Rett syndrome is a neurodevelopmental disorder that affects girls almost exclusively. It is characterized by normal early growth and development followed by a slowing of development, loss of purposeful use of the hands, distinctive hand movements, slowed brain and head growth, problems with walking, seizures, and intellectual disability.
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 after a second article about the disorder, published in 1983 by Swedish researcher Dr. Bengt Hagberg, that the disorder was generally recognized.
The course of Rett syndrome, including the age of onset and the severity of symptoms, varies from child to child. Before the symptoms begin, however, the child generally appears to grow and develop normally, although there are often subtle abnormalities even in early infancy, such as loss of muscle tone, difficulty feeding, and jerkiness in limb movements. Then, gradually, mental and physical symptoms appear. As the syndrome progresses, the child loses purposeful use of her hands and the ability to speak. Other early symptoms may include problems crawling or walking and diminished eye contact. The loss of functional use of the hands is followed by compulsive hand movements such as wringing and washing. The onset of this period of regression is sometimes sudden.
Apraxia most severely disabling feature of Rett syndrome, interfering with every body movement, including eye gaze and speech.
Children with Rett syndrome often exhibit autistic-like behaviors in the early stages. Other symptoms may include walking on the toes, sleep problems, a wide-based gait, teeth grinding and difficulty chewing, slowed growth, seizures, cognitive disabilities, and breathing difficulties while awake such as hyperventilation, apnea (breath holding), and air swallowing.
Doctors clinically diagnose Rett syndrome by observing signs and symptoms during the child’s early growth and development, and conducting ongoing evaluations of the child’s physical and neurological status. Scientists have developed a genetic test to complement the clinical diagnosis, which involves searching for the MECP2 mutation on the child’s X chromosome.
Treatment for the disorder is symptomatic — focusing on the management of symptoms — and supportive, requiring a multidisciplinary approach. Medication may be needed for breathing irregularities and motor difficulties, and anticonvulsant drugs may be used to control seizures. There should be regular monitoring for scoliosis and possible heart abnormalities. Occupational therapy can help children develop skills needed for performing self-directed activities (such as dressing, feeding, and practicing arts and crafts), while physical therapy and hydrotherapy may prolong mobility. Some children may require special equipment and aids such as braces to arrest scoliosis, splints to modify hand movements, and nutritional programs to help them maintain adequate weight. Special academic, social, vocational, and support services may be required in some cases.