Rett syndrome

Injury	Disease	Nutrition	Poison

Symptoms	Surgery	Test	Special Topic

Rett syndrome

Symptoms:

An infant with Rett syndrome usually has normal development for the first 6-18 months. Once symptoms do begin, they vary greatly from mild to severe. In fact, there are at least six variants that have been identified to date. In addition, there seem to be four distinct stages of the disease. See the International Rett Syndrome Association website for additional information about these stages.

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Symptoms may include:

Hypotonia (floppy arms and legs) -- frequently the first sign
Slowing head growth beginning at approximately 5-6 months of age
Developmental regression
Severely impaired language development
Loss of purposeful hand movements; for example, the pincer grasp used to pick up small objects is replaced by repetitive hand motions like hand wringing or constant placement of hands in mouth
Apraxia -- partial or complete inability to carry out purposeful movements
Shaky, unsteady, or stiff gait; or toe walking
Loss of social engagement
Seizures (1/3 of patients)
Intermittent hyperventilation with a disorganized breathing pattern, air swallowing, and breath holding
Breathing abnormalities tend to worsen with stress; breathing is usually normal during sleep and abnormal while awake
Scoliosis
Loss of normal sleep patterns
Poor circulation that can lead to cold and bluish arms and legs, and small feet
Intellectual disabilities and learning difficulties (assessing cognitive skills in those with Rett syndrome, however, is difficult because of the speech and hand motion abnormalities)
Gastrointestinal complaints including ongoing, severe constipation and gastroesophageal reflux (GERD)
Sleep disturbances
Excessive saliva and drooling

Signs and tests:

Chromosomal analysis may now be used to search for the gene mutations that cause Rett syndrome. Studies have shown that mutations of the MeCP2 gene can be found in 75% of girls with Rett syndrome.

However, since this gene abnormality is not identified in everyone with the disease, the diagnosis of Rett syndrome is still based on the symptoms.

There are several different types of Rett syndrome:

Classical (meets the diagnostic criteria)
Provisional (some evidence between ages 1 and 3)
Atypical

Rett syndrome is classified as atypical if:

It begins earlier (soon after birth), or later (beyond 18 months of age, sometimes as late as 3 or 4 years old)
Speech and hand skill abnormalities are milder
It is found in a boy (very rare). One boy with Rett syndrome did not have the MECP2 gene mutation in every copy of the gene in his body. In another case, the boy was XXY -- that is, he had an extra X chromosome.