Rett Syndrome

Overview

Rett syndrome is a rare neurological disorder that primarily affects girls, occurring in approximately 1 in 10,000 to 15,000 live female births. It was first described by Austrian pediatrician Andreas Rett in 1966. The condition is characterized by a period of normal development followed by a loss of acquired skills, such as purposeful hand skills and spoken language. Rett syndrome is considered a spectrum disorder, meaning that its severity can vary widely among individuals.

Symptoms

The symptoms of Rett syndrome can be categorized into several stages. In the early stages, affected individuals may show normal development, but between six months and two years of age, a period of regression occurs. This regression is marked by the loss of purposeful hand skills, such as the ability to grasp objects, as well as a decline in social engagement and communication skills.

Other symptoms may include repetitive hand movements, such as wringing or clapping, and the development of characteristic hand-washing movements. Individuals with Rett syndrome often experience motor difficulties, including problems with coordination and balance. Breathing irregularities, such as hyperventilation and breath-holding, are common. Additionally, there may be a loss of purposeful communication skills, with some individuals becoming nonverbal.

Causes

Rett syndrome is primarily caused by mutations in the MECP2 gene, which is located on the X chromosome. Most cases of Rett syndrome are sporadic, meaning they occur by chance and are not inherited. The majority of individuals with Rett syndrome have mutations in the MECP2 gene that are not inherited from their parents but arise spontaneously. In some cases, the mutation can be inherited from a parent who carries a genetic change in the MECP2 gene.

Although the exact function of the MECP2 gene is not fully understood, it plays a crucial role in the normal development and function of the nervous system. Mutations in this gene disrupt the normal functioning of neurons, leading to the neurological features observed in Rett syndrome.

Types

Rett syndrome is typically classified into several subtypes based on genetic and clinical features. The most common subtype is classic Rett syndrome, which accounts for the majority of cases. In addition to classic Rett syndrome, atypical variants have been identified, including preserved speech variant, congenital variant, and Zappella variant.

The preserved speech variant is characterized by the presence of some language abilities, distinguishing it from classic Rett syndrome. Congenital variants are evident from birth, and individuals with this subtype may not show the period of typical development seen in classic Rett syndrome. The Zappella variant is associated with a milder course of the disorder and a later onset of symptoms.

Diagnosis

Diagnosing Rett syndrome involves a clinical evaluation of the individual's symptoms and developmental history. The key criteria for diagnosis include a period of regression, loss of purposeful hand skills, and the development of characteristic hand movements. Additionally, mutations in the MECP2 gene can be identified through genetic testing, which supports the clinical diagnosis.

It is essential to consider other conditions with similar symptoms during the diagnostic process. Differential diagnosis may include other neurodevelopmental disorders, metabolic disorders, and genetic syndromes.

Treatment & Management

Currently, there is no cure for Rett syndrome, and treatment focuses on managing symptoms and providing supportive care. A multidisciplinary approach involving various healthcare professionals, such as neurologists, physical therapists, speech therapists, and occupational therapists, is typically employed to address the diverse needs of individuals with Rett syndrome.

Therapeutic interventions may include physical therapy to improve motor skills, occupational therapy to enhance daily living activities, and speech therapy to address communication challenges. Medications may be prescribed to manage specific symptoms, such as seizures and breathing irregularities.

Supportive care is crucial in maintaining the overall well-being of individuals with Rett syndrome. This may involve assistance with activities of daily living, the use of adaptive equipment, and creating a supportive environment to enhance the individual's quality of life.