Refractory and Super-refractory Status Epilepticus

Relationship between continuous EEG monitoring findings and prognostic factors in patients with status epilepticus

BACKGROUND AND PURPOSE

Little information is available regarding the use of continuous electroencephalography (cEEG) monitoring findings to predict the prognosis of patients with status epilepticus, which could aid in prognostication. This study investigated the relationship between cEEG monitoring findings and various prognostic indicators in patients with status epilepticus.

METHODS

We reviewed the clinical profiles and cEEG monitoring data of 28 patients with status epilepticus over a ten-year period. Patient demographics, etiology, EEG features, duration of hospital stay, number of antiseizure medications, and outcome measures were analyzed. Functional outcomes were assessed using the modified Rankin Scale (mRS), which evaluates the degree of daily living impairment and dependence on others resulting from neurological injury.

RESULTS

Patients exhibiting electrographic status epilepticus (ESE) demonstrated significantly longer duration of status epilepticus (77.75 ± 58.25 vs. 39.86 ± 29.81 h, p = 0.024) and total length of hospital stay (13.00 ± 6.14 vs. 8.14 ± 5.66 days, p = 0.038) when compared to those with ictal-interictal continuum (IIC). Individuals who displayed any increase in modified Rankin Scale (mRS) score between their premorbid state and discharge also had significantly longer duration of status epilepticus (74.09 ± 34.94 vs. 51.56 ± 54.25 h, p = 0.041) and total length of hospital stay (15.89 ± 6.05 vs. 8.05 ± 4.80 days, p = 0.004) when compared to those who showed no difference. The most prevalent etiology of status epilepticus in our study was chronic structural brain lesions.

CONCLUSIONS

This suggests that ESE may serve as a predictor of prolonged duration of status epilepticus and increased hospitalization among patients with status epilepticus.

Use of perampanel oral suspension for the treatment of refractory and super-refractory status epilepticus

INTRODUCTION

Status epilepticus (SE) is a medical emergency associated with a significant risk of disability and death. The treatment of SE follows a step-wise approach, with limited data on ideal antiseizure medications (ASMs) for refractory and super refractory SE (RSE/SRSE). Perampanel (PER), an AMPA receptor antagonist, has shown promise in animal models but still has limited data in humans. This study tried to evaluate optimal dosage and safety of PER in RSE and SRSE patients.

MATERIALS AND METHODS

We retrospectively analysed 17 adult patients with RSE (1) or SRSE (16) treated with PER. Demographic and clinical data, including EEG patterns, ASMs administered, PER dosages, and PER plasma concentrations, were collected. For patients receiving a 24 mg PER loading dose (full dose group), the following treatment regimen was applied: 24 mg per day for 48 h following by 16 mg per day. The response to PER was assessed based on electroencephalographic (EEG) improvement from high to low epileptiform activity or from low to the absence of epileptiform activities. Safety was evaluated monitoring hepatic and renal function.

RESULTS

A response rate of 58.82 % was observed, with significantly higher responses in the full dose group (81.82 %) compared to those receiving PER doses below 24 mg (low dose group) (16.67 %) (p-value = 0.004; OR 0.044, 95 % CI 0.003 to 0.621, p = 0.021). No other clinical factors significantly influenced treatment response. Hepatic enzymes become elevated in most patients (70.59 %) but spontaneously decreased.

DISCUSSION

Our findings suggest that a 24 mg PER dose administered for 48 h may be more effective in managing RSE and SRSE compared to doses below 24 mg, potentially due to pharmacokinetic factors.

CONCLUSION

More robust data on PER in RSE and SRSE, including standardized dosing procedures and plasma level monitoring are needed. PER's potential benefits should be explored further, particularly in patients with RSE and SRSE.

Early versus late switch over of antiseizure medications from intravenous to the oral route in children with seizures: Single-blinded, randomized controlled trial (ELAIO trial)

INTRODUCTION

Early switch-over of anti-seizure medications (ASMs) from intravenous to oral route may reduce the duration of hospitalization, drug acquisition costs, and behavioral upset in hospitalized children with seizures.

OBJECTIVE

The primary objective was to compare short-term seizure recurrence within 1 week in hospitalized children aged 1 month to 18 years with new-onset/breakthrough seizures after an early versus late switch-over from intravenous to the oral route of ASMs. Secondary objectives were to compare the incidence of status epilepticus, duration of hospital stay, drug acquisition costs, and caregiver-reported satisfaction scores in both groups.

