Rett syndrome (RTT) is characterized by abnormal social and language development and accopmained by repetitive behaviours. In this way it is similar to autism.
The onset of the disorder is not evident from birth but may occur between 5-30month and is accompainied by a deceleration in head growth.
Loss of muscle tone is usually the first symptom.
Other early symptoms may include problems crawling or walking and diminished eye contact.
As the syndrome progresses, a child will lose purposeful use of her hands and the ability to speak.
Two common features are the loss of purposeful hand movements and the development of stereotyped hand-washing movements.
The inability to perform motor functions is perhaps the most severely disabling feature of Rett syndrome, interfering with every body movement, including eye gaze and speech.
The prevalence of RTT is 1 per 10,000 females (almost exclusively female condition).
