by Kimberly Allen, RN
Rett syndrome is a genetic neurodevelopmental disorder that used to be called cerebroatrophic hyperammonemia. It affects the grey matter in the brain and affects girls almost exclusively. Though it also affects all races and ethnic groups it rarely affects boys. However, in boys that do develop Rett syndrome it is much more severe because they only have one X chromosome therefore the condition is quickly fatal and they usually die soon after birth.
Rett syndrome is caused by a genetic mutation in a gene located on the x chromosome known as MECP2. Although Rett syndrome is a genetic disorder 95% of the time the condition results from a spontaneous mutation in the gene. In other words it isn’t inherited from either parent, in fact in most cases neither parent have the MECP2 mutation. Because Rett syndrome occurs mainly in girls many researchers believe the mutation occurs in the X chromosome donated by the father. The exact function of the MECP2 gene is unclear just as how a mutation in this gene leads to Rett syndrome is unclear. There are many researchers that believe the MECP2 gene influences numerous other genes that are involved in development.
The progress of Rett syndrome varies from child to child including the age of your child when symptoms develop as well as the severity of her symptoms. The symptoms of Rett syndrome progresses in 4 stages. The child is usually between 6 to 18 months old in the first stage. Frequently the symptoms in this stage are missed because they tend to be vague. It starts with a subtle slowing of development that can go unnoticed including a slowing of head growth. You may notice your baby is less interested in her toys and doesn’t make eye contact as often. You may also notice your child doesn’t start crawling or sitting at the expected point in development. The first stage usually lasts anywhere from a few months to over a year. Stage II is also known as the rapid destructive stage usually manifests when your child is between 1 to 4 years of age and can last from weeks to months. In this stage your child loses spoke language as well as purposeful hand skills like clapping and washing her hands as well as the ability to bring her hand to her mouth like when feeding herself. You may notice that she holds her hands either at her side or behind her back as well as random touching with grasping and releasing. These movements will disappear when she goes to sleep only occurring while she is awake. She may also experience episodes of apnea and hyperventilation while she is awake that tends to improve when she is asleep. Frequently girls also demonstrate autistic like symptoms like loss of communication and social interaction skills which is why it is also considered a form of autism. In the third stage your child reaches a plateau that can last for years. This stage usually begins between 2 and 10 years of age. The main characteristics in this stage are increased motor difficulties and seizures. However, you may notice improvement in your childs behavior. Once in the third stage your child may start to show more interest in her surroundings as well as an increase in her alertness and attention span. Her ability to communicate may improve as well. Some girls actually stay in this stage for most of their lives. The fourth stage is known as the late motor deterioration stage. This stage can also last for years even decades. The main characteristics of this stage include the development of scoliosis with increase muscle weakness, rigidity and spasticity as well as increased muscle tone causing abnormal posturing of parts of her upper body as well as her arms and legs.
Treating Rett syndrome requires a multi disciplinary approach including standard medical care in addition to physical, speech and occupational therapies. Then as your child gets older social and academic as well as job training services. Though there are no medications that can cure Rett syndrome there are some that can help manage certain symptoms like seizures and muscle stiffness. Rett syndrome is also one of those conditions in which proper nutrition is extremely important not only for normal growth but for improved mental and social skills. Some girls with Rett syndrome require a well balanced high calorie diet while others may need to be fed through a tube.
Most girls with Rett syndrome are able to survive into middle age and beyond despite the symptoms and difficulties associated with the condition.