Autism is a pervasive developmental disorder. There are other disorders that fall into this classification which can be misdiagnosed as autism.
Rett syndrome is one of these disorders:
Rett syndrome is a disorder of the nervous system that leads to developmental reversals, especially in the areas of expressive language and hand use.
Rett syndrome occurs almost exclusively in girls and may be misdiagnosed as autism or cerebral palsy.
Studies have linked many Rett syndrome cases to a defect in the methl-CpG-binding protein 2 (MeCP2) gene. This gene is on the X chromosome. Females have two X chromosomes, so even when one has this significant defect, the other X chromosome is normal enough for the child to survive.
Males born with this defective gene do not have a second X chromosome to make up for the problem. Therefore, the defect usually results in miscarriage, stillbirth or very early death.
The condition affects about 1 out of 10,000 children. Groups of the disease have appeared within families and certain geographic regions, including Norway, Sweden, and northern Italy.
An infant with Rett syndrome usually has normal development for the first 6 – 18 months. Symptoms range from mild to severe.
***Check out the article for symptoms***
Genetic testing may be done to look for the gene defect associated with the syndrome. However, since the defect is not identified in everyone with the disease, the diagnosis of Rett syndrome is based on symptoms.
Outlook and prognosis:
The disease slowly progresses until the patient is a teenager. Then, symptoms may improve. For example, seizures or breathing problems tend to lessen in late adolescence.
Developmental regression or delays vary. Usually, a child with Rett syndrome sits up properly but may not crawl. For those who do crawl, many do so by scooting on their tummy without using their hands.
Similarly, some children walk independently within the normal age range, while others are delayed, don’t learn to walk independently at all, or don’t learn to walk until late childhood or early adolescence. For those children who do learn to walk at the normal time, some keep that ability for their lifetime, while other children lose the skill.
Life expectancies are not well studied, although survival at least until the mid-20s is likely. The average life expectancy of a girl with Rett syndrome may be mid-40s. Death is often related to seizure, aspiration pneumonia, malnutrition, and accidents.
You can kind of see how this might be misdiagnosed as Autism, especially in a child’s early development. It is definitely a very similar disease, being in the pervasive developmental disorder category. But from what I found on Rett Syndrome, it is so much more severe than autism. I’m glad to find this information, since it seems so many of these disorders are lumped into one name, autism, when actually they are quite different.