Search

Resumen: Introducción: La punta-onda continua durante el sueño lento (POCS) es un trazado electroencefalográfico característico, que aparece en la infancia y que en ocasiones condiciona un deterioro cognitivo. Este patrón electroencefalográfico puede aparecer tanto en determinados síndromes epilépticos como en la evolución de epilepsias idiopáticas y sintomáticas. El objetivo de nuestro estudio es analizar las características epidemiológicas y clínicas de pacientes que presentan en algún momento de su evolución POCS, describir la respuesta a distintos tratamientos y estudiar factores predictores de su evolución. Métodos: Estudio observacional retrospectivo de pacientes pediátricos con POCS seguidos en un hospital terciario en el periodo de noviembre 1997 a noviembre 2017. Resultados: Obtuvimos una muestra de 25 pacientes (68% varones). El 76% presentaba de base alteraciones en pruebas de neuroimagen o retraso psicomotor (POCS secundaria). El 24% restante eran niños sanos o con epilepsias benignas (POCS primaria). La edad media al inicio de la POCS fue de 6,7 años, siendo menor en los casos secundarios. Durante el periodo de POCS, el 72% presentó alguna manifestación clínica añadida. Todos recibieron combinaciones de antiepilépticos, siendo eficaces en el 36%. La POCS cesó en el 72%, siendo más probable el cese cuanto más tarde se hubiera instaurado. Un tercio tuvo alguna secuela, principalmente alteraciones cognitivas y del comportamiento, más frecuentes en POCS secundaria y en los pacientes en que duró más tiempo. Conclusiones: El trazado electroencefalográfico de POCS, aunque infrecuente, supone un reto terapéutico. Es importante seguir a los pacientes con epilepsia, especialmente si asocia deterioro neurológico, para detectar la presencia POCS e iniciar tratamiento precoz. Abstract: Introduction: Continuous spikes and waves during slow sleep (CSWS) is an EEG pattern that appears during childhood, and is often associated with cognitive impairment. It can appear in the course of epileptic syndromes, as well as in benign epilepsy. The aim of this study is to analyse epidemiological and clinical characteristic of patients with CSWS, in order to describe possible predictive factors in their outcome. Methods: A retrospective study was conducted on paediatric patients with CSWS treated in a third-level hospital from November 1997 to November 2017. Results: The study included 25 patients (68% male), of whom 76% had abnormalities in the neuroimaging or suffered from psychomotor development disorder (secondary CSWS). The rest were healthy, or diagnosed with idiopathic epilepsy. The mean age of onset of CSWS was 6.7 years, but earlier in the secondary CSWS cases. Symptoms were present during the CSWS episode in 72% of cases. All of them were treated with antiepileptic drugs, which were effective in 36%. CSWS stopped in 72%, and remission was longer if the CSWS onset occurred at an older age. One-third (33%) presented with sequelae, mostly cognitive and behavioural alterations. Outcome was poorer in those with secondary CSWS and, in those whose CSWS started at an earlier age and lasted longer. Conclusion: The CSWS pattern, although rare, is still a therapeutic challenge. A close follow-up of the patients with epilepsy is important, especially if associated with cognitive impairment, in order to establish an early diagnosis and treatment.

We report a case of a 48-year-old woman who was diagnosed with Landau-Kleffner syndrome (LKS) at the age of 4 and reassessed by the same neurologist four decades later. While her seizures abated by the time she was 12 years old, she was left with chronic aphasia, despite receiving optimal care. Although she graduated from high school, started her own family, and was gainfully employed, she was vulnerable in situations that required clear communication. This case reflects successful management of an otherwise debilitating condition and reminds us of the vulnerability of adults with LKS and their need for a life-long support., Highlights • Acquired epileptiform aphasia, and LKS as its variant, has lifelong consequences. • Even those who recover relatively well from LKS face lifelong social, communication and economic challenges. • Educational and psychological support with effective social restructuring may be necessary for adults with LKS.

