Rett syndrome is a rare disorder which is primarily seen in girls. Cases of the syndrome were first described by Andreas Rett in 1966, with additional cases reported in the 1980s, leading to widespread recognition of Rett syndrome in the medical community. This condition is a sex-linked disorder which involves errors on the X chromosome, and it is much more common in girls than boys, primarily because male fetuses with Rett syndrome usually die before birth.
This neurodevelopmental condition is not inherited, but rather caused by errors in fetal development which lead to abnormalities on the X chromosome. In very rare cases, a mother with a mild case who is asymptomatic may pass on a damaged X chromosome to an infant, resulting in an inherited case of Rett syndrome. Genetic testing can confirm a diagnosis of Rett syndrome, although the symptoms are usually enough for a doctor to make a confident diagnosis.
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There are four stages to this condition. During early development, the child is normal, reaching expected developmental milestones and behaving as expected. In the early onset phase, however, the child starts to experience problems with muscle coordination, and may exhibit early signs of what can appear to be autism. The early onset phase of Rett syndrome usually happens between six and 18 months of age, and the condition may not be diagnosed at first because the symptoms are subtle.
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In the rapid destructive phase, the patient begins to experience extreme developmental and neurological problems which include a slowing of the growth of the hands, feet, and head. The patient may develop cardiac abnormalities, seizures, muscle weakness, breathing problems, scoliosis, an increasing lack of coordination, and behavioral problems. Some patients remain nonverbal.
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During the plateau phase, the patient reaches a fairly stable point, with no additional degeneration or progression. Eventually, in the late motor deterioration phase of Rett syndrome, the patient starts to experience serious mobility problems. Cognition may improve slightly during this phase.
Rett syndrome cannot be cured, but there are treatments which can be used to manage the condition and to keep the patient comfortable. Treatments revolve around treating symptoms as they arise, and providing occupational, physical, and psychological therapy to the patient to improve socialization and motor skills. The severity of Rett syndrome can vary, as with many genetic conditions, depending on individual variations within the patient. Some patients are severely impaired, while others may enjoy more normal function; in all cases, therapy can help the patient live a more active and happy life.