Article title
Fehr, S, Downs, J, Bebbington, A & Leonard, H 2010, 'Atypical presentations and specific genotypes are associated with a delay in diagnosis in females with Rett syndrome', American Journal of Medical Genetics Part A, vol. 152A, pp. 2535-2542. Download snapshot, see article abstract.
Background
There is often a delay between the time when the symptoms of Rett syndrome first appear and when a diagnosis of Rett syndrome is made. We investigated the factors that may affect the age at diagnosis for girls and woman with Rett syndrome.
What we did
Using information from 909 families participating in the Australian Rett Syndrome Study and InterRett, we investigated whether the age of the child's diagnosis was related to the familiy's socioeconomic status, the child's birth order, mother's age and the age when typical Rett syndrome features first appear.
What we found
We found that girls who develop symptoms that are typical of Rett syndrome were diagnosed at an earlier age. Therefore those who lost hand function or communication skills later or who developed hand stereotypies at an older age were diagnosed later. Girls with the p.R133C or p.R294X MECP2 mutations also tended to have a later age of diagnosis. The families' socioeconomic status was not related to the age at diagnosis for Australian families. However for families participating in the InterRett database, a younger age of diagnosis was associated with higher levels of parental education or occupation.
What does it mean
There is a broader range of symptoms in Rett syndrome then just those which follow the classical picture. These include the milder, less typical presentations which sometimes involve a delayed onset of regression or a delayed occurrence of hand stereotypies. It is important that clinicians are aware of these presentations so that diagnoses are not missed as has previously occurred. We need to make sure that doctors are aware of the full extent of the clinical variability of presentations in Rett syndrome.