Epileptic encephalopathy with continuous spike-waves during slow-wave sleep (CSWS) is a spectrum of epileptic conditions best defined by the association of cognitive or behavioral impairment acquired during childhood and not related to another factor other than the presence of abundant interictal epileptiform discharges (IED) during sleep, which tend to diffuse over the whole scalp. It is part of the childhood focal epileptic syndromes, some cases being idiopathic and overlapping with benign rolandic epilepsy, and others being symptomatic of a structural brain lesion. Landau-Kleffner syndrome (LKS) is a particular presentation where acquired aphasia is the core symptom. Clinical, neurophysiological, and cerebral glucose metabolism data support the hypothesis that IED play a prominent role in the cognitive deficits by interfering with the neuronal networks at the site of the epileptic foci but also at distant connected areas. Therefore, the treatment should aim to suppress IED. This may be achieved using conventional antiepileptic drugs, but corticosteroids seem to have more pronounced and sustained efficacy. Outcome for epilepsy is usually good, CSWS being an age-dependent EEG pattern, whereas outcome for cognition, language, and behavior is variable. Rehabilitation represents an important part of the treatment and visual forms of language should be encouraged in children with LKS.

Landau–Kleffner syndrome (LKS) is an acquired epileptic aphasia in which children 3–8 years old, who already have developed normal speech, experience language regression with verbal auditory agnosia, abnormal epileptiform activity, and behavioral disturbances. Its pathophysiology involves synchronization, presumably through thalamic-related neuronal networks, of epileptiform activity in speech areas leading to marked discharge activation in sleep. There are no controlled studies of LKS therapy. Current treatment protocols usually include steroids or valproate as well as older and newer antiepileptic drugs. Emerging therapies include high-dose diazepam, intravenous gammaglobulin, and multiple subpial transection.

Landau-Kleffner syndrome (LKS) is a rare childhood neurological disorder characterized by two main clinical features: epilepsy and the occurrence of acquired aphasia in previously normally developing children. Severe auditory agnosia and progressive loss of acquired speech abilities encapsulate the language impairments observed in children with LKS. Clinical and linguistic aspects of this childhood neurological disorder are reviewed and hypotheses underlying the comprehension of language regression in LKS are discussed. Altogether, LKS provides interesting information on the critical period of language maturation.

Publisher Summary In their original description of the syndrome of “acquired aphasia with convulsive disorder,” Landau and Kleffner (1957) suggested “that persistent convulsive discharges in brain tissue largely concerned with linguistic communication result in the functional ablation of these areas for normal linguistic behavior.” In further case studies, the observation of continuous epileptic discharges in electroencephalograms (EEGs) recorded during sleep agreed with this early suggestion. Although several group studies emphasized the almost parallel fluctuation of aphasic disorders and EEG abnormalities, the causal relationship between epileptiform EEG discharges and the language defect remains a matter of debate. Another subject of discussion concerns the outcome of aphasia after recovery of epilepsy that typically occurs at the beginning of adolescence. In the Landau-Kleffner syndrome (LKS), the prognosis of aphasia varies in a manner opposite that observed after structural lesions of the left hemisphere. To further elucidate the pathophysiological basis of aphasia and its poor outcome in LKS, this chapter reexamines five clinical studies of LKS with particular emphasis on electrophysiological and metabolic findings and their relationship to neuropsychological deficits. The data presented and discussed covers a follow-up period extending for each case from the active period to the late recovery phase of epilepsy lasting from 7 to 15 years. The chapter summarizes the clinical histories and neuropsychological findings gathered during the period when the children were aphasic and epileptic and after recovery and focuses on the experimental data supporting focal or regional cerebral dysfunction underlying this particular acquired childhood aphasia.

Clinical neuropsychological and linguistic aspects of the Landau–Kleffner syndrome (LKS, acquired childhood epileptic aphasia) are reviewed. Unlike child aphasia following focal lesions, LKS is characterized by severe auditory comprehension disorders and by a strong relationship between age of onset and outcome: the older the child at onset, the better the outcome. Alternative hypotheses underlying comprehension disorders (purely linguistic versus sensory higher-order auditory processing deficit) are discussed.