Rett syndrome is a unique postnatal neurological disorder that can be diagnosed in infancy and occurs almost exclusively in girls. Very rarely, it can be seen in boys.
Rett syndrome has often been misdiagnosed as autism, cerebral palsy, or a nonspecific developmental delay.
Rett syndrome is caused by mutations in a gene called MECP2, located on the X chromosome. More than 200 different MECP2 mutations have been identified, most of which cluster in eight recognized “hot spot” regions.
Rett syndrome occurs across all racial and ethnic groups and affects approximately one in every 10,000 female births worldwide. Its occurrence is entirely sporadic; parents are not carriers of Rett syndrome.
Rett syndrome is a postnatal neurological disorder and is not a degenerative disease.
Rett syndrome affects brain function related to cognition, sensory processing, emotion, motor skills, and autonomic regulation. As a result, individuals may experience challenges with learning, communication, sensory perception, mood, movement, breathing, heart function, and even chewing, swallowing, and digestion.
Symptoms typically emerge between six and eighteen months of age, following a period of apparently normal or near-normal early development during which acquired skills begin to slow or plateau. A regression phase follows, marked by loss of communication abilities and diminished purposeful hand use. Stereotypic hand movements resembling hand-wringing, gait abnormalities, and slowed head growth may also appear. Additional issues can include seizures and irregular breathing while awake. In the early stages, periods of irritability, restlessness, or withdrawal may occur when the child is distressed or crying. Over time, motor difficulties may increase, but irritability generally lessens, and eye contact and communication tend to improve.
Rett syndrome is confirmed through a simple blood test that identifies an MECP2 mutation. However, because MECP2 mutations can appear in other conditions as well, the presence of a mutation alone is not sufficient for diagnosis. Diagnosis requires either identification of the mutation (molecular diagnosis), meeting the diagnostic criteria based on observable signs and symptoms (clinical diagnosis), or both.
Rett syndrome can present with a wide range of severity, from mild to severe. Its course and severity are influenced by the mutation type, mutation site, and X-chromosome inactivation. For this reason, two girls with the same mutation and the same age may appear quite different.
Although Rett syndrome brings many challenges, with love, intensive therapy, and appropriate support, individuals with Rett syndrome can benefit from school and community activities well into adulthood and beyond.
Source: International Rett Syndrome Association – www.rettsyndrome.org