Rett syndrome.

Rett syndrome is a rare, progressive, neurodevelopmental disorder that has been reported only in the girl child. We describe the case of a 6.9-year-old girl with Rett syndrome. She had normal development till the age of 2 years. However, over the next 4-5 months, she lost her acquired, purposeful hand skills; expressive and receptive language; and reciprocal social interaction; and gradually developed a broad-based gait and typical midline stereotyped hand movements (mouthing, rubbing).