METHODS

In this single-blind randomized controlled trial, patients with seizures were categorized based on the number of ASMs required and the history of status epilepticus. Patients in each category were randomized in a 1:1 ratio into either early or late switch-over (ES or LS) groups. In the ES groups, ASMs were tapered one-by-one between 0 and 24 hours of seizure freedom, while in the LS groups, they were tapered one-by-one between 24 and 48 hours of seizure freedom.

RESULTS

A total of 112 children were enrolled in the study, with 56 in each arm. Seizure recurrence at 1 week and 12 weeks was comparable in ES and LS groups (3/55 vs. 1/54 at 1 week, p=0.61; 7/49 vs. 6/49 at 12 weeks, p=0.98). Drug acquisition costs were significantly lower in the ES group (393±274 vs. 658±568 INR, p=0.002). Thrombophlebitis and dysphoria were significantly more common in the LS group (p=0.008 and 0.03, respectively).

CONCLUSION

The early switch-over of ASMs from intravenous to oral route is safe without any significant increased risk of short-term seizure recurrence and also associated with a reduction in the incidence of thrombophlebitis and ASM acquisition costs.

TRIAL REGISTRATION NO

CTRI/2021/03/032145.

Investigating the genetic contribution in febrile infection-related epilepsy syndrome and refractory status epilepticus

Introduction

Febrile infection-related epilepsy syndrome (FIRES) is a severe childhood epilepsy with refractory status epilepticus after a typically mild febrile infection. The etiology of FIRES is largely unknown, and outcomes in most individuals with FIRES are poor.

Methods

Here, we reviewed the current state-of-the art genetic testing strategies in individuals with FIRES. We performed a systematic computational analysis to identify individuals with FIRES and characterize the clinical landscape using the Electronic Medical Records (EMR). Among 25 individuals with a confirmed FIRES diagnosis over the last decade, we performed a comprehensive review of genetic testing and other diagnostic testing.

Results

Management included use of steroids and intravenous immunoglobulin (IVIG) in most individuals, with an increased use of immunomodulatory agents, including IVIG, plasma exchange (PLEX) and immunosuppressants such as cytokine inhibitors, and the ketogenic diet after 2014. Genetic testing was performed on a clinical basis in almost all individuals and was non-diagnostic in all patients. We compared FIRES with both status epilepticus (SE) and refractory status epilepticus (RSE) as a broader comparison cohort and identified genetic causes in 36% of patients with RSE. The difference in genetic signatures between FIRES and RSE suggest distinct underlying etiologies. In summary, despite the absence of any identifiable etiologies in FIRES, we performed an unbiased analysis of the clinical landscape, identifying a heterogeneous range of treatment strategies and characterized real-world clinical practice.

Discussion

FIRES remains one of the most enigmatic conditions in child neurology without any known etiologies to date despite significant efforts in the field, suggesting a clear need for further studies and novel diagnostic and treatment approaches.

The Frequency of Refractory Status Epilepticus and Its Outcome in a Tertiary Care Hospital in Pakistan: A Retrospective Study

Background

Refractory status epilepticus (RSE) is a common neurologic emergency with refractory cases leading to increased rates of morbidity and mortality in patients. The lack of previous studies on the incidence, causes, and management of refractory status epilepticus in the pediatric population from our region prompted us to investigate further in this study.

Methods

We included retrospective data of all patients admitted to the pediatric intensive care unit (PICU) with a provisional diagnosis of RSE at a tertiary care hospital in Karachi from February 2019 to February 2021. No personal identification data was used, and confidentiality of the data was maintained throughout the analysis. The Statistical Package for the Social Sciences (SPSS) software version 22.0 (IBM SPSS Statistics, Armonk, NY, USA) was used to pool data and perform a descriptive analysis.

Results

Among the 687 patients who presented to the PICU with seizures, 50 (7.27%) patients were eventually diagnosed with RSE during the two-year period. The majority of the patients were male and less than one year of age. Infectious causes predominated our data cohort, and a four-drug regimen consisting of phenytoin, levetiracetam, valproic acid, and midazolam was able to terminate RSE in the majority of the patients in our setting (70%). The mortality rate was noted to be 22% among patients with RSE.

Conclusion

Morbidity and mortality among pediatric RSE patients are high in our settings. Urgent emergency services and timely cause-directed intervention could improve outcomes.

Fenfluramine: A Review of Pharmacology, Clinical Efficacy, and Safety in Epilepsy

Despite the availability of more than 30 antiseizure medications (ASMs), the proportion of patients who remain refractory to ASMs remains static. Refractory seizures are almost universal in patients with epileptic encephalopathies. Since many of these patients are not candidates for curative surgery, there is always a need for newer ASMs with better efficacy and safety profile. Recently, the anti-obesity medication fenfluramine (FFA) has been successfully repurposed, and various regulatory agencies approved it for seizures associated with Dravet and Lennox–Gastaut syndromes. However, there is a limited in-depth critical review of FFA to facilitate its optimal use in a clinical context. This narrative review discusses and summarizes the antiseizure mechanism of action of FFA, clinical pharmacology, and clinical studies related to epilepsy, focusing on efficacy and adverse effects.

