Specific language impairment versus Landau-Kleffner syndrome

The occurrence of sleep electroencephalography (EEG) abnormalities in some children with specific language impairment (SLI), the various forms of language dysfunction patterns seen in children with benign childhood epilepsy with centrotemporal spikes (BECTS), and finally the acquired aphasia in Landau-Kleffner syndrome (LKS) indicate a large spectrum of interactions between language and epilepsy. As such, the question is whether SLI and LKS should rather be considered along a continuum or as two entirely distinct entities. In addition, the rationale for using antiepileptic medications in rare forms of SLI is discussed.     

Phonological short-term memory networks following recovery from Landau and Kleffner syndrome

Landau-Kleffner syndrome (LKS) is a rare acquired aphasia occurring in otherwise healthy children, together with spike-wave discharges predominating over superior temporal regions and activated by sleep. Although the outcome of language abilities is variable, a residual impairment in verbal short-term memory (STM) is frequent. This STM deficit might be related to the persistent dysfunction of those temporal lobe regions where epileptic discharges were observed during the active phase of the disorder. We tested this hypothesis by measuring brain activation during immediate serial recall of lists of 4 words, compared to single word repetition, using H(2) (15)O positron emission tomography (PET), in 3 LKS patients after recovery and in 14 healthy controls. The patients (TG, JPH, and DC) had shown abnormally increased or decreased glucose metabolism in left or right superior temporal gyrus (STG) at different stages during the active phase of their disease. At the time of this study, the patients were 6-10 years from the active phase of LKS. Results showed that Patients JPH and DC had impaired performance in the STM condition, whereas TG showed near normal performance. PET data showed that JPH and DC activated significantly less than controls left and right posterior STG. TG, having near normal STM performance, showed increased activity in the posterior part of the right STG. These data suggest that impaired verbal STM at late outcome of LKS might indeed be related to a persistent decrease of activity in those posterior superior temporal gyri that were involved in the epileptic focus during the active phase.     

Outcome of multiple subpial transections for autistic epileptiform regression.

Treatment options for atypical forms of Landau-Kleffner syndrome (LKS) are not well delineated. Many patients with typical LKS fail to respond to antiepileptic drug treatment, but some benefit from multiple subpial transections (MSTs). The authors report seven patients with autism or autistic epileptiform regression who responded in varying degrees to MSTs after failed medical management. These patients derived from an original cohort of 36 children (29 males, seven females, ranging from 2 years, 3 months to 11 years, 3 months, mean age = 5 years, 8 months) with a history of language delay or regression, as well as varying degrees of social and behavioral abnormalities, who were evaluated with video-electroencephalogram (EEG) monitoring over a 2-year period. Fifteen patients had clinical seizures (11 of the 19 children with autistic epileptiform regression and four of 12 autistic children). Epilepsy was refractory to medication in seven. Surgical treatment variously involved MSTs of the left neocortex in temporal, parietal, and frontal regions, often including regions within the classic perisylvian language areas. One patient also had a left temporal lobectomy. In all seven patients, seizure control or EEG improved after MSTs. Language, social, and overall behavior improved to a moderate degree, although improvements were temporary in most. Autistic epileptiform regression resembles LKS in that both may respond to MST. MST is used to treat epilepsy in eloquent regions. The responsiveness of autistic epileptiform regression to MST buttresses the argument that autistic epileptiform regression is a form of focal epilepsy.     

Autism and autistic epileptiform regression with occipital spikes

The electroencephalographs abnormalities seen in Landau-Kleffner syndrome (LKS) (language deterioration) are non-specific, and consist of a variety of epileptiform discharge patterns including continuous slow spike-wave discharges during sleep, focal sharp waves with spikes, and centrotemporal (rolandic) spikes. Similarly, the EEG abnormalities seen in autistic epileptiform regression (language and social/behavioral deterioration) are nonspecific and overlap with those seen in LKS. By contrast, distinct epilepsy syndromes in otherwise normal children occur in the EEG-deflned benign focal epilepsies of childhood. Occipital spikes or spike-wave present either in the older child with visual symptoms and headache or in the younger child with autonomic symptoms followed by brief or prolonged partial motor seizures. Seven young children (five from a consecutive series of 42) presenting clinically with autism or autistic regression and possible or definite seizures, whose EEGs revealed occipital spikes or spike-wave characteristic of the benign epilepsies, are reported. Although occipital spikes are commonly seen in young children as an age-dependent EEG-defined benign focal epilepsy, their high frequency in this population with cognitive difficulties suggests a possible causal relation. The effects of the epileptiform discharge on cognitive functioning presumably reflect extension into temporal and parietal lobes, rather than occipital disturbances per se.     

