Landau-Kleffner Syndrome: A Pharmacologic Study of Five Cases

Five children with Landau-Kleffner syndrome (epilepsy, acquired aphasia, and continuous spike-wave discharges during sleep), were treated with antiepileptic drugs (AEDs), sleep-modifying drugs, and corticosteroids. The pharmacologic profiles differed from those observed in focal epilepsies, resembling instead those of certain generalized epilepsies, such as West or Lennox-Gastaut syndromes. Phenobarbital (PB), carbamazepine (CBZ), and phenytoin (PHT) were ineffective or worsened the EEG and neuropsychological symptoms, whereas valproate (VPA), ethosuximide (ESM), and benzodiazepines were partially or transiently efficacious. Dextroamphetamine produced a dramatic but transient improvement in waking and sleep EEG in one of two children; aphasia did not change. Corticosteroid treatment resulted in improved speech, suppression of seizures, and normalization of the EEG in three of three children. Our own experience and data from the literature suggest that corticosteroids should be given in high doses as soon as the diagnosis is firmly established and should be continued in maintenance dose for several months or years to avoid escape. Early diagnosis, before mutism or global deterioration develops, appears to be essential for effective therapy with minimal neuropsychological sequelae.     

Cerebral Glucose Utilization During Sleep in Landau-Kleffner Syndrome: A PET Study

Three right-handed male children (aged 5, 6, and 11 years) with signs, symptoms and/or history of the syndrome of acquired aphasia-epilepsy (Landau-Kleffner syndrome) were studied during drug-induced, electroencephalographically (EEG)-monitored sleep by positron-emission tomography (PET) and the [18F]fluorodeoxyglucose (FDG) method. Our data demonstrate that in Landau-Kleffner syndrome, cerebral glucose utilization is not normal during sleep. The metabolic pattern varied between the children but the metabolic disturbances always predominated over the temporal lobes. They were right-sided, left-sided, or bilateral. In the two first patients, EEG recordings showed continuous spike-and-wave discharges during sleep and a right-greater-than-left asymmetry was observed in temporal areas. In patient 1, the asymmetry was associated with a relative increase of glucose utilization of the right posterior temporal region. In patient 2, the glucose utilization was relatively decreased in the left anterotemporal and left perisylvian regions. In patient 3, the sleep EEG showed no discharge and no significant asymmetry was observed; however, glucose utilization of both temporal lobes was decreased. Lower metabolic rates in subcortical structures than in cortex were also noted in the three children. This metabolic pattern may be related to the maturation of the central nervous system (CNS).     

EEG Abnormalities in Children with a First Unprovoked Seizure

Summary: We examined EEG findings from an ongoing study of 347 children with a first unprovoked seizure. EEGs were available in 321 (93%), and 135 (42%) had an abnormal EEG. EEG abnormalities included focal spikes (n = 77), generalized spike and wave discharges (n = 28), slowing (n = 43), and nonspecific abnormalities (n = 7). Abnormal EEGs were more common in children with remote symptomatic seizures (60%) than in those with idiopathic seizures (38%) (p < 0.003), more common in partial seizures (56%) than in generalized seizures (35%) (p < 0.001), and more common in children age >3 years (52%) than in younger children (12%) (p < 0.001). Records including both awake and sleep tracings were available in 148 (46%) cases. For 122 (38%) only awake tracings and for 51 (16%) only sleep tracings were available. Fifty-nine (40%) of the 148 patients with both an awake and asleep tracing had abnormal EEGs. Of 50 such EEGs with epileptiform abnormalities, 15 (30%) demonstrated the abnormality either only while awake (n = 8) or only while asleep (n = 7). Of 17 patients with EEG slowing, 8 showed slowing only in the awake tracing and 9 showed slowing in both the awake and asleep tracing. Children with even a single unprovoked seizure have a high incidence of EEG abnormalities. Obtaining a combined awake and sleep EEG significantly increases the yield of EEG abnormalities. In children with an idiopathic first seizure, EEG abnormalities are associated with an increased risk of seizure recurrence.     

Intracranial EEG Monitoring in Landau-Kleffner Syndrome Associated with Left Temporal Lobe Astrocytoma

Summary: A 3½-year-old boy developed partial complex seizures with right-sided motor activity, occasionally secondarily generalized at age 18 months. Initial EEG showed left-sided focal epileptiform discharges. Seizures became refractory to antiepileptic drugs (AEDs). At age 3 years, there was severe language deterioration consistent with Landau-Kleffner syndrome (LKS). At that time, an EEG showed almost continual generalized spikes and poly spikes, worse during sleep. Video-EEG showed generalized tonic seizures associated with generalized EEG ictal activity. Magnetic resonance imaging (MRI) showed a cystic and solid lesion of the left hippocampal and parahippocampal gyri without surrounding edema. Subdural strip electrodes under the left temporal and overlying the left frontal lobes demonstrated interictal spikes simultaneously in all recording contacts. Ictal EEG activity occurred in the temporal electrodes 0.2–1 s before appearing in the frontal electrodes. After left temporal lobectomy with subtotal resection of a low-grade astrocytoma, he had an immediate marked decrease in seizures. In 1 month he was seizure-free, and in 6 months had no further seizures and markedly improved language. These findings provide further evidence that left temporal structural epileptogenic lesions may contribute significantly to the pathophysiology of LKS.     

