Tracy A. Glauser

Revised terminology and concepts for organization of seizures and epilepsies: report of the ILAE Commission on Classification and Terminology, 2005-2009.

The International League Against Epilepsy (ILAE) Commission on Classification and Terminology has revised concepts, terminology, and approaches for classifying seizures and forms of epilepsy. Generalized and focal are redefined for seizures as occurring in and rapidly engaging bilaterally distributed networks (generalized) and within networks limited to one hemisphere and either discretely localized or more widely distributed (focal). Classification of generalized seizures is simplified. No natural classification for focal seizures exists; focal seizures should be described according to their manifestations (e.g., dyscognitive, focal motor). The concepts of generalized and focal do not apply to electroclinical syndromes. Genetic, structural–metabolic, and unknown represent modified concepts to replace idiopathic, symptomatic, and cryptogenic. Not all epilepsies are recognized as electroclinical syndromes. Organization of forms of epilepsy is first by specificity: electroclinical syndromes, nonsyndromic epilepsies with structural–metabolic causes, and epilepsies of unknown cause. Further organization within these divisions can be accomplished in a flexible manner depending on purpose. Natural classes (e.g., specific underlying cause, age at onset, associated seizure type), or pragmatic groupings (e.g., epileptic encephalopathies, self‐limited electroclinical syndromes) may serve as the basis for organizing knowledge about recognized forms of epilepsy and facilitate identification of new forms.

De novo mutations in epileptic encephalopathies

Epileptic encephalopathies are a devastating group of severe childhood epilepsy disorders for which the cause is often unknown. Here we report a screen for de novo mutations in patients with two classical epileptic encephalopathies: infantile spasms (n = 149) and Lennox–Gastaut syndrome (n = 115). We sequenced the exomes of 264 probands, and their parents, and confirmed 329 de novo mutations. A likelihood analysis showed a significant excess of de novo mutations in the ∼4,000 genes that are the most intolerant to functional genetic variation in the human population (P = 2.9 × 10−3). Among these are GABRB3, with de novo mutations in four patients, and ALG13, with the same de novo mutation in two patients; both genes show clear statistical evidence of association with epileptic encephalopathy. Given the relevant site-specific mutation rates, the probabilities of these outcomes occurring by chance are P = 4.1 × 10−10 and P = 7.8 × 10−12, respectively. Other genes with de novo mutations in this cohort include CACNA1A, CHD2, FLNA, GABRA1, GRIN1, GRIN2B, HNRNPU, IQSEC2, MTOR and NEDD4L. Finally, we show that the de novo mutations observed are enriched in specific gene sets including genes regulated by the fragile X protein (P < 10−8), as has been reported previously for autism spectrum disorders.

ILAE Treatment Guidelines: Evidence‐based Analysis of Antiepileptic Drug Efficacy and Effectiveness as Initial Monotherapy for Epileptic Seizures and Syndromes

Summary:  Purpose: To assess which antiepileptic medications (AEDs) have the best evidence for long‐term efficacy or effectiveness as initial monotherapy for patients with newly diagnosed or untreated epilepsy.

Guidelines for the Evaluation and Management of Status Epilepticus

Status epilepticus (SE) treatment strategies vary substantially from one institution to another due to the lack of data to support one treatment over another. To provide guidance for the acute treatment of SE in critically ill patients, the Neurocritical Care Society organized a writing committee to evaluate the literature and develop an evidence-based and expert consensus practice guideline. Literature searches were conducted using PubMed and studies meeting the criteria established by the writing committee were evaluated. Recommendations were developed based on the literature using standardized assessment methods from the American Heart Association and Grading of Recommendations Assessment, Development, and Evaluation systems, as well as expert opinion when sufficient data were lacking.

Antiepileptic drugs—best practice guidelines for therapeutic drug monitoring: A position paper by the subcommission on therapeutic drug monitoring, ILAE Commission on Therapeutic Strategies

Although no randomized studies have demonstrated a positive impact of therapeutic drug monitoring (TDM) on clinical outcome in epilepsy, evidence from nonrandomized studies and everyday clinical experience does indicate that measuring serum concentrations of old and new generation antiepileptic drugs (AEDs) can have a valuable role in guiding patient management provided that concentrations are measured with a clear indication and are interpreted critically, taking into account the whole clinical context. Situations in which AED measurements are most likely to be of benefit include (1) when a person has attained the desired clinical outcome, to establish an individual therapeutic concentration which can be used at subsequent times to assess potential causes for a change in drug response; (2) as an aid in the diagnosis of clinical toxicity; (3) to assess compliance, particularly in patients with uncontrolled seizures or breakthrough seizures; (4) to guide dosage adjustment in situations associated with increased pharmacokinetic variability (e.g., children, the elderly, patients with associated diseases, drug formulation changes); (5) when a potentially important pharmacokinetic change is anticipated (e.g., in pregnancy, or when an interacting drug is added or removed); (6) to guide dose adjustments for AEDs with dose‐dependent pharmacokinetics, particularly phenytoin.