Changing perspectives on Landau-Kleffner syndrome

Landau-Kleffner syndrome (LKS) is a childhood disorder characterized by an acquired aphasia that emerges in association with epileptiform electroencephalographic abnormalities. The language loss is often characterized by a severe disturbance of auditory language comprehension (verbal auditory agnosia) combined with a substantial disruption of expressive language. Comorbid behavioral disturbances commonly involve hyperactivity and attentional problems but sometimes encompass a more pervasive pattern of difficulties resembling an autism spectrum disorder. Now one the most frequently described forms of acquired aphasia in children, LKS has had a profound influence on both neurological practice and cognitive neuroscience. Here, we review current conceptualizations of LKS, consider its pleomorphic manifestations and discuss existing and future diagnostic issues and dilemmas. The potential relevance of LKS to understanding other disorders, including autistic regression, is considered.     

Landau-Kleffner syndrome and CSWS syndrome: Treatment with intravenous immunoglobulins

This study reports results of therapy with immunoglobulin in children with Landau-Kleffner syndrome (LKS) or the syndrome of continuous spikes and waves during sleep (CSWS syndrome). In a prospective study, children diagnosed between 2002 and 2006 with either LKS or CSWS syndrome were treated soon after diagnosis with intravenous courses of immunoglobulin (IVIg). We compared the results with those reported in the literature and with data from a retrospective survey of our earlier patients. Six children (two girls), aged 4–9 years, were included. Three had LKS, and three had CSWS syndrome. One child—with typical LKS—had been treated with prednisone before (without response). No patient had seizures during IVIg treatment and follow-up. Their electroencephalography (EEG) findings did not improve. Neuropsychological improvement occurred in one child with CSWS syndrome. Three children did not show any beneficial effect; they were subsequently treated with steroids, one with a clearly positive result. We conclude that successful treatment of LKS and CSWS syndrome with IVIg occurs occasionally. However, the improvement cannot always be clearly attributed to this. It might also reflect the natural course of the disease. Although the temporal relation between IVIg treatment and clinical improvement cannot be denied in individual patients, its real value remains to be determined.     

获得性癫痫性失语综合征的临床特点分析

目的 研究中国人获得性癫痫性失语(Landau-Kleffner Syndrome,LKS)的临床、脑电图及治疗特点.方法 对中国大陆地区报道的文献中71例LKS患儿的临床资料进行回顾总结,并结合文献进行探讨.结果 获得性癫痫失语均发作于儿童期,临床均有失语及脑电图癫痫样放电,其中以混合性失语及腩电图棘-慢复合波为多见.多数临床有癫痫发作,听力均无异常,多数伴有精神行为异常.癫痫发作用抗癫痫药物控制良好,经皮质激素及免疫球蛋白的治疗,失语大多能改善.结论 中国儿童获得性癫痫性失语主要临床表现为获得性失语和癫痫发作,多伴有其它精神行为症状.EEG常见颞区的限局性放电,失语表现为听觉失认.早期诊断并采取包括抗癫痫药物和皮质激素应用的综合治疗,患者的预后总体良好.     

Multiple subpial transection in Landau-Kleffner syndrome

We have considered multiple subpial transection (MST) as a treatment option for Landau-Kleffner syndrome (LKS) for the past 6 years. The effect of this technique on language and cognitive ability, behaviour, seizures, and EEG abnormalities is analysed here. Five children (4 males, 1 female; aged 5.5 to 10 years) underwent MST with sufficiently detailed pre- and postoperative data for analysis. Behaviour and seizure frequency improved dramatically after surgery in all children. Improvement in language also occurred in all children, although none improved to an age-appropriate level. All five had electrical status epilepticus in sleep (ESES) before surgery, which was eliminated by the procedure. One child has had an extension of his MST due to the recurrence of ESES and accompanying clinical deterioration with good effect. An attempt is made to set the effect of MST against the natural history of the condition. MST is an important treatment modality in LKS, although the timing of this intervention and its effect on final language outcome remains to be defined.     

