Language and behavioral disturbances associated with epileptiform EEGs

The appearance of language or behavioral regression in previously normal children is a devastating experience for both the family and the patients. In some cases, evaluation with prolonged sleep electroencephalograms (EEGs) reveals a dramatic activation of epileptiform activities. These may be continuous and diffusely appearing spike-wave discharges in slow-wave sleep, also known as "electrical status epilepticus in sleep" (ESES), or they may be more focal but very frequent temporal, centrotemporal, or multifocal spikes. The typical syndromes are the encephalopathy associated with ESES or continuous spike waves during slow-wave sleep (CSWS) and Landau-Kleffner syndrome (LKS). A significant minority of children with pre-existing impairments in sociability, communication, and behavior, typical of autistic spectrum disorders, may manifest epileptiform abnormalities, which perhaps further exacerbate the language or neuropsychiatric dysfunction. Patients with autistic regression with epileptiform EEGs (AREE) may have clinical and electrographic similarities with CSWS or LKS children. In this review, we will summarize the existing knowledge about these syndromes and the existing therapeutic strategies. Awareness about these syndromes is of paramount importance in order to implement early detection and treatment, which may ameliorate the outcome.