A double-blind, randomized trial of topiramate in Lennox–Gastaut syndrome

Objective: To evaluate the efficacy and safety of topiramate as adjunctive therapy for Lennox–Gastaut syndrome in a multicenter, double-blind, placebo-controlled trial. Background: Conventional antiepileptic drugs are frequently ineffective against multiple-seizure types of Lennox–Gastaut syndrome. Methods: Ninety-eight patients >1 year to <30 years of age, with slow spike-and-wave patterns on EEG, seizure types including drop attacks, and either a history of or active atypical absence seizures, were assigned to an 11-week, double-blind treatment phase with either topiramate or placebo. Topiramate was titrated to target doses of approximately 6 mg/kg/d. Results: For drop attacks, the most severe seizures associated with this syndrome, the median percentage reduction from baseline in average monthly seizure rate was 14.8% for the topiramate group and −5.1% (an increase) for the placebo group (p = 0.041). Topiramate-treated patients demonstrated greater improvement in seizure severity than did placebo-treated patients based on parental global evaluations (p = 0.037). The percentage of patients with a ≥50% reduction from baseline in major seizures (drop attacks and tonic-clonic seizures) was greater in the topiramate group (15/46 or 33%) than in the control group (4/50 or 8%; p = 0.002). The most common adverse events in both groups were CNS related; there were no discontinuations from topiramate therapy due to adverse events. Conclusions: Topiramate adjunctive therapy was effective in reducing the number of drop attacks and major motor seizures and in improving seizure severity as determined by parental global evaluation.

Updated ILAE evidence review of antiepileptic drug efficacy and effectiveness as initial monotherapy for epileptic seizures and syndromes

The purpose of this report was to update the 2006 International League Against Epilepsy (ILAE) report and identify the level of evidence for long‐term efficacy or effectiveness for antiepileptic drugs (AEDs) as initial monotherapy for patients with newly diagnosed or untreated epilepsy. All applicable articles from July 2005 until March 2012 were identified, evaluated, and combined with the previous analysis (Glauser et al., 2006) to provide a comprehensive update. The prior analysis methodology was utilized with three modifications: (1) the detectable noninferiority boundary approach was dropped and both failed superiority studies and prespecified noninferiority studies were analyzed using a noninferiority approach, (2) the definition of an adequate comparator was clarified and now includes an absolute minimum point estimate for efficacy/effectiveness, and (3) the relationship table between clinical trial ratings, level of evidence, and conclusions no longer includes a recommendation column to reinforce that this review of efficacy/evidence for specific seizure types does not imply treatment recommendations. This evidence review contains one clarification: The commission has determined that class I superiority studies can be designed to detect up to a 20% absolute (rather than relative) difference in the point estimate of efficacy/effectiveness between study treatment and comparator using an intent‐to‐treat analysis. Since July, 2005, three class I randomized controlled trials (RCT) and 11 class III RCTs have been published. The combined analysis (1940–2012) now includes a total of 64 RCTs (7 with class I evidence, 2 with class II evidence) and 11 meta‐analyses. New efficacy/effectiveness findings include the following: levetiracetam and zonisamide have level A evidence in adults with partial onset seizures and both ethosuximide and valproic acid have level A evidence in children with childhood absence epilepsy. There are no major changes in the level of evidence for any other subgroup. Levetiracetam and zonisamide join carbamazepine and phenytoin with level A efficacy/effectiveness evidence as initial monotherapy for adults with partial onset seizures. Although ethosuximide and valproic acid now have level A efficacy/effectiveness evidence as initial monotherapy for children with absence seizures, there continues to be an alarming lack of well designed, properly conducted epilepsy RCTs for patients with generalized seizures/epilepsies and in children in general. These findings reinforce the need for multicenter, multinational efforts to design, conduct, and analyze future clinically relevant adequately designed RCTs. When selecting a patients AED, all relevant variables and not just efficacy and effectiveness should be considered.