Pharmacotherapeutic management of seizures in patients with Angleman syndrome

Approximately 80-90% of patients with Angelman syndrome (AS) develop childhood-onset intractable seizures with major negative impact on the quality of life.Thus adequate management of seizures is the most critical priority to improve health-related quality of life in children with AS.

AREAS COVERED

The primary focus of the review is on pharmacotherapeutic management of seizures. The first part of the review briefly discusses epileptogenesis and polymorphic seizure phenotypes associated with AS to understand pharmacotherapeutic decision-making better. Next, the review explores individual antiseizure medicines (ASMs) and their potential therapeutic utility. Lastly, some future and emerging treatment options are discussed that can transform the management of seizures in patients with AS.

EXPERT OPINION

Evidence for treating seizures in AS mainly derives from low-quality studies. Levetiracetam and clobazam are the most commonly used ASMs. Although the potential utility of several other ASMs(valproate, topiramate, lamotrigine, ethosuximide, clonazepam) has been well documented for some time, the treatment landscape may rapidly evolve due to the availability of newer and better tolerated ASMs(cannabidiol oil, brivaracetam, perampanel). In addition, a better understanding of the underlying pathogenesis and the development of molecular therapeutics offer hope for precision therapies for seizures.

Good seizure outcome after focal resection surgery for super-refractory status epilepticus: Report of two cases

Background:

There is scarce evidence regarding focal resection surgery for super-refractory status epilepticus (SRSE), which is resistant to general anesthetic treatment over 24 h. We report two patients with SRSE, in whom good seizure outcomes were obtained following focal resection surgery.

Case Description:

Patient 1: A 58-year-old man who underwent left anterior temporal lobectomy with hippocampectomy at the age of 38 years after being diagnosed left medial temporal lobe epilepsy. After 19 years of surgery with no epileptic attacks, the patient developed SRSE. Electroencephalogram (EEG) demonstrated persistence of lateralized periodic discharges in the left frontotemporal region. On the 20^th day after SRSE onset, resection of the frontal lobe and temporal lobe posterior to the resection cavity was performed. Patient 2: A 62-year-old man underwent craniotomy for anaplastic astrocytoma in the left frontal lobe at the age of 34 years. Since the age of 60 years, he developed SRSE 3 times over 1 and 1/12 years. On EEG, repeated ictal discharges were observed at the medial part of the left frontal region during the three SRSEs. Corresponding to the ictal EEG findings, high signals on diffusion-weighted magnetic resonance images and focal hypermetabolism on fluorodeoxyglucose-positron emission tomography were observed around the supplementary motor area, medial to the resection cavity. Resection surgery of the area was performed during the interictal period.

Conclusion:

Good seizure outcome was obtained in the two cases which provide additional support for the recent concept of focal resection surgery as an indication for SRSE.

Rescue therapies for seizure emergencies: current and future landscape

INTRODUCTION

Seizure emergencies-status epilepticus and seizure clusters-require rapid evaluation and treatment. Several consensus-based guidelines support a prompt use of intravenous benzodiazepines as the first-line therapy in seizure emergencies. However, most seizure emergencies start outside the hospital settings. Until recently, approved prehospital rescue therapies were limited to rectal diazepam and buccal midazolam (Europe only).

METHODS

The author provides a narrative review of rescue therapies for seizure emergencies based on a comprehensive literature review (PubMed and OvidSP vendors with appropriate keywords to incorporate recent evidence) to highlight the changing landscape of seizure recue therapies.

RESULTS

A commercial version of intranasal midazolam was approved by the FDA in 2019 for 12 ≥ years old with seizure clusters. In 2020, the FDA also approved a proprietary vitamin E solution-based diazepam nose spray to abort seizure clusters in ≥ 6 years old subjects. Other than these two new options, the author discussed two previously approved therapies: rectal diazepam and buccal midazolam. The review also includes the use of intramuscular diazepam and midazolam, clonazepam wafer, sublingual and intranasal lorazepam in seizure emergencies. Besides the availability of new therapies from successful trials in controlled settings, the real-world challenges of using rescue medicines in community settings are slowly emerging.

DISCUSSION

With multiple options, a more robust and updated cost-effective analysis of different rescue medicines needs to be performed using effectiveness data from the literature and cost data from publicly available market prices. Further research is also ongoing to develop alternative non-intravenous treatment options for outpatient settings. Lastly, several other non-benzodiazepine drugs, such as allopregnanolone, propofol, and brivaracetam, are also currently under development for seizure emergencies.

