Symptoms:

An infant with Rett syndrome usually has normal development for the first 6 - 18 months. Symptoms range from mild to severe.

Symptoms may include:

• Hypotonia (floppy arms and legs) -- frequently the first sign
• Slowing head growth beginning at approximately 5 - 6 months of age
• Change in development
• Severe language development problems
• Loss of purposeful hand movements; for example, the grasp used to pick up small objects is replaced by repetitive hand motions like hand wringing or constant placement of hands in mouth
• Apraxia
• Shaky, unsteady, or stiff gait; or toe walking
• Loss of social engagement
• Seizures
• Breathing problems -- problems tend to get worse 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
• 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 problems including ongoing, severe constipation and gastroesophageal reflux (GERD)
• Excessive saliva and drooling

Signs and tests:

Genetic tests may be used to search for the gene mutations that cause Rett syndrome. However, since this gene defect 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 early (soon after birth) or late (beyond 18 months of age, sometimes as late as 3 or 4 years old).
• Speech and hand skill problems are mild.
• It is found in a boy (very rare).