Imagine the symptoms of autism, cerebral palsy, Parkinson's, epilepsy, and anxiety disorders ... all in one little girl!
Rett syndrome is a neurodevelopmental disorder. It was first reported in 1966 by Andreas Rett, an Austrian paediatric neurologist. Rett syndrome is a rare but severe brain disorder that affects only about one in 12,000 affects girls almost exclusively.
It is important to realise that though girls and women affected by Rett syndrome may have difficulty communicating verbally and physically, they experience a full range of emotions and understand more than they can express. They have engaging personalities and will enjoy taking part in social, educational and recreational activities at home and in the community.
Rett syndrome was at one time included under the autism umbrella, however a genetic cause for Rett syndrome (a mutation) was discovered, so it was reclassified as a neurologic disorder with a known genetic cause. This cause is a mutation in the MECP2 gene on the X chromosome. However, there is still much to be learnt about the disorder. Only in a very few cases (about 1%) is it inherited from the parents. Approximately 90–95% of Rett syndrome cases are caused by identifiable mutations of the MECP2 gene. More than 200 different mutations have been identified. In 99% of cases, these mutations occur sporadically and are not possessed or transmitted by a child’s parents (de novo mutations). Therefore, in the vast majority of cases Rett syndrome is not an inherited disorder. The chance of recurrence in subsequent children for parents who have one affected child is approximately 1%.
Babies with Rett syndrome are generally born after a normal pregnancy and delivery. In most cases of Rett syndrome, the child develops normally in early life. Between 6 and 18 months of age, though, changes in the normal patterns of mental and social development begin, which can be misdiagnosed as autism or cerebral palsy. The symptoms, progression, and severity of Rett syndrome can vary dramatically from one person to another. Rett syndrome is the second most common cause of severe intellectual disability after Down syndrome.
Photos courtesy of Grace Forrett.
Diagnosing Rett syndrome
The severity of the syndrome is hard to predict and can vary greatly, from being very debilitating to fairly mild, allowing much independence. The symptoms that may arise and their severity also vary and may change over time. Not all people will show the same symptoms and they may have different effects.
The characteristic symptoms of Rett syndrome are:
- slowing in growth of head circumference
- repetitive hand motions such as hand wringing, hand washing, clapping or hand mouthing
- social withdrawal, communication difficulties and cognitive impairment
Other symptoms include:
- loss of muscular coordination, particularly purposeful hand use
- delayed or absent ability to walk
- difficulty in breathing
- poor circulation leading to cold hands and feet
- disrupted sleep
- bending of the spine (scoliosis)
A fuller list of symptoms is given here:
- apparently normal prenatal and perinatal history
- psychomotor development largely normal through the first six months or may be delayed from birth
- normal head circumference at birth
- postnatal deceleration of head growth in the majority
- loss of achieved purposeful hand skill between ages ½–2½ years
- stereotypic hand movements such as hand wringing/squeezing, clapping/tapping, mouthing and washing/rubbing automatisms
- emerging social withdrawal, communication dysfunction, loss of learned words, and cognitive impairment
- impaired (dyspraxic) or failing locomotion
- awake disturbances of breathing (hyperventilation, breath holding, forced expulsion of air or saliva, air swallowing)
- impaired sleep pattern from early infancy
- abnormal muscle tone successively associated with muscle wasting and dystonia
- peripheral vasomotor disturbances
- scoliosis/kyphosis progressing through childhood
- growth retardation
- hypotrophic small and cold feet; small, thin hands
Stages of Rett syndrome
Stage 1 – 6 to 18 months
In this stage the first signs of the syndrome may become apparent.
May show a lack of interest in toys. May be calm and placid.
Development of motor skills may be slow. Head growth may slow.
Stage 2 – 1 to 4 years
In this stage, the greatest changes occurs, often rapid, though it may also be gradual.
May show lack of interest in social interaction and development of communication skills may be poor. May be quite irritable.
Repetitive hand motions may become apparent and purposeful hand skills may be lost.
Growth of head circumference may be slow.
Breathing problems may arise.
Stage 3 – 2 to 10 years
In this stage, the rapid regression of stage 2 will slow and improvements may be seen in behaviour, particularly in irritability. Should show more alertness and be communicative.
Motor control may still deteriorate. Loss of muscle tone may become apparent. May start having seizures.
Stage 4 – 10+ years (though very variable, may occur anywhere from about 5 to 25 years)
This stage is characterised by loss of mobility. The ability to walk may be lost, if it had been acquired. Stiffness and curving of the spine (scoliosis) may occur.
Communication abilities and cognition should not decrease however and repetitive hand motions may decrease.
Stages of Rett Syndrome in Girls courtesy of www.dealwithautism.com
To find out more about Rett syndrome visit Rett New Zealand