The Landau-Kleffner syndrome: A review

The Landau-Kleffner syndrome or the syndrome of acquired epileptic aphasia was first described in 1957. The disorder is characterised by gradual or rapid loss of language in a previously normal child. All children have abnormal EEG compatible with the diagnosis of epilepsy, however, only 70% have clinical seizures. The present article presents a review of the current knowledge concerning this disorder. Information is provided related to the clinical picture, etiology, pathogenesis, treatment and outcome.

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Zusammenfassung Das Landau-Kleffner-Syndrom oder das Syndrom der erworbenen epileptischen Aphasie wurde erstmals 1957 beschrieben. Die Störung ist charakterisiert durch den allmählichen oder raschen Verlust der Sprache eines zuvor normal entwickelten Kindes. Alle Kinder haben abnorme EEG-Befunde, die mit der Diagnose einer Epilepsie vereinbar sind. Jedoch haben lediglich 70% der Betroffenen klinisch apparente Krampfanfälle. Der vorliegende Artikel faßt den gegenwärtigen Wissensstand zu dieser Störung zusammen. Es werden Informationen zum klinischen Bild, zur Ätiologie, Pathogenese, Behandlung und Verlauf vermittelt.

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Résumé Le syndrome Landau-Kleffner, ou bien le syndrome de l'aphasie épileptique acquise, a été découvert en 1957. Ce dysfonctionnement se charactérise par la perte graduelle ou rapide du langage chez un enfant jusque là normal. Tous les enfants présentent des électro-encéphalogrammes anormaux correspondant à des critères diagnostiques de l'épilepsie, mais 70% d'entre eux seulement ont des attaques cliniques. Cet article présente un survol des connaissances actuelles relatives à ce dysfonctionnement, et se propose de donner des informations quant à son aspect clinique, son étiologie, sa pathogénie, son traitement ainsi que son issue.

     

Aicardi Syndrome: A Longitudinal Clinical and Electroencephalographic Study

Summary: We report clinical and EEC follow-up of 6 children with Aicardi syndrome. Age at seizure onset was <3 months in 5 patients and 4 months in 1 patient. All patients had spasms, and these continued at time of follow-up in 5 patients. Five patients had seizures other than spasms which disappeared during early infancy. Bilateral independent bursts (BIBs) characteristic of Aicardi syndrome were noted in 4 patients. In 1, BIBs showed suppression-burst patterns. BIBs converted to hypsarrhythmia or multifocal spikes with a tendency to BIBs during sleep. BIBs disappeared completely during both waking and sleeping states between the ages of 3 years 1 month and 4 years 9 months. After BIB disappearance, the EEG of 1 patient showed diffuse slow spike-and-wave complexes most of which appeared asynchronously. At onset, 1 patient had early-infantile epileptic encephalopathy with suppression-burst which evolved initially into West syndrome (WS) and then Lennox-Gastaut syndrome (LGS). The other 3 children also had WS.     

Landau-Kleffner综合征的临床特征(附3例报告)

目的探讨Landau-Kleffner综合征(LKS)的临床特征。方法回顾性分析3例LKS患者的临床资料。结果3例临床表现均有获得性失语、癫发作及精神行为异常;脑电图呈局灶性棘波放电,头颅CT及MRI未见异常。经治疗癫发作控制较好,但失语及精神行为异常恢复较慢。结论LKS是以获得性失语和癫发作为临床特征;脑电图可见异常放电。治疗后可部分恢复。     

Landau-Kleffner Syndrome: Consistent Response to Repeated Intravenous γ-Globulin Doses: A Case Report

Summary: Purpose: Although several treatments have been tried for Landau-Kleffner syndrome (LKS) too many patients are refractory to known therapies. We report an 8–year-old girl who failed other therapies but who had a consistent response after treatment with intravenous (i.v.) γ-globulin. Methods: We monitored the girl from the age of 6 years, when she presented with a 6–month history of loss of language with normal hearing, normal brain magnetic resonance imaging (MRI), increased cerebrospinal fluid (CSF) IgG index, and an EEG showing almost continuous, predominantly left-sided spike- and slow-wave complexes. She had no clinical seizures and did not respond to consecutive trials of valproate (VPA), clonazepam (CZP), prednisone, and carbamazepine (CBZ). She received three courses of intravenous (i.v.) γ-globulin; after each course, clinical and electrographic improvement lasted a few months. After each of the initial two eourses, clinical improvement lasted 3–4 months but was followed by recurrence of the spikes on the EEG and by speech deterioration. Results: However, her last remission has been continuous for the past 16 months. Her CSF IgG index became normal after the first i.v. γ-globulin infusion. Conclusions: Based on our experience with this patient and on other investigators' experience, we believe that further research into immunologic mechanisms and therapies of this syndrome are warranted.     

Case of Landau-Kleffner Syndrome Secondary to Inflammatory Demyelinating Disease

Summary: A 6-year old girl developed acquired aphasia with epilepsy and a paroxysmal EEG (Landau-Kleffner syndrome). Isoelectric CSF focusing showed oligoclonal IgG bands. Small lesions were visualized in periventricular left frontal white matter and right parietal lobe centrum semiovale with magnetic resonance imaging (MRI). After a week of ACTH therapy, the EEG paroxysmal activity disappeared; during the next few months, the language disorder improved. Further MRI examination showed a decrease in size and signal of the left frontal lesions, with localized white matter atrophy, dilatation of the subarachnoidal spaces, and disappearance of the right parietal lesion. The clinical and neuroradiologic features and the laboratory data suggest an acute disseminated encephalomyelitis.