Rett Syndrome, one of the MECP2 gene-related disorders, is a progressive neurologic disease in girls characterized by normal birth and apparently normal psychomotor development during the first six to 18 months of life.
Alternate Names: MECP2 Related Disorder, RTT, RTS
The girls enter a short period of developmental stagnation followed by rapid regression in language and motor skills.
The hallmark of the disease is the loss of purposeful hand use and its replacement with repetitive stereotyped hand movements. Screaming fits and inconsolable crying are common by age 18-24 months.
Additional characteristics include autistic features, panic-like attacks bruxism, (teeth grinding), episodic apnea and/or hyperpnea, gait ataxia and apraxia, tremors, and acquired microcephaly. After this period of rapid deterioration, the disease becomes relatively stable, though girls will likely develop dystonia and foot and hand deformities as they grow older.
Seizures occur in up to 90% of affected females.
Females with classic Rett syndrome typically survive into adulthood, but the incidence of sudden, unexplained death (which may be caused by cardiac arrhythmias) is significantly higher than in controls of similar age.
The diagnosis of Rett syndrome rests on clinical diagnostic criteria established for the syndrome and/or molecular testing of the MECP2 gene. Molecular genetic testing identifies MECP2 mutations in approximately 80% of females with Rett syndrome.
Currently there is no cure for RTT. Management is mainly symptomatic focusing on optimizing the individual's abilities and providing psychosocial support for the family.
Females with Rett syndrome may survive into adulthood, but in a very dependent state.
The incidence of sudden, unexplained death is significantly higher than in controls of similar age and may in part be caused by the higher incidence of longer corrected QT intervals, T-wave abnormalities, and reduced heart rate variability.