Rett's Syndrome
Thaweesak Siriratrekha, MD, Child and Teenager Psychiatrist
Rett's Syndrome is classified in a group of PDDs (PDDs - Pervasive Developmental Disorders). Most patients are woman. Approximately 1 patient is found in 10,000-15,000 first-born babies. Abnormalities cannot be examined during prenatal period. At first birth a heads diameter is normal. Muscular and motive developments are also normal but after 5 months, some abnormalities are present. The growth of head is slow (often found during 5 months to 4 years of age), loss of hand skills, loss of purposeful hand movements (frequently found during 6-30 months), followed by repeated and irregular hand movements around the chest, for example, twisting hands back and forth or acting like washing hands, having gait ataxia and truncal ataxia/ apraxia, staggering and eventually getting unable to walk.
There are disabilities in language development both receptive and expressive aspects but a child still needs to communicate through eye contact to show interests or wants (eye pointing). Social development, social interactions and play will cease in the first period but can be developed later on. A child yet shows his interests in surrounding movements. The intellectual disabilities at a severe stage are also investigated. Some have seizures while someone has muscular contractions, crooked bone and physical growth is rather slow.
Rett's Syndrome is the most genetic related among PDDs because the position of genes involved is explicitly identified which is MeC-P2 in chromosome X at Xq28. It is indicated that 50 percent of women meeting diagnostic criteria showed the mutation of MeC-P2 leading to brain dysfunctions and more severe symptoms. (Progressive X-linked dominant encephalopathy)
