Diagnostic Parameter, Rett's Disorder

Rett's Disorder

An inherited disorder that affects only females, the syndrome causes mental retardation and developmental degeneration. The following suggest normal early development:

Prenatal and perinatal development appear normal.

Psychomotor development appears normal at least until month 6 old.

Head circumference is normal at birth.

After this period of normal development, all of:

Head growth slows abnormally between 5 and 48 months.

Between 5 and 30 months, the child loses already acquired purposeful hand movements and develops stereotyped hand movements such as handwashing or handwringing.

Early in the course, the child loses interest in the social environment. However, social interaction often develops later.

Gait or movements of trunk are poorly coordinated.

Severe psychomotor retardation and impairment of expressive and receptive language.