Autistic regression in relation to limbic pathology and epilepsy: report of two cases.

The authors report a follow-up study of two boys who presented with autistic regression (after normal early development) at 13 and 22 months. Both were found on cerebral imaging to have tuberous sclerosis, with lesions involving the limbic system, bilaterally in the second child. The first child's regression coincided with the onset of partial complex seizures; disappearance of the autistic behaviour and marked improvement in cognitive development occurred with remission of the epilepsy. The second child, who had probable seizures and a late-appearing epileptic focus on EEG, remained severely disabled. The autistic behaviour appears to be linked to pathology in the limbic system and a direct role of epilepsy in the regression is proposed.