Sign language in Landau-Kleffner syndrome

This article reviews the history of sign language (SL) and the rationale for its use in children with profound auditory agnosia due to Landau-Kleffner syndrome (LKS), illustrated by studies of children and adults followed for many years and rare cases from the literature. The reasons that SL was successful and brought some children out of isolation while it could not be implemented in others are discussed. The nowadays earlier recognition and treatment of LKS and better awareness of the crucial need to maintain communication have certainly improved the outcome of affected children. Alternatives to oral language, even for less severe cases, are increasingly accepted. SL can be learned at different ages with a clear benefit, but the ambivalence of the patients and their families with the world and culture of the deaf may sometimes explain its refusal or limited acceptance. There are no data to support the fear that SL learning may delay or prevent oral language recovery in children with LKS. On the contrary, SL may even facilitate this recovery by stimulating functionally connected core language networks and by helping speech therapy and auditory training.     

The assessment of auditory function in CSWS: Lessons from long-term outcome

In Landau-Kleffner syndrome (LKS), the prominent and often first symptom is auditory verbal agnosia, which may affect nonverbal sounds. It was early suggested that the subsequent decline of speech expression might result from defective auditory analysis of the patient's own speech. Indeed, despite normal hearing levels, the children behave as if they were deaf, and very rapidly speech expression deteriorates and leads to the receptive aphasia typical of LKS. The association of auditory agnosia more or less restricted to speech with severe language decay prompted numerous studies aimed at specifying the defect in auditory processing and its pathophysiology. Long-term follow-up studies have addressed the issue of the outcome of verbal auditory processing and the development of verbal working memory capacities following the deprivation of phonologic input during the critical period of language development. Based on a review of neurophysiologic and neuropsychological studies of auditory and phonologic disorders published these last 20 years, we discuss the association of verbal agnosia and speech production decay, and try to explain the phonologic working memory deficit in the late outcome of LKS within the Hickok and Poeppel dual-stream model of speech processing.     

A pilot study transitioning children onto levetiracetam monotherapy to improve language dysfunction associated with benign rolandic epilepsy

Benign rolandic epilepsy (BRE) and Landau-Kleffner syndrome (LKS) are similar epilepsy syndromes with sleep-accentuated epileptiform activity, sporadic seizures, and language dysfunction. Levetiracetam has been associated with improved language function in LKS and seizure reduction in BRE. We hypothesized levetiracetam would improve language function in children with BRE. A pilot study was performed with six children (aged 6-12) with BRE and evidence of impaired auditory comprehension and verbal memory. Children were transitioned from their current anticonvulsant to 40 mg/kg/day levetiracetam over a 2-week period and retested at 6 months. At 6 months, three of four children with baseline auditory comprehension impairments performed normally (P=0.06), and five had improved auditory verbal memory (P=0.08). Seizures improved in five, decreasing from 2.7 to 1.0 seizure per 6 months (P=0.11). Results from this pilot study suggest that levetiracetam may have a beneficial effect on language in children with BRE.     

Possible involvement of the tip of temporal lobe in Landau-Kleffner syndrome

Landau-Kleffner syndrome (LKS) is a childhood disorder of unknown etiology characterized by an acquired aphasia and epilepsy. We have performed comprehensive neurofunctional studies on an 8-year-old girl with typical LKS, with the aim of identifying lesions that may be responsible for her condition. 18F-fluoro-D-glucose (FDG) positron emission computed tomography (PET), 11C-Flumazenil (FMZ) PET, 99mTc-hexamethylpropyleneamine oxime single photon emission computed tomography (SPECT) and magnetoencephalography were performed before and after changes to the patient's medication led to a clinical improvement. Interictal SPECT showed hypoperfusion in the left frontal, left temporal, and left occipital lobes. 18F-FDG PET demonstrated a decrease in glucose metabolism medially in both temporal lobes and superiorly in the left temporal lobe. 11C-FMZ PET revealed a deficit in benzodiazepine receptor binding at the tip of the left temporal lobe. Magnetoencephalography demonstrated equivalent current dipoles located superiorly in the left temporal lobe. Our results suggest that the tip of the left temporal lobe plays an important role in the pathogenesis of LKS in our patient.     

Atypical Evolutions of Benign Localization‐Related Epilepsies in Children: Are They Predictable?

