Rett syndrome is a sporadic pervasive developmental disorder which is observed almost exclusively in females. (1,2)
The prognosis is poor, with symptomatic relief being the only treatment option.
Rett syndrome (RS) is a neurodevelopmental syndrome affecting almost exclusively female children and first appearing at 7–18 months
- prior to the onset of symptoms, development appears normal
- after symptomatic onset patient development deteriorates rapidly and severe dementia, autism and other features develop
- the locus for inheritance of this condition is Xq28
- RS results from mutations in the in the methyl-CpG-binding protein-2 gene (MECP2)
- inherited as an X-linked dominant
- most cases are sporadic; de novo mutations occur almost exclusively on the paternally derived X chromosome
- prevalence 1 in 10,000 to 1 in 15,000 female births
- is not a neurodegenerative condition, rather it is a progressive disorder involving multisystem symptom evolution over time
- 70% of patients with RS live to at least 50 years of age
- features associated with RS include:
- short stature
- cachexia
- head circumference is normal at birth but there is deceleration of head growth
- growth of the head decelerates between six months and four years and consequent microcephaly
- bruxism of the teeth
- cardiological features include prolonged QTc interval and T-wave abnormalities
- respiratory features include
- periodic apnoea whilst awake
- breath holding
- intermittent hyperventilation
- abdominal features include
- constipation
- gastroesophageal reflux
- skeletal abnormalities include scoliosis; kyphosis
- patients have small and cold feet
- neurological features
- development is normal until until 6-18 months
- subsequent development of mental retardation, spasticity
- seizures develop in up to 75%
- behavioural/psychiatric manifestations include
- autistic behaviours
- hand stereotypies - often clasped together, with wringing movements and clapping
- sleep disturbance
- bruxism
- breath holding
Notes:
* there have been rare reports of Rett syndrome in males
Reference
- Asuncion R et al. Rett Syndrome. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Mar.
- Fu C et al. Consensus guidelines on managing Rett syndrome across the lifespan. BMJ Paediatr Open. 2020 Sep 13;4(1):e000717.