Epileptiform Activity in Aphasia of Childhood:An Epiphenomenon?

Abstract

Summary: Isolated aphasia with associated EEG epileptiform activity is a recognized syndrome in children. The relationship of the EEG abnormality and the type and severity of the speech impairment has not been well described. This relationship was studied in two children with severe expressive and receptive aphasia with generalized spike‐wave discharges on EEG using prolonged EEG FM radiotelemetry and video recording (TEEG‐VR). Speech was compared with 10 children with absence seizures with similar EEG abnormalities also evaluated using TEEG‐VR. In addition. 43 cases of aphasia with epileptiform activity on the EEG reported in the English literature were reviewed. Speech abnormalities in absence seizures consisted of speech arrest. decreased speed of speech, and brief periods of partial or complete receptive and expressive aphasia, always directly associated with a spike‐wave ictus. Speech abnormalities in acquired or congenital aphasia were not related to epileptiform activity and were characterized by severe articulation difficulties. syntactic transformation, paraphasia, and receptive and expressive aphasia. Anticonvulsants did not alter speech. Based on these two cases and the 43 others reviewed in the literature, it is proposed that epileptiform activity in this syndrome is an epiphenomenon reflecting underlying abnormalities of speech areas rather than the cause of the aphasia. RÉSUMÉ Une aphasie isolée, associée à une activité EEG épileptiforme constitue un syndrome reconnu en pédiatric Mais les relations qui existent entre les anomalies EEG et le type ou la sévérité des troubles du langage n'ont pas été bien définies. Nous avons étudié ces relations chez deux enfants présentant une aphasie d'expression et de réception sévère et des décharges de pointe‐ondes généralisées; ils ont été enregistrés en télémfrie et en vidéo (TEEG‐VR) leur langage a été compareéà celui de dix enfants étudiees eux aussi en TEEG‐VR présentant des absences associées aux memes anomalies EEG. De plus ont été passés en revue 43 cas d'aphasie avec EEG épileptiforme publies dans la litterature de langue anglaise. Les troubles du langage pendant les absences consistent en arret du langage. ralentissement du débit verbal et bréves périodes d'aphasie de réception et d'expression, partielle ou compléte, directement associées aux decharges de pointe‐ondes. Les troubles du langage dans les aphasies acquises ou congenitales ne sont en rien relies aux decharges épileptiformes et sont caractérisés par d'importantes difficultes d'articulation, de transformation syntactique. de paraphasie et d'aphasie de réception ou d'expression. Les médicaments antiépileptiques n'altérent pas le langage. En se basant sur leurs deux cas et sur 43 cas de la littérature, les auteurs proposent que I'activitéépileptifome dans le syndrome en question soit considérée comme un épiphénomène témoignant d'anomalies au niveau de la zone du langage plutôt que comme la cause de L'aphasie. ZUSAMMENFASSUNG Die isolierte Aphasie mit begleitender epileptiformer EEG‐Aktivitat is...

Regional Cerebral Blood-Flow with 99mTc-ECD Brain Perfusion SPECT in Landau-Kleffner Syndrome: Report of Two Cases

“…Discussion about the correlation or incoherence of aphasia and epilepsy with an abnormal perfusion area in is not lacking. Holmes et al believed that abnormal cerebral perfusion in the temporal lobe independently caused both seizures and language disorders in LKS [8]. Rintahaka et al, by PET scan, showed that LKS is a generalized cerebral disease with a focal lesion that predominantly involves the perisylvian area [7], although they did address the generalized histological examination of patients affected by LKS.…”

Neurophysiology of Language and Behavioral Disorders in Children

“…However, the severity of the aphasia does not always have a close correlation with degree of EEG abnormality 107,119 or the severity of clinical seizures. Speech usually does not improve in the syndrome unless the EEG improves.…”

“…Speech usually does not improve in the syndrome unless the EEG improves. 107,120,121 Even if the EEG parallels speech recovery, this does not prove that epileptiform activity causes aphasia. 101 It is possible that the epileptiform activity is an epiphenomenon and simply is reflective of an underlying cortical abnormality.…”

“…Landau and Kleffner 101 made the association of language disturbance with seizures. [106][107][108][109][110] Children with Landau-Kleffner syndrome have a severe receptive and expressive aphasia, with a more severe disturbance of language reception. The EEGs of these children showed bitemporal spike discharges, though other electrographic patterns (focal temporal spikes, multifocal slow spikes, slow spike bursts, slow spike-wave complexes maximal posteriorly, electrical status epilepticus in sleep) have since been reported in association with the characteristic language disorder (Fig.…”

What is more harmful, seizures or epileptic EEG abnormalities? Is there any clinical data?

“…Speech deficits in the syndrome may be explained by either disruption of normal connections or an excessive inhibitory reaction to epileptiform discharges. However, the severity of the aphasia does not always have a close correlation with degree of EEG abnormality (Foerster, ; Holmes et al ., ) or clinical seizures (Landau and Kleffner, ). It has been suggested that the epileptiform activity is an epiphenomenon and simply is reflective of an underlying cortical abnormality (Lou et al ., ; Kellermann, ; Holmes et al ., ).…”