Rett Syndrome 👧🧠:
A rare neurodevelopmental disorder caused by mutations in the MECP2 gene on the X chromosome.
Development is normal for the first 6–18 months, followed by regression in motor, speech, and cognitive skills, alongside stereotypic hand movements and seizures.
About ℹ️
- Genetics: Sporadic disorder due to a de novo mutation in the MECP2 gene (X chromosome).
- Incidence: ~1 in 8,500 females. Embryonically lethal in most males, but rare male cases occur.
- Primarily affects grey matter development and function in the brain.
Aetiology 🧬
- MECP2 gene mutation: Regulates transcription of multiple genes essential for neuronal growth and synaptic plasticity.
Clinical Features 👩⚕️
- Normal early milestones → regression at 6–18 months.
- Motor regression: Loss of purposeful hand skills, ataxia, hypotonia, choreiform movements.
- Cognitive/Language regression: Severe loss of verbal communication, learning disability.
- Behavioural: Autistic-like features, irritability, episodes of screaming.
- Characteristic hand-wringing 👐: Stereotypic midline movements.
- Systemic features: Seizures, arrhythmias (palpitations/syncope), GORD, scoliosis, osteoporosis.
Stages of Rett Syndrome 📊
- Early onset (≤18 months): Hypotonia, feeding difficulties, delayed sitting/crawling, loss of interest in toys.
- Regression (1–4 yrs): Severe language & motor loss, autistic-like withdrawal, stereotypic hand movements, breathing irregularities, irritability.
- Plateau (preschool to school age): Seizures, abnormal breathing (apnoea/hyperventilation), arrhythmias, bruxism, sleep problems. Social interaction may stabilise.
- Late deterioration (childhood → adulthood): Loss of ambulation, scoliosis, spasticity, profound motor decline. Seizures may reduce with age.
Investigations 🔍
- Genetic testing: Confirms MECP2 mutation.
- Neuroimaging (CT/MRI): May show cortical and subcortical changes but mainly used to exclude other causes.
Management 💊🤝
- Supportive therapy: No cure; focus on maximising quality of life.
- Anticonvulsants: Seizure control (e.g., valproate, levetiracetam).
- Multidisciplinary input:
- Physiotherapy (mobility, scoliosis prevention).
- Speech therapy (communication aids).
- Dietetic support for feeding/swallowing difficulties.
- Monitoring: Regular checks for scoliosis, arrhythmias (ECG), bone health, nutritional status.
- Psychosocial support: Family counselling and long-term care planning.
References 📚
💡 Exam Pearl
Key clue: A previously healthy girl (6–18 months) who regresses, loses language, and develops stereotypic hand-wringing = think Rett Syndrome.
Differentiates from autism (which lacks progressive neurological decline).
