Autism and tuberous sclerosis complex: prevalence and clinical features.

This study employed a hierarchical assessment to detect the prevalence of autism in a clinic sample of individuals with tuberous sclerosis complex (TSC). After screening subjects with the Autism Behavior Checklist, subsequent evaluations with the Autism Diagnostic Interview, and direct clinical observation, the prevalence of autistic disorder in this sample of 20 subjects was conservatively estimated at 20%. Data suggest a possible association between both hypsarrythmia and TSC-related cardiac abnormalities with autism in this subgroup of TSC individuals. Implications of these findings for clinical practice and further research are discussed.