Autism Studies and Related Medical Conditions, January 2009 - TACA

significantly more frequent in patients with epilepsy than in non-epileptic patients (p =
0.003). Abnormal development during the first year of life was significantly associated
with epileptiform EEG abnormalities (p = 0.014). Epilepsy correlated significantly with
mental retardation (p = 0.001). Although the biological basis and possible causal
relationships of these associations remain to be explained, they may point to different
subgroups of patients with autistic spectrum disorders.
244. McVicar KA, Shinnar S. Landau-Kleffner syndrome, electrical status epilepticus in
slow wave sleep, and language regression in children. Ment Retard Dev Disabil Res Rev.
2004;10(2):144-9. PMID: 15362173
The Landau-Kleffner syndrome (LKS) and electrical status epilepticus in slow wave sleep
(ESES) are rare childhood-onset epileptic encephalopathies in which loss of language
skills occurs in the context of an epileptiform EEG activated in sleep. Although in LKS
the loss of function is limited to language, in ESES there is a wider spectrum of
cognitive impairment. The two syndromes are distinct but have some overlap. The
relationship between the epileptiform EEG abnormalities and the loss of cognitive
function remains controversial, even in LKS which is the most widely accepted as an
acquired epileptic aphasia. Language regression also occurs in younger children,
frequently in the context of a more global autistic regression. Many of these children
have epileptiform EEGs. The term autistic regression with epileptiform EEG has been
proposed for these children. Whether these children are part of an extended LKS
spectrum is very controversial, because there are differences in age of onset, clinical
phenotype, and EEG findings. An understanding of the available data on clinical
characteristics, EEG findings, pathology, prognosis, and treatment of these syndromes
is essential for further progress in this area.
245. Tharp BR. Epileptic encephalopathies and their relationship to developmental
disorders: Do spikes cause autism? Ment Retard Dev Disabil Res Rev. 2004;10(2):132-
4.
Epileptic encephalopathies are progressive clinical and electroencephalographic
syndromes where deterioration is thought to be caused by frequent seizures and
abundant EEG epileptiform activity. Seizures occur in approximately 10-15% of children
with pervasive developmental disorders (PDD) and 8-10% have epileptiform EEG
abnormalities without seizures. Thirty percent of children with PDD have regression of
social behavior and language at 2-3 years of age. Some authors speculate that the
regression is caused by epileptiform activity even in the absence of overt clinical
seizures ("autism with epileptic regression") and suggest that elimination of the
epileptiform activity, either medically or surgically, should lead to improvement in
behavior. This review examines the data showing that interictal epileptiform discharges
are associated with transient clinical dysfunction and discusses the implications of these
observations for autistic behavioral abnormalities. The results of resective surgery,
vagal nerve stimulation, and multiple subpial transaction on children with autism and
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