Pulse Methylprednisolone Therapy in Landau-Kleffner Syndrome

Pharmacologic treatment of intractable epilepsy in children: a syndrome-based approach

The successful pharmacologic treatment of intractable childhood epilepsy is predicated upon an accurate classification of the epilepsy syndrome. The selection of an antiepileptic drug is facilitated by the knowledge of syndrome-specific efficacy, the anticipation of potential side effects, and a careful risk-benefit assessment tailored to each patient. As such, the identification of comorbidities and careful monitoring for treatment-emergent adverse events, especially cognitive and behavioral effects, is of utmost importance. Especially in refractory cases, polypharmacy may increase the likelihood of side effects, but carefully chosen combinations can result in synergistic benefit. For most epilepsy syndromes, newer antiepileptic drugs typically yield equivalent efficacy and superior tolerability. Nevertheless, continued research is needed to further contrast the syndrome-specific efficacy and tolerability of available drugs and to foster the development of new agents with superior efficacy and side effect profiles.

Immune therapy in autism: historical experience and future directions with immunomodulatory therapy

Autism affects 1 in 110 new births, and it has no single etiology with uniform agreement. This has a significant impact on the quality of life for individuals who have been diagnosed with autism. Although autism has a spectrum quality with a shared diagnosis, it presents a uniquely different clinical appearance in each individual. Recent research of suspected immunological factors have provided more support for a probable immunological process or for processes that may play a role in the acquisition of an autistic condition. These factors include prenatal, genetic, and postnatal findings, as well as the discovery of a dysfunctional chronic pro-inflammatory state in brain tissue and cerebrospinal fluid in subsets of autistic patients. These findings offer new theories that may lead to the development of disease modification or preventative therapeutic options in the near future. This article reviews prenatal, genetic, and observed immune aspects of the autism condition that may be risk factors in the presentation of the autistic clinical phenotype. Historical immune interventions in autism are reviewed and potential new therapies and interventions are discussed.

Management of Landau-Kleffner syndrome

Landau-Kleffner syndrome (LKS) is an acquired epileptic aphasia disorder in which children, usually 3-8 years of age who have developed age-appropriate speech, experience language regression with verbal auditory agnosia, abnormal epileptiform activity, behavioral disturbances, and sometimes overt seizures. There are no controlled clinical trials investigating the therapeutic options for LKS. Only open-label data are available. Early diagnosis and initiation of prompt medical treatment appear to be important to achieving better long-term prognosis.Several antiepileptic drugs have been reported to be beneficial in treating this syndrome. These include valproic acid (valproate sodium), diazepam, ethosuximide, clobazam, and clonazepam. Reports on the efficacy of lamotrigine, sultiame, felbamate, nicardipine, vigabatrin, levetiracetam, vagal nerve stimulation, and a ketogenic diet are few and more experience is needed. Carbamazepine and possibly phenobarbital and phenytoin have been reported to occasionally exacerbate the syndrome. As initial therapy, valproic acid or diazepam is often empirically chosen. Subsequently, other antiepileptic drugs, corticosteroids, or intravenous immunoglobulin (IVIG) therapy are often used. Corticosteroid therapy should probably not be delayed more than 1-2 months after the initial diagnosis. Various corticosteroid regimens including oral prednisone and, recently, high doses of intravenous pulse corticosteroids, as well as corticotropin (adrenocorticotropic hormone) have been reported to be effective in LKS. Oral corticosteroids are used more often and usually need to be maintained for a long period of time to prevent relapses. The use of IVIG has been associated with an initial dramatic response in only a few patients. In our experience, a long-term worthwhile improvement has been noted in only 2 of 11 patients. These two patients had an immediate response to IVIG initially and after relapses before eventually achieving a long-term sustained remission. Surgical treatment by multiple subpial transection, which is reserved for patients who have not responded to multiple medical therapies, has been followed in selected cases by a marked improvement in language skills and behavior. However, a widely accepted consensus about suitable candidates for this surgery and about its efficacy is still lacking. Speech therapy, including sign language, and a number of classroom and behavioral interventions are helpful in managing LKS, and should be used in all patients.

