Rett syndrome affects about 1 in 10,000 females. It is now believed, however, that the prevalence of Rett may be much higher. Males can also be afflicted and typically have earlier onset of symptoms with significant problems beginning at or shortly after birth. Rett syndrome leaves all children dependent on others for all of their basic needs such as feeding, dressing, bathing and toileting.
The disorder was identified by Dr. Andreas Rett, an Austrian physician who first described it in a journal article in 1966. It was not until a second article about the disorder was published in 1983 that the disorder was recognized in the United States.
The course of Rett syndrome, including the age of onset and the severity of symptoms, varies from child to child. The child with Rett appears to grow and develop normally and then between six to 18 months of age, mental and physical symptoms appear. Hypotonia (loss of muscle tone) is usually the first symptom. As the syndrome progresses, most children lose purposeful use of their hands and the ability to speak. Other early symptoms may include problems crawling or walking and diminished eye contact. For many, the loss of functional use of the hands is followed by repetitive hand movements such as wringing, washing, or mouthing. The onset of this period of regression is sometimes sudden.
Symptoms of Rett syndrome may also include apraxia (the inability to perform motor functions), toe walking, sleep problems, wide-based gait, teeth grinding, and difficulty chewing, slowed growth, seizures, cognitive disabilities and breathing irregularities while awake such as hyperventilation, apnea (breath holding) and air swallowing.