PURPOSE: To emphasize that, in some patients, different atypical evolutions occur in the course of so-called benign focal epilepsies of childhood (BFEC) and to promote interest in finding clinical and/or electroencephalographic (EEG) clues to which patients might be prone to these risky evolutions. METHODS: Twenty-six patients who started with the typical clinical and EEG features of benign childhood epilepsy with centrotemporal spikes (BCECTS) but who had reversible or persistent, serious epileptic events including status epilepticus and language, cognitive, or behavioral impairments were followed for 相似文献   

Episodic receptive aphasia in a child with Landau-Kleffner Syndrome: PET correlates

We report a four-year-old boy with Landau-Kleffner Syndrome (LKS) characterized by episodic receptive aphasia lasting for few weeks followed by gradual recovery of baseline language functions. Neuropsychological evaluation during an episode showed severe impairment in verbal skills and comprehension, but relative preservation of non-verbal skills. Although he could carry on a conversation during remission, neuropsychological evaluation demonstrated findings reflective of receptive language deficits. Prolonged EEG disclosed frequent sharp-wave activity in the left and right temporal regions but no electrographic seizures. Glucose metabolism PET scan during the fourth episode of aphasia revealed intense hypermetabolism in the left temporal neocortex. Awake EEG during the PET tracer uptake period showed 6.0 spikes/min in the left temporal region and 4.0 spikes/min in the right. A repeat PET scan during remission showed hypometabolism in the left temporal cortex. Awake EEG during the FDG uptake period showed 16.0 spikes/min in the right temporal region and 0.3 spikes/min in the left. During his fifth aphasic episode, EEG (without PET) showed 0.16 spikes/min in the right temporal region and none in the left. Intermittent short episodes of predominantly receptive aphasia with near-total recovery between episodes can be one of the clinical presentations of LKS. This case illustrates the dynamic changes of glucose metabolism in the temporal lobe during episodes of aphasia and remission in a case with LKS. The clinical course of our patient with transient EEG and PET findings suggest that glucose metabolism in LKS cannot be attributed solely to interictal epileptiform activities on scalp EEG.     

Reduced superior temporal gyrus volume in young offspring of patients with schizophrenia

OBJECTIVE: The superior temporal gyrus, a heteromodal auditory and language association cortex, has been found to be smaller in patients with schizophrenia than in normal subjects. However, genetic and/or neurodevelopmental underpinnings of superior temporal gyrus alterations are unknown. Nonpsychotic children with greater genetic risk for schizophrenia exhibit language deficits. The authors studied the superior temporal gyrus in nonpsychotic children at risk for schizophrenia. METHOD: Magnetic resonance imaging was used to measure the right and left superior temporal gyrus of 29 young nonpsychotic subjects who had a parent with schizophrenia and 27 age- and sex-matched comparison subjects who had no family psychiatric history. RESULTS: After controlling for age and intracranial volume, the authors found that the volumes of the right and left superior temporal gyrus of the subjects at risk for schizophrenia were significantly smaller than those of the comparison subjects. Comparison subjects, but not at-risk subjects, showed an inverse correlation between age and left superior temporal gyrus volume. CONCLUSIONS: These findings provide new evidence that superior temporal gyrus abnormalities may result from genetically mediated developmental deviance reflecting greater susceptibility to schizophrenia. Further studies and follow-up will lead to greater understanding of the role of the superior temporal gyrus in the premorbid vulnerability to schizophrenia.     

Efficacy of very high dose steroid treatment in a case of Landau-Kleffner syndrome

Landau-Kleffner syndrome (LKS) is an acquired childhood aphasia associated with paroxysmal bitemporal electroencephalogram (EEG) abnormalities and, sometimes, clinical seizures. We report the case of a female aged 5 years 6 months who presented clinically with apparent hearing loss, deterioration in speech, and seizure activity over 12 days. The female had previous detailed speech/language assessments at 3 to 4 years of age due to articulation delay. LKS was diagnosed on EEG with bitemporal spike and wave activity during sleep. The patient was treated with high dose prednisolone 3mg/kg/day, intensive speech/language therapy, and followed a modified educational program. We recorded a marked regression in receptive and expressive language skills, as well as her speech, language, and cognitive profiles before and during treatment with prednisolone, during an 18-month follow-up period. The patient demonstrated an excellent clinical response highlighting the importance of a multidisciplinary approach to management of LKS.     