Cognitive deterioration and electrical status epilepticus during slow sleep

The results of long-term follow-up of 10 children with global or specific cognitive deterioration and, on the electroencephalogram, electrical status epilepticus during sleep (ESES) are described. They were referred because of cognitive deterioration and underwent repeated neurological and neuropsychological examinations and all-night electroencephalography. A previous cognitive level was known or could be estimated in all. Seven children had a continuous spikes and waves during sleep (CSWS) syndrome, with global cognitive deterioration in four and more specific cognitive decline in three, and another three children had Landau-Kleffner syndrome (LKS). Of the last three, two children never had seizures, while the other had localization-related epilepsy. No children experienced aggravation of clinical seizures. However, therapy was disappointing. Cognitive dysfunction did not respond to valproate and/or benzodiazepines in 9 of the 10 children. A frontal epileptic focus was found in 5 of 7 children with CSWS, and a left temporal focus in 2 of 3 children with LKS. The ESES persisted in CSWS for 5-9 years and in LKS for 1-5 years, and disappeared at puberty. Good cognitive recovery after disappearance of ESES occurred in only one child, and partial recovery in four. An unfavorable prognosis of cognitive deterioration seems to be related to long-duration ESES and/or early onset epileptic activity. The authors are of the opinion that cognitive deterioration in children, with or without manifest epileptic seizures, should mandate electroencephalographic investigation during sleep.

Magnetoencephalographic patterns of epileptiform activity in children with regressive autism spectrum disorders

BACKGROUND

One-third of children diagnosed with autism spectrum disorders (ASDs) are reported to have had normal early development followed by an autistic regression between the ages of 2 and 3 years. This clinical profile partly parallels that seen in Landau-Kleffner syndrome (LKS), an acquired language disorder (aphasia) believed to be caused by epileptiform activity. Given the additional observation that one-third of autistic children experience one or more seizures by adolescence, epileptiform activity may play a causal role in some cases of autism.

OBJECTIVE

To compare and contrast patterns of epileptiform activity in children with autistic regressions versus classic LKS to determine if there is neurobiological overlap between these conditions. It was hypothesized that many children with regressive ASDs would show epileptiform activity in a multifocal pattern that includes the same brain regions implicated in LKS.

DESIGN

Magnetoencephalography (MEG), a noninvasive method for identifying zones of abnormal brain electrophysiology, was used to evaluate patterns of epileptiform activity during stage III sleep in 6 children with classic LKS and 50 children with regressive ASDs with onset between 20 and 36 months of age (16 with autism and 34 with pervasive developmental disorder-not otherwise specified). Whereas 5 of the 6 children with LKS had been previously diagnosed with complex-partial seizures, a clinical seizure disorder had been diagnosed for only 15 of the 50 ASD children. However, all the children in this study had been reported to occasionally demonstrate unusual behaviors (eg, rapid blinking, holding of the hands to the ears, unprovoked crying episodes, and/or brief staring spells) which, if exhibited by a normal child, might be interpreted as indicative of a subclinical epileptiform condition. MEG data were compared with simultaneously recorded electroencephalography (EEG) data, and with data from previous 1-hour and/or 24-hour clinical EEG, when available. Multiple-dipole, spatiotemporal modeling was used to identify sites of origin and propagation for epileptiform transients.

RESULTS

The MEG of all children with LKS showed primary or secondary epileptiform involvement of the left intra/perisylvian region, with all but 1 child showing additional involvement of the right sylvian region. In all cases of LKS, independent epileptiform activity beyond the sylvian region was absent, although propagation of activity to frontal or parietal regions was seen occasionally. MEG identified epileptiform activity in 41 of the 50 (82%) children with ASDs. In contrast, simultaneous EEG revealed epileptiform activity in only 68%. When epileptiform activity was present in the ASDs, the same intra/perisylvian regions seen to be epileptiform in LKS were active in 85% of the cases. Whereas primary activity outside of the sylvian regions was not seen for any of the children with LKS, 75% of the ASD children with epileptiform activity demonstrated additional nonsylvian zones of independent epileptiform activity. Despite the multifocal nature of the epileptiform activity in the ASDs, neurosurgical intervention aimed at control has lead to a reduction of autistic features and improvement in language skills in 12 of 18 cases.

CONCLUSIONS

This study demonstrates that there is a subset of children with ASDs who demonstrate clinically relevant epileptiform activity during slow-wave sleep, and that this activity may be present even in the absence of a clinical seizure disorder. MEG showed significantly greater sensitivity to this epileptiform activity than simultaneous EEG, 1-hour clinical EEG, and 24-hour clinical EEG. The multifocal epileptiform pattern identified by MEG in the ASDs typically includes the same perisylvian brain regions identified as abnormal in LKS. When epileptiform activity is present in the ASDs, therapeutic strategies (antiepileptic drugs, steroids, and even neurosurgery) aimed at its control can lead to a significa