Rett syndrome is a problem with the development of the nervous system. It is most common in girls. Rett syndrome occurs in one out of every 10,000-23,000 female births.
Boys with Rett syndrome are usually stillborn or die shortly after birth.
Rett syndrome can be classified into
classic
and
atypical based on the symptoms.
Many people with Rett syndrome live into adulthood. Most have severe disabilities including an inability to talk or walk. People with Rett syndrome usually have a full range of feelings and often communicate through their eyes. Daily care throughout their life is often needed.
Rett syndrome is most often caused by nonhereditary mutations on a specific gene on one X chromosome.
Females have two X chromosomes. Males have one X and one Y chromosome. Males usually die from Rett syndrome because they lack a second normal X chromosome. The second normal X chromosome in girls may provide some protection.
In Rett syndrome, the mutated gene affects methyl cytosine binding protein 2 (called MECP2). When it is mutated, there is a deficiency of this important protein. This is an area that is still being studied.
Ninety-five percent of girls with Rett Syndrome and 50% of those with the atypical form have the MECP2 mutation. But, not everyone with this mutation will have Rett syndrome. Some females may be normal or have only mild symptoms. But, these women can pass the gene to their daughters. The daughters may then be more severely affected.
It is not clear what causes the Rett gene to mutate. Rett syndrome is usually nonhereditary. This means it does not run in families.
There are no known risk factors for Rett syndrome, except being female. The mutation that causes the syndrome appears to be sporadic.
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 is different from person to person. There are four stages. Symptoms for each stage include:
Occurs at age 6 to 18 months
Can last for months and include
Less eye contact with parentsLess interest in toys and playHandwringingSlow head growthCalm, quiet baby Occurs at age 1 to 4 years
Can last weeks to months and include:
Small headIntellectual disabilityLoss of muscle toneInability to purposely use handsLoss of (previous) ability to talkRepeatedly moving hands to mouthOther hand movements, such as clapping, tapping, or random touchingHand movements stop during sleepHolding breath, gaps in breathing, taking rapid breathsIrregular breathing stops during sleepTeeth grindingLaughing or screaming spellsDecreased social interactionsIrritabilityTrouble sleepingTremorsCold feetTrouble crawling or walking Occurs at age preschool through school years
Can last for years and include:
Difficulty controlling movementSeizuresLess irritability and cryingCommunication may improve Occurs at age when stage III ceases, can be anywhere from age 5 to 25
Can last up to decades and include:
Decreased ability to walkMuscle weakness or wastingStiffness of musclesSpastic movementsScoliosis
(curvature of the spine)
Breathing trouble and seizures often decrease with agePuberty usually begins at the expected age
The doctor will ask about your child’s symptoms and medical history. A physical and neurological exam will be done. Genetic testing can often confirm the diagnosis. Your doctor may also do tests to rule out other conditions like
autism
.
Some symptoms of Rett syndrome are similar to those of autism. Children with autism, who are more often boys, do not maintain person-to-person contact. Most girls with Rett syndrome, though, prefer human contact to focusing on inanimate objects. These differences may give the first clue in diagnosing Rett syndrome.
Physical and developmental symptoms can often lead your doctor to a Rett syndrome diagnosis.
Tests that may be done include:
Blood test—to check for 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 seizuresThere is no cure for Rett syndrome. People with this condition need to be monitored for problems of the bones and heart.
Treatment aims to control symptoms and includes:
Medications that may help with symptoms include:
Anticonvulsants to control seizure activityStool softeners or laxatives if constipatedDrugs to help with breathingDrugs to ease agitationHistone deacetylase inhibitors—a group of medications that are being investigated to treat Rett syndrome.To support nutrition, your doctor may recommend:
Small, frequent mealsSupplementsTube feeding
, if the patient is unable to consume enough food
Fluids and high-
fiber
foods to help control
constipationThese therapies will help manage physical and general care challenges:
Occupational therapy—to help patients learn to perform daily activities, such as dressing and eatingPhysical therapy—to help patients improve coordination and movement (can sometimes prolong the ability to walk), braces and splints may be recommendedSpeech therapy aids—to build communication skillsSocial workers—to help a family cope with caring for a child with Rett syndromeKeeping a diary of your child's behaviors and activities helps determine the cause of agitation. The following may help to prevent or control behavior problems:
Warm bathsMassageSoothing musicQuiet environmentThere is no way to prevent Rett syndrome. If you have questions about the risk of Rett syndrome in your family, talk to a genetic counselor.