Landau‐Kleffner Syndrome: A Clinical and EEG Study of Five Cases

Abstract

In five children with normal initial psychomotor development, a Landau-Kleffner syndrome appeared at age 3-7 years. No neuroanatomic lesions were noted. Aphasia and hyperkinesia were isolated in three patients and associated with global regression of higher cortical functions in one patient. Massive intellectual deterioration and psychotic behavior were associated with transient aphasia in one patient. The epilepsy (focal motor and generalized tonic-clonic seizures, subclinical EEG focal seizures during sleep, and atypical absences) always regressed spontaneously or with antiepileptic drug (AED) treatment. The EEG in waking patients showed focal and generalized spike-wave discharges on a normal background rhythm. Discharge topography and pattern changed frequently. During sleep, discharges always increased. At some time during syndrome development, all patients had bilateral spike-waves for greater than 85% of the sleep period, while at other times the discharges were discontinuous or continuous but focal or unilaterally hemispheric. Discharge topography and abundance changed from night to night. The abnormal EEG and the impaired higher functions developed and regressed together, but not with strict temporal correlation. Our own experience suggests that the Landau-Kleffner syndrome and epilepsy with continuous spike-wave activity in slow-wave sleep cannot be clearly differentiated. They may be different points on the spectrum of a single syndrome.

Landau kleffner syndrome, electrical status epilepticus in sleep and autistic regression: an overview of literature / Landau kleffner sendromu, uykuda elektriksel status epileptikus ve otistik regresyon: Literatüre bir bakış

“…In LKS, structural brain abnormality is uncommon. Both computed tomography and MRI are usually normal (13,(18)(19)(20)(21)(22).…”

“…Lagae (26), in his recent review indicated the use of antiepileptic drugs (AEDs) as the first-line treatment, including VPA and ethosuximide. However, a number of reports have shown that the early use of steroids, including prednisone, methylprednisolone and/or andrenocorticotropic hormone (ACTH) are effective in improving both the EEG abnormality and language (18,(27)(28)(29)(30)(31). Series published to date used very different schemes of steroid treatment, different dosing and time course, making comparisons difficult.…”

The electrophysiological “delayed effect” of focal interictal epileptiform discharges. A low resolution electromagnetic tomography (LORETA) study

“…However, other investigators described fluctuating neurological symptoms, disturbed speech and cognitive impairment that were related to the presence of frequent IEDs but not strictly time-locked to them. Drug treatment that abolished the spikes caused significant clinical improvement within a short time period (Hirsch et al, 1990;Metz-Lutz et al, 1999;Baglietto et al, 2001;Massa et al, 2001;Dalla Bernardina et al, 2002). Thus, a "delayed effect" of the IEDs might be deductively postulated as an explanation for the lack of the precise temporal coincidence between the IEDs and the time course of the above mentioned symptoms.…”

A Review of the Not So Benign- Benign Childhood Epilepsy with Centrotemporal Spikes

“…Similarly in other recent studies despite promising logarithm of odds (LOD) scores, no genetic mutations have been identified [31,32]. Recent studies in some families has shown an overlap between epileptic encephalopathy with CSWS, atypical benign partial epilepsy, and BECTS which has led to the concept of a spectrum of epilepsy-aphasia disorders with BECTS at the lower end, the broad less well-defined group of epilepsy-aphasia children in the middle, and classical LKS and the syndrome of CSWS at the extreme end [30,[33][34][35]. This overlap suggests an additional genetic as well as environmental factors which determine whether the spectrum of disease will manifest as BECTS or as epileptic-aphasia spectrum disorder.…”