Landau-Kleffner syndrome: long-term follow-up

Purpose

Landau–Kleffner syndrome (LKS) is a rare entity characterized by epilepsy and aphasia. It occurs in previously normal children, usually between three and seven years of age. The long-term outcome of LKS is not completely clear. The aim of this study is to verify the long-term follow-up of a group of patients with LKS, focusing on clinical and electroencephalographic (EEG) aspects, and quality of life. Methods: This was a transversal study. Between November 2006 and April 2007 seven patients with previous diagnosis of LKS were interviewed. They had had a follow-up of three to 16 years after their disease onset. They were all males between the ages of eight and 27 years old. All patients had normal MRI. Parents and/or patients were interviewed by one of the authors using a structured questionnaire. The Vineland Adaptive Behavior Scales, the Conner’s Rating Scales – Revised, and Short-Form Health Survey (SF 36) were used. Each patient had a prolonged interictal EEG recording. All patients had normal MRI. Results: The present investigation revealed that two patients still have seizures several years after epilepsy onset. One patient had total and three others had partial remission of language disturbance, while three patients still have aphasia and verbal auditory agnosia. With respect to quality of life, only one of our patients has a normal life at present. The remaining six patients with some sort of limitation consider the aphasia/agnosia to be the main difficulty in their lives. Five patients have normal EEGs. Conclusions: The long-term follow-up of patients with LKS shows that epilepsy and EEG abnormalities do not always disappear. Language disturbances tend to persist in most patients. The age of onset of language dysfunction does not seem to correlate with the prognosis for recovery of language function. Patients with LKS have an overall poor quality of life, mostly due to language difficulties.     

Cognitive and behavioral problems in children with centrotemporal spikes

Atypical features in benign epilepsy of childhood with centrotemporal spikes (BECTS) are not uncommon. There are children with BECTS who do not have a benign outcome in terms of neuropsychologic functioning. BECTS have been linked with Landau-Kleffner syndrome (LKS) and continuous spikes and waves during slow sleep (CSWS). At the Medical College of Georgia from January 1988 to June 1999, 78 children, ages 2-16 years, were identified to have electroencephalogram evidence of centrotemporal spikes. Their medical records were reviewed for developmental history, behavioral problems, and school performance. Children with structural lesions/other epileptic syndromes were excluded. Fifty-six demonstrated a history of clinical seizures compatible with BECTS and 22 demonstrated centrotemporal spikes without clinical seizures. Among all children with centrotemporal spikes, 9% (n = 7) were diagnosed with mild intellectual disability (intelligence quotient < 70), 10% (n = 8) with borderline functioning, 31% (n = 24) with behavioral problems, and 17% (n = 13) with specific learning disabilities. Three children with BECTS experienced language delay and regression. Seizure control for BECTS usually is achieved without much difficulty, with excellent long-term prognosis. However, the data presented indicate that a large number of BECTS patients exhibit learning or behavior problems that require intervention. A small number may demonstrate language outcome similar to children with LKS and CSWS.     

Abnormal asymmetry in language association cortex in autism

Autism is a neurodevelopmental disorder affecting cognitive, language, and social functioning. Although language and social communication abnormalities are characteristic, prior structural imaging studies have not examined language-related cortex in autistic and control subjects. Subjects included 16 boys with autism (aged 7-11 years), with nonverbal IQ greater than 80, and 15 age- and handedness-matched controls. Magnetic resonance brain images were segmented into gray and white matter; cerebral cortex was parcellated into 48 gyral-based divisions per hemisphere. Asymmetry was assessed a priori in language-related inferior lateral frontal and posterior superior temporal regions and assessed post hoc in all regions to determine specificity of asymmetry abnormalities. Boys with autism had significant asymmetry reversal in frontal language-related cortex: 27% larger on the right in autism and 17% larger on the left in controls. Only one additional region had significant asymmetry differences on post hoc analysis: posterior temporal fusiform gyrus (more left-sided in autism), whereas adjacent fusiform gyrus and temporooccipital inferior temporal gyrus both approached significance (more right-sided in autism). These inferior temporal regions are involved in visual face processing. In boys with autism, language and social/face processing-related regions displayed abnormal asymmetry. These structural abnormalities may relate to language and social disturbances observed in autism.