Rufinamide for generalized seizures associated with Lennox–Gastaut syndrome

Background: Lennox–Gastaut syndrome is a catastrophic pediatric epilepsy syndrome characterized by multiple types of treatment-resistant seizures and high rates of seizure-related injury. Current available treatments are inadequate, leaving patients with few treatment options and opportunities. Methods: We conducted a double-blind, randomized, placebo-controlled trial of the antiepileptic drug rufinamide in patients with Lennox–Gastaut syndrome. Eligible patients between 4 and 30 years of age had multiple types of seizures (including tonic–atonic and atypical absence seizures) with a minimum of 90 seizures in the month before baseline and a recent history of a slow spike-and-wave pattern on EEG. Results: After a 28-day baseline period, 139 eligible patients were randomized; 138 patients received either rufinamide (n = 74) or placebo (n = 64) in addition to their other antiepileptic drugs. The median percentage reduction in total seizure frequency was greater in the rufinamide therapy group than in the placebo group (32.7% vs 11.7%, p = 0.0015). There was a difference (p < 0.0001) in tonic–atonic (“drop attack”) seizure frequency with rufinamide (42.5% median percentage reduction) vs placebo (1.4% increase). The rufinamide group had a greater improvement in seizure severity (p = 0.0041) and a higher 50% responder rate compared with placebo for total seizures (p = 0.0045) and tonic–atonic seizures (p = 0.002). The common adverse events (reported by ≥10% of patients receiving rufinamide) were somnolence (24.3% with rufinamide vs 12.5% with placebo) and vomiting (21.6% vs 6.3%). Conclusions: Rufinamide was an effective and well-tolerated treatment for seizures associated with Lennox–Gastaut syndrome.

Brain magnetic resonance imaging abnormalities after the Norwood procedure using regional cerebral perfusion

OBJECTIVES Neurologic deficits are common after the Norwood procedure for hypoplastic left heart syndrome. Because of the association of deep hypothermic circulatory arrest with adverse neurologic outcome, regional low-flow cerebral perfusion has been used to limit the period of intraoperative brain ischemia. To evaluate the impact of this technique on brain ischemia, we performed serial brain magnetic resonance imaging in a cohort of infants before and after the Norwood operation using regional cerebral perfusion. METHODS Twenty-two term neonates with hypoplastic left heart syndrome were studied with brain magnetic resonance imaging before and at a median of 9.5 days after the Norwood operation. Results were compared with preoperative, intraoperative, and postoperative risk factors to identify predictors of neurologic injury. RESULTS Preoperative magnetic resonance imaging (n = 22) demonstrated ischemic lesions in 23% of patients. Postoperative magnetic resonance imaging (n = 15) demonstrated new or worsened ischemic lesions in 73% of patients, with periventricular leukomalacia and focal ischemic lesions occurring most commonly. Prolonged low postoperative cerebral oximetry (<45% for >180 minutes) was associated with the development of new or worsened ischemia on postoperative magnetic resonance imaging (P = .029). CONCLUSIONS Ischemic lesions occur commonly in neonates with hypoplastic left heart syndrome before surgery. Despite the adoption of regional cerebral perfusion, postoperative cerebral ischemic lesions are frequent, occurring in the majority of infants after the Norwood operation. Long-term follow-up is necessary to assess the functional impact of these lesions.

A double-blind, randomized trial of topiramate as adjunctive therapy for partial-onset seizures in children

Objective: To evaluate the efficacy and safety of topiramate 6 mg/kg/day in children (age 2 to 16 years) as adjunctive therapy for uncontrolled partial-onset seizures with or without secondarily generalized seizures in a multicenter, randomized, double-blind, placebo-controlled trial. Methods: Patients with at least six partial-onset seizures during the 8-week baseline phase were treated with either topiramate (n = 41) or placebo (n = 45) for 16 weeks. Results: Topiramate-treated patients had a greater median percent reduction from baseline in average monthly partial-onset seizure rate than placebo-treated patients (33.1% versus 10.5%, p = 0.034), a greater proportion of treatment responders (i.e., patients with a ≥50% seizure rate reduction; 16 of 41 [39%] versus 9 of 45 [20%], p = 0.080), and patients with a ≥75% seizure rate reduction (7 of 41 [17%] versus 1 of 45 [2%], p = 0.019), and better parental global evaluations of improvement in seizure severity (p = 0.019). Emotional lability (12% versus 4%), fatigue (15% versus 7%), difficulty with concentration or attention (12% versus 2%), and forgetfulness/impaired memory (7% versus 0%) were more frequent among topiramate-treated than placebo-treated patients. Most treatment-emergent adverse events were mild or moderate in severity. No topiramate-treated patients discontinued the study due to adverse events. Conclusions: Topiramate was safe and effective in the treatment of partial-onset seizures in children.