Rare intellectual disability in baby girls – Rett Syndrome

Studies say 1 out of every 15000 infant girls are born develops Rett syndrome.

By Dr Sumit Singh, 

What is Rett Syndrome?

Rett syndrome is a rare but severe genetic neurological and developmental disorder that affects the development of the brain. This disorder is found exclusively in girls.

Rett syndrome inherits the ability to use muscles for eye and body movements and speech. It usually comes in the first two years of life. Most babies at around six months of age show normal signs of development but after that they lose skills they previously had — such as the ability to crawl, walk, communicate or use their hands.

This syndrome causes seizures and intellectual disability sometimes. Studies say 1 out of every 15000 infant girls are born develops Rett syndrome. If the first child has Rett syndrome, there is less than one percent chance of having the second child with this syndrome.

Symptoms

Babies with Rett syndrome are born with normal pregnancy and delivery. The symptoms, their severity and associated disability varies from babies to babies. Most babies with Rett syndrome grow and behave normally for the first six months. Mostly the chances occur at 12 to 18 months of age, it can be over a period of weeks or months.

Slow growth: The growth of the brain slows down. It also affects the size of the head. Babies with Rett syndrome have smaller heads in comparison to the normal size. The growth of the brain becomes stunted and it becomes clearer with the growing age of a child.

Body movement problems: The first signs with the children with Brett syndrome face reduced hand control and a decreasing ability to crawl or walk normally. When the symptoms start, his loss of abilities occurs rapidly and then it continues more gradually. The muscles become weak or may become rigid or spastic with abnormal movement and positioning.

Loss of communication abilities: The main age between 1-4 when the child learns to communicate, interact and socialise this syndrome begins to lose their ability to speak, to make eye contact and to communicate. Children become disinterested in other people, toys and their surroundings and can also have extreme social anxiety. Some even have sudden loss of speech. With the passing years some children also regain eye contact and develop nonverbal communication skills.

Abnormal hand movements: Child develops repetitive, purposeless hand movements. Hand movements may include hand wringing, squeezing, clapping, tapping or rubbing.

Unusual eye movements: Children tend to have unusual eye movements, such as intense staring, blinking, crossed eyes or closing one eye at a time.

Breathing problem: Child may have uncoordinated breathing, abnormally rapid breathing (hyperventilation),forceful exhalation of air or saliva, and swallowing air. These problems occur during waking hours but not during sleep.

As the child gets older they tend to become very agitated and irritable. They may cry or scream for long hours or even have long fits of laughter.
Some also experience seizures at some time during their lives.

Scoliosis also known as abnormal curvature of the spine is common with Rett syndrome. It begins at the age of 8 years and can increase with time. It can also lead to surgery if the curvature is severe.

The other symptoms like thin, fragile bones prone to fractures; small hands and feet that are usually cold; problems with chewing and swallowing; and teeth grinding. Symptoms vary from child to child.

When to see a Doctor?

Signs and symptoms are subtle in early stages. Parents should keep on monitoring the changes in physical and behavioural nature of the changes in comparison from the normal development before such as :

– Slow growth of child’s head
– Decreased coordination
– Repetitive hand movements and decreased eye contact.
– Loss of previously gained milestones and delayed speech development.

Prevention

There is no cure for Rett syndrome but there are treatments which focus on managing the symptoms. And if the girl continues with the therapy through her entire life it’s very much helpful and supportive for her.
Options include :

– Medications for breathing and anti-epileptic medicine to control seizures.
– Speech and language therapy
– Behavioural therapy
– Occupational therapy
– Hand splint to control hand movements
– High-calorie diet is given to maintain sufficient weight.
– Pace-maker to control heart rhythm.

Experts believe if these therapies are continued for a long time, it can help girls with Rett syndrome. They can go to school and learn better social interaction.

Why is Rett syndrome only found in females?

Females have two X chromosomes in every cell. Rett syndrome is caused by the mutation of the MECP2 gene. MECP2 is essential for the normal functioning of nerve cells. Also is likely to be involved in repressing the several other genes. MECP2 is a component of the X chromosome. Due to mutation, out of two X chromosomes that females have, only one remains active in each cell.

This means that females with Rett’s syndrome only use a portion as the other x chromosome is missing the functionality and hence it is impaired. But still, since the other X is fully functional, the core metabolic and neuro-functional requirements are still met and the girl survives.

What is the life expectancy of a person with Rett syndrome?

This syndrome gets worse till the teen years. But the symptoms may improve . The average life expectancy for girls may be mid-40s. Death is often related to seizure, aspiration pneumonia, malnutrition, and accidents.

(The author is Director, Neurology, Agrim institute of neuro sciences, Artemis Hospital. The article is for informational purposes only. Please consult medical experts and health professionals before starting any therapy, medication and/or remedy. Views expressed are personal and do not reflect the official position or policy of the Financial Express Online.)