An Insight into the Current Understanding of Status Epilepticus: From Concept to Management

Status epilepticus (SE), a subset of epilepsy, represents a debilitating neurological disorder often associated with alarming mortality and morbidity numbers. Even though SE is one of the extensively researched topics with conspicuous data available in the literature, a scientific gap exists in understanding the heterogeneous facets of the disorder like occurrence, definition, classification, causes, molecular mechanisms, etc., thereby providing a defined management program. Cognizance of this heterogeneity and scientific limitation with its subsequent correlation to the recent advancements in medical and scientific domains would serve not only in bridging the gap but also in developing holistic and prompt management programs. Keeping this as an objective, an extensive literature survey was performed during this study, and key findings have been shared. The present study provides a semantic and perspective synopsis toward acknowledging the diversified nature of SE and its variants with respect to their definition, classification, etiology, diagnosis, and management.

Evaluation and Management of Seizures and Status Epilepticus

Seizures are frequently triggered by an inciting event and result from uninhibited excitation and/or decreased inhibition of a pool of neurons. If physiologic seizure abortive mechanisms fail, the ensuing unrestrained synchronization of neurons-status epilepticus-can be life-threatening and is associated with the potential for marked morbidity in survivors and high medical care costs. Prognosis is intimately related to etiology and its response to therapeutic measures. Timely implementation of pharmacologic therapy while concurrently performing a stepwise workup for etiology are paramount. Neurodiagnostic testing should guide titration of pharmacologic therapies, and help determine if there is a role for immune modulation.

Recent Advances in the Diagnosis and Treatment of Neonatal Seizures

Seizures are the most common neurological emergency in the neonates, and this age group has the highest incidence of seizures compared with any other period of life. The author provides a narrative review of recent advances in the genetics of neonatal epilepsies, new neonatal seizure classification system, diagnostics, and treatment of neonatal seizures based on a comprehensive literature review (MEDLINE using PubMED and OvidSP vendors with appropriate keywords to incorporate recent evidence), personal practice, and experience. Knowledge regarding various systemic and postzygotic genetic mutations responsible for neonatal epilepsy has been exploded in recent times, as well as better delineation of clinical phenotypes associated with rare neonatal epilepsies. An International League Against Epilepsy task force on neonatal seizure has proposed a new neonatal seizure classification system and also evaluated the specificity of semiological features related to particular etiology. Although continuous video electroencephalogram (EEG) is the gold standard for monitoring neonatal seizures, amplitude-integrated EEGs have gained significant popularity in resource-limited settings. There is tremendous progress in the automated seizure detection algorithm, including the availability of a fully convolutional neural network using artificial machine learning (deep learning). There is a substantial need for ongoing research and clinical trials to understand optimal medication selection (first line, second line, and third line) for neonatal seizures, treatment duration of antiepileptic drugs after cessation of seizures, and strategies to improve neuromorbidities such as cerebral palsy, epilepsy, and developmental impairments. Although in recent times, levetiracetam use has been significantly increased for neonatal seizures, a multicenter, randomized, blinded, controlled phase IIb trial confirmed the superiority of phenobarbital over levetiracetam in the acute suppression of neonatal seizures. While there is no single best choice available for the management of neonatal seizures, institutional guidelines should be formed based on a consensus of local experts to mitigate wide variability in the treatment and to facilitate early diagnosis and treatment.

Electroconvulsive Therapy in Super Refractory Status Epilepticus: Case Series with a Defined Protocol

Super-refractory status epilepticus (SRSE) represents a neurological emergency that is characterized by a lack of response to the third line of antiepileptic treatment, including intravenous general anesthetics. It is a medical challenge with high morbidity and mortality. Electroconvulsive therapy (ECT) has been recommended as a nonpharmacologic option of treatment after other alternatives are unsuccessful. Its effect on the cessation of SRSE has been minimally investigated. The objective of this article is to analyze the effect of ECT on SRSE. For this purpose, a multidisciplinary team created a protocol based on clinical guidelines similar to those described previously by Ray et al. (2017). ECT was applied to six patients with SRSE after the failure of antiepileptic treatment and pharmacologic coma.The objective of each ECT session was to elicit a motor seizure for at least 20 s. SRSE was resolved in all patients after several days of treatment, including ECT as a therapy, without relevant adverse effects. Thus, ECT is an effective and feasible option in the treatment of SRSE, and its place in the algorithm in treatment should be studied due to the uncommon adverse effects and the noninvasive character of the therapy.