosomal disorder, developmental disorder, genetic disorder, genetic mutation, inherited disorder, MECP2, methl-CpG-binding protein 2, neurodevelopmental disorder, neurological disorder, sex-linked trait, PDD, pervasive development disorder, X-chromosome, X-linked dominant trait.

Background

Rett syndrome (RTT) is a rare brain disorder that occurs almost exclusively in females. Most experts believe Rett syndrome is a neurodevelopmental disorder, rather than a condition that worsens over time.
Female infants with Rett syndrome appear to develop normally at first, but once they reach 6-18 months of age, they stop developing and lose most of their previously developed skills, such as speaking or making purposeful movements with their hands. Eventually, these patients grow up to become intellectually disabled (formerly called mentally retarded). If Rett syndrome occurs in male fetuses, it leads to miscarriage, stillbirth, or death during infancy.
Rett syndrome is caused by a mutated gene that randomly occurs for unknown reasons. Researchers estimate that Rett syndrome occurs in 1 out of 10,000-23,000 births each year worldwide.
Because Rett syndrome affects the way the brain grows and develops, the condition is classified as a pervasive development disorder (PDD).
There is currently no cure for Rett syndrome. In females, the disease typically stops progressing for many years when the child is 2-10 years of age. Most females live to be 40-50 years of age. Males, on the other hand, often die before birth. Males that are born alive usually die during infancy. Treatment for Rett syndrome focuses on improving the patient's functional and communication skills. Patients require lifelong care and support and help with daily tasks, such as eating, walking, and toileting.

Signs and symptoms

General: Males with Rett syndrome often die before birth. Females typically develop normally until they are 6-18 months of age. There are four basic stages of Rett syndrome, each of which causes different symptoms. However, symptoms vary among patients from mild to severe, depending on the severity of their genetic mutations. Patients generally require lifelong care and support to perform daily tasks.
Stage I (early onset): Rett syndrome is usually not apparent at birth, and many infants appear to develop normally until they are about 6-18 months old. The first stage of Rett syndrome occurs when the patient is 6-18 months of age. Symptoms during this stage usually go unnoticed. Babies might make less eye contact and/or start to lose interest in their toys. There may be delays in motor skills such as sitting up or crawling. This stage typically lasts a few months, but it may last longer than one year.
Stage II (rapid destructive stage): Stage II, also called the rapid and destructive stage, typically occurs when the child is between the ages of one and four years old. Symptoms in this stage usually develop quickly. During this stage, children start to lose skills they had learned earlier. For instance, children typically lose their ability to speak or move their hands purposefully. In addition, hand movements including wringing, washing, clapping, or tapping, as well as repeatedly moving the hands to the mouth, develop. Children may breathe irregularly, and episodes of hyperventilation and apnea may occur. Breathing is usually normal during sleep. Children may exhibit autistic-like behaviors and have difficulty interacting or communicating with others. Other symptoms may include irritability, sleep disturbances, unsteady gait, and slowed head growth.
Stage III(plateau or psudeo-stationary stage): The third stage, which can last for years, generally occurs when the child is between the ages of two and 10. During this stage, patients typically experience apraxia, or the inability to perform controlled motor movements. This condition is one of the most disabling symptoms of Rett syndrome because it can make it difficult for patients to walk, talk, control their eye gazes, and other movements. Children may also have poor balance and experience seizures. Although problems with mobility and muscle control continue during this stage, there may be improvements in the patient's behavior. The child may be less irritable, show signs of increased alertness, and experience improvements in nonverbal communication skills. Behavioral improvements vary among individuals. For many patients, the disorder stays at stage III for the rest of their lives.
Stage IV (late motor deterioration): Stage IV, also called the late motor deterioration stage, is the last phase of the disorder. During this stage, which can last for years to decades, patients suffer from reduced mobility. Patients may lose their ability to walk. Common symptoms include muscle weakness and stiffness, spasticity, increased muscle tone with abnormal body posture, and curvature of the spine (called scoliosis). There is usually no decline in communication, cognition, or hand skills. Repetitive hand movements may decrease.

Diagnosis

Rett syndrome may be diagnosed if the patient meets the following criteria: 1) The patient developed normally until the age of 6-18 months. 2) The child has normal head circumference at birth, followed by slowed head growth. 3) Repetitive hand movements, such as wringing, tapping, clasping, or clapping, develop. 4) The patient has severely impaired language and communication skills. 5) The patient's torso shakes. 6) The patient walks on her toes and/or has an unsteady and wide gait.
If the patient meets the criteria to be diagnosed with Rett syndrome, a genetic test may be performed to confirm a diagnosis. A sample of the patient's blood is tested to determine if the mutated gene is present. If the mutated gene is in the blood, a positive diagnosis is made.

Complications

Death: Patients typically live to be about 40-50 years old. Most deaths are caused by seizures, malnutrition, aspiration, pneumonia, or accidents.
Irregular heartbeat: Patients with Rett syndrome may develop irregular heartbeats, called cardiac arrhythmias.
Bone fractures: Individuals with Rett syndrome have an increased risk of developing osteoporosis, a condition that causes the bones to become brittle and porous. As a result, these patients have an increased risk of breaking bones.
Malnutrition: It is difficult for patients to feed themselves. Because voluntary motor control is reduced, patients may also have difficulty chewing and swallowing food. As a result, some patients may be shorter and weigh less than other children the same age. In order to ensure that the patient is receiving enough nutrition, some patients may need to be fed through tubes in their stomachs.

