Rett Syndrome

Rett syndrome is a severe genetic neurodevelopmental disorder that affects the ability to speak, walk, and breathe. In short, it impacts all aspects of life. Considered a rare disease, it primarily affects women since it is usually fatal for men.

The development of babies with Rett syndrome is normal, or seemingly normal, during their first six months. After that, not only does progress stop, but previously acquired skills are lost. Its most distinguishing characteristic is the constant and repetitive movement of the hands.

Rett syndrome progresses in four stages:

• Early onset: Development halts or slows down to the point of being imperceptible. It is common for babies to have trouble crawling or show little interest in the objects around them. This phase usually occurs between 6 and 18 months.
• Rapid deterioration: Children between one and four years old lose the skills they had initially gained and begin to show the first symptoms of the syndrome, such as movement disturbances.
• Stabilization: Between 2 and 10 years old, the disease’s progression slows, and behavior improves along with reduced irritability. However, movement problems persist, and seizures may begin to appear.
• Late motor deterioration: From age 10 onward, mobility decreases due to muscle weakness, joint stiffness, and, in many cases, scoliosis. Seizures tend to disappear, and communication, comprehension, and hand use improve.

Neurologist Andreas Rett first described this syndrome in 1966, but it wasn’t until 1999 that a team led by Huda Zoghbi identified it as being caused by a mutation in the MECP2 gene, located on the X chromosome and involved in neuronal development and maturation. Adrian Bird’s research in 2007 demonstrated that Rett syndrome can be reversed if this gene’s function is restored, but a method to apply this treatment to humans has not yet been found. Therefore, currently, only some symptoms can be alleviated or minimized.

It is common for patients with Rett syndrome to reach adulthood, although their life expectancy is lower than average.

Symptoms

The symptoms of Rett syndrome can vary slightly in the different stages of the disease. The most notable include:

• Repetitive and abnormal hand movements.
• Delay in head growth.
• Movement, coordination, and balance issues, leading to an inability to walk.
• Hyperventilation.
• Apnea.
• Irritability.
• Screaming.
• Lack of social interaction.
• Loss of communication abilities.
• Seizures.
• Altered eye movements.
• Intellectual disability.
• Scoliosis.
• Irregular heartbeat.

Causes

Rett syndrome is caused by a mutation in the MECP2 gene, although the reason for this mutation is unknown. In some cases, patients show symptoms similar to those of the disease but do not meet all diagnostic criteria, in which case they are diagnosed with atypical Rett syndrome.

Atypical forms of Rett syndrome are associated with alterations in other genes, especially CDKL5 and FOXG1.

Risk Factors

The mutation that causes Rett syndrome is random, meaning there are no known factors that increase the risk of developing it, not even hereditary ones, as only 1% of cases are passed down from generation to generation.

Complications

It is common for individuals with Rett syndrome to experience other conditions, such as:

• Epilepsy.
• Sleep disturbances.
• Behavioral disorders.
• Dysphagia: difficulty swallowing.
• Constipation.
• Anxiety.
• Misbehavior.
• Bruxism: teeth clenching or grinding.
• Malocclusion: improper alignment of the teeth.

Prevention

Since it is a genetic mutation, Rett syndrome cannot be prevented.

Which doctor treats Rett syndrome?

Rett syndrome is diagnosed in the pediatric neurology unit. Afterward, treatment is addressed by various specialties such as physical medicine and rehabilitation, speech therapy, or child psychology.