Evolution of stereotypies in adolescents and women with Rett syndrome.

Stereotypies in Rett syndrome (RTT) are a diagnostic hallmark present in all stages of the disease, but descriptions of movement disorders in adults are very scant. Among 30 patients with RTT followed-up at San Paolo Hospital in Milan, we selected those aged > or =14 years and studied 12 patients (mean age 18. 6 years, range: 14-31) with MECP2 mutations. Mean age at stereotypies onset was 19.4 months; stereotypies at onset tend to be maintained during evolution, while new stereotyped movements can be detected in the follow-up. All patients still present stereotypies involving separated or joined hands: most frequently mouthing, pill rolling, and twisting. We underline that stereotyped movements persist in older patients and can be useful to suspect RTT diagnosis in adult age in otherwise unclassified patients.