Treatment

General: There is currently no cure for Rett syndrome. Instead, treatment focuses on managing the symptoms of the disorder.
Anticonvulsants: Patients who develop seizures may benefit for anticonvulsant drugs. These drugs may also help improve a patient's mood and/or behavior. These drugs are typically taken once daily to help prevent seizures from occurring. Phenobarbital (Luminal? Sodium) is one of the oldest and safest anticonvulsants for children. Valproic acid (Depakene? or Depakote?) has also been shown to be a safe and effective treatment for seizures.
Occupational therapy: Patients may also benefit from occupational therapy. During sessions, a therapist helps the child learn skills to help them perform basic daily tasks, such as feeding, dressing, and communicating with others. There are therapists who specialize in patients with disorders and disabilities, including Rett syndrome. Parents and caregivers can ask their children's pediatricians for recommended therapists.
Education: Some patients with Rett syndrome are educated in mainstream classrooms. Some attend public schools but take special education classes, while others attend specialized schools that are designed to teach children with disabilities. Experts also recommend exposing children to age-appropriate toys and books. Even if the child appears to be unresponsive to such stimuli, it may not be the case. This is because it is often difficult to measure a patient's cognitive abilities due to apraxia and a lack of communication skills.
Braces: Patients with scoliosis may benefit from back braces. Although these braces do not cure scoliosis, they have been shown to prevent the condition from worsening. During treatment, the curve may improve by as much as 50%. However, once the brace is discontinued, the spine will go back to its original curve. Children and adults who wear braces can move without much restriction.
Surgery: Orthopedic surgery may be needed for patients who develop scoliosis. Surgery is performed if the patient's curve is greater than a 40- to 50-degree angle. During surgery, the vertebrae along the curve are fused, or joined together, in order to straighten the spine. After surgery, the patient remains hospitalized for several days and recovery is several months. Complications may include bleeding, infection, pain, nerve damage, arthritis, and disk degeneration. If the surgery is unsuccessful, another surgery may be necessary.
Physical therapy: Physical therapy may help patients improve their physical strength and flexibility. This may help improve the patient's control of voluntary muscles and help improve or maintain the patient's walking skills. A variety of techniques, including exercises, stretches, traction, electrical stimulation, and massage, are used during physical therapy sessions.

Integrative therapies

Unclear or conflicting scientific evidence:
L-carnitine: The human body produces L-carnitine in the liver, kidney, and brain. Early evidence suggests that L-carnitine may be a beneficial treatment for patients with Rett syndrome. However, addition research is needed before a firm conclusion can be made.
Avoid if allergic to L-carnitine. Use cautiously with peripheral vascular disease, high blood pressure, alcohol-induced liver cirrhosis, or diabetes. Use cautiously in low birth weight infants and individuals on hemodialysis. Use cautiously if taking anticoagulants (blood thinners), beta-blockers, or calcium channel blockers. Avoid if pregnant or breastfeeding.

Prevention

Currently, there is no known method of prevention for Rett syndrome. However, there is a less than one percent chance of having a baby with Rett syndrome.
Early diagnosis and prompt treatment may help improve a patient's long-term prognosis.
Because Rett syndrome is rare and it occurs randomly in infants, prenatal testing is not typically performed.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

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Causes

Rett syndrome is a genetic disorder. However it is not usually passed down from parents to their children. Instead, most mutations occur randomly.
Rett syndrome affects females almost exclusively because the mutated gene that causes the disorder is found on the X chromosome. This mutated gene is called the methl-CpG-binding protein 2 (MeCP2) gene. Rett syndrome is an X-linked dominant trait. That means individuals will have the disorder if they have just one copy of the mutated chromosome.
Females have two X chromosomes, while males have one X and one Y chromosome. Although females with one mutated X chromosome have Rett syndrome, their symptoms are less severe than a male's would be. This is because the normal X chromosome inactivates the mutated X chromosome in some of the body's cells.
Since males have only one X chromosome, all of their cells have the mutated gene, and they cannot live past infancy.

Tips for the caregiver

Caring for a patient with Rett syndrome can be emotionally and physically tiring at times. Parents or caregivers should make time to relax and enjoy their favorite activities. Many families receive help from outside caregivers. Families may also choose residential care, especially when the child becomes an adult.
Siblings of a child with Rett syndrome may feel left out or jealous of the attention that their sister receives from their parents. Therefore, parents should make an effort to spend one-on-one time with their other children.
Families of someone with Rett syndrome may benefit from counseling or psychotherapy sessions. These therapies may help family members cope with their loved one's illness.
Caregivers may find support from other families who are caring for patients with Rett syndrome. Many communities have local support groups for parents, family members, and caregivers of patients with the disorder. There are also many online support groups, which include chat rooms and message boards. Support groups allow individuals to talk with others who share the same challenges.
Caregivers should educate themselves about Rett syndrome. The more a caregiver knows about the condition, the better they can help the patient. Being educated on Rett syndrome may also help the caregiver learn how to communicate better with the child.