Hello friends!
Today we are going to learn about Rett syndrome.
*Frequency : 1 in 15,000.
*90% of the cases are SPORADIC
*5-10% are X-Linked Dominant, so more common in females.
(Remember males get only one X chromosome from mother whereas females get X chromosome each from mother and father).
*Mutation in gene : MeCP2.
*Virtually always seen in girls because males usually die in utero or shortly after birth.
*Important finding : Decreased pontine NE and Nigro-striatal Dopamine levels.
Clinical features :
*At birth : Normal growth and normal head circumference.
*Normal attainment of milestones till 5-6 months of age, later there will be progressive regression of language (both receptive and expressive) and motor milestones.
*It causes Acquired Microcephaly.
*Hallmark : Repetitive hand writing movements with loss of purposeful movements.
*It can cause 5 As:
Apnea (intermittent)
Ataxia
Autistic behaviour
Arrhythmias
Acquired Microcephaly
*In addition to all of these, cyanosis, GTCS can also be seen.
*Staging :
Stage 1 : Onset stage (6-18 months)
Stage 2 : Rapid destructive (1-4 years) -
Stage 3 : Plateau phase (2-10 years)
Stage 4 : Late motor phase (decreased motor movts) - Scoliosis can occur.
*Imaging : No pathognomonic finding. However, significant reduction on brain weight upto 60-80% is often seen.
*HPE : Decreased synapses, dendritic length and branching.
*Treatment : Supportive.
Hope it will help :)
Madhuri.