Two sisters with Rett syndrome.

We present the clinical histories and physical findings of two sisters with Rett syndrome. The physical examination, combined with a review of their medical charts, revealed that both patients met the necessary criteria for the diagnosis of Rett syndrome as defined by the Rett syndrome diagnostic criteria work group. The older sister, currently 25 years of age, is typically affected, whereas the younger sister, currently 22 years of age, is affected with a seizure disorder showing an unusually early onset.