Acute Symptomatic Seizures: A Clinically Oriented Review

A Comprehensive Review of Recent Trends in Surgical Approaches for Epilepsy Management

Epilepsy is a neurological disorder that affects millions of people worldwide, with a significant proportion of patients experiencing drug-resistant epilepsy, where seizures remain uncontrolled despite medical treatment. This review evaluates the latest surgical techniques for managing epilepsy, focusing on their effectiveness, safety, and the ongoing challenges that hinder their broader adoption. We explored various databases including PubMed, Google Scholar, and Cochrane Library to look for relevant literature using the following keywords: Epilepsy, Resective Surgery, Corpus Collectumy, and Antiepileptic Drugs. A total of 54 relevant articles were found and thoroughly explored. Recent advancements in surgical interventions include resective procedures such as anterior temporal lobectomy, corpus callosotomy, and hemispherectomy, which have been particularly effective in reducing seizures for specific types of epilepsy. Minimally invasive techniques, including laser interstitial thermal therapy and focused ultrasound, are increasingly being used, offering promising outcomes for certain patient groups. Additionally, neuromodulation methods such as deep brain stimulation, vagus nerve stimulation, and responsive neurostimulation provide alternative treatment options, especially for patients who are not suitable candidates for resective surgery. Despite these advancements, the full potential of epilepsy surgery is often underutilized due to various challenges. Inconsistent referral practices, a lack of standardized surgical protocols, and significant socioeconomic barriers continue to limit access to these procedures. Addressing these issues through improved referral processes, better education for healthcare providers and patients, and ensuring equitable access to advanced surgical treatments is crucial for optimizing patient outcomes. Future research should focus on overcoming these barriers and assessing long-term outcomes to further enhance the care of patients with epilepsy.

Characteristics of Stroke-related Seizures and their Predictive Factors: A Tertiary Care Center Experience

BACKGROUND AND PURPOSE

Various risk factors have been described in the literature that increase the risk of seizures associated with stroke. This study was aimed to determine the occurrence rate of poststroke seizures (PSSs) and the associated risk factors in Arab population.

MATERIALS AND METHODS

Study included all stroke patients aged >18 years with a minimum follow-up of 24 months following stroke to identify seizure occurrence. Patient's hospital records for all admissions and clinic visits were reviewed. Seizures were classified into early PSS if they occur within 1 week of stroke, and late PSS if they occur after 1 week of stroke.

RESULTS

Out of 594 patients, 380 were males. Seizure occurrence was higher in anterior circulation infarctions (94.8%, P < 0.05), cortical location (80.5%, P < 0.05), large artery atherosclerosis (63.8%, P < 0.05), lower activated partial thromboplastin time (APTT) (P = 0.0007), patients with ischemic heart disease (IHD) (P = 0.01), and those who underwent craniotomy (P = 0.001). Nonhigh-density lipoprotein cholesterol was inversely related to PSS (P = 0.01). Higher stroke severity (89%) and confusion (67%) at the time of presentation were independently related to PSS.

CONCLUSIONS

Eighty-two (13.8%) patients had PSS. Greater stroke severity at presentation with altered sensorium was independent risk factors for the development of PSS. Patients with underlying IHD, lower APTT, and undergoing neurosurgical intervention require vigilant monitoring for PSS.

Clinical approaches for poststroke seizure: a review

Poststroke seizure is a potential complication of stroke, which is the most frequent acute symptomatic seizure in adults. Patients with stroke may present with an abnormal or aggressive behavior accompanied by altered mental status and symptoms, such as hemiparesis, dysarthria, and sensory deficits. Although stroke manifestations that mimic seizures are rare, diagnosing poststroke seizures can be challenging when accompanied with negative postictal symptoms. Differential diagnoses of poststroke seizures include movement disorders, syncope, and functional (nonepileptic) seizures, which may present with symptoms similar to seizures. Furthermore, it is important to determine whether poststroke seizures occur early or late. Seizures occurring within and after 7 d of stroke onset were classified as early and late seizures, respectively. Early seizures have the same clinical course as acute symptomatic seizures; they rarely recur or require long-term antiseizure medication. Conversely, late seizures are associated with a risk of recurrence similar to that of unprovoked seizures in a patient with a focal lesion, thereby requiring long-term administration of antiseizure medication. After diagnosis, concerns regarding treatment strategies, treatment duration, and administration of primary and secondary prophylaxis often arise. Antiseizure medication decisions for the initiation of short-term primary and long-term secondary seizure prophylaxis should be considered for patients with stroke. Antiseizure drugs such as lamotrigine, carbamazepine, lacosamide, levetiracetam, phenytoin, and valproate may be administered. Poststroke seizures should be diagnosed systematically through history with differential diagnosis; in addition, classifying them as early or late seizures can help to determine treatment strategies.

Inherent seizure susceptibility in patients with antihistamine-induced acute symptomatic seizure: a resting-state EEG analysis

We compared neural activities and network properties between the antihistamine-induced seizures (AIS) and seizure-free groups, with the hypothesis that patients with AIS might have inherently increased neural activities and network properties that are easily synchronized. Resting-state electroencephalography (EEG) data were collected from 27 AIS patients and 30 healthy adults who had never had a seizure. Power spectral density analysis was used to compare neural activities in each localized region. Functional connectivity (FC) was measured using coherence, and graph theoretical analyses were performed to compare network properties between the groups. Machine learning algorithms were applied using measurements found to be different between the groups in the EEG analyses as input features. Compared with the seizure-free group, the AIS group showed a higher spectral power in the entire regions of the delta, theta, and beta bands, as well as in the frontal areas of the alpha band. The AIS group had a higher overall FC strength, as well as a shorter characteristic path length in the theta band and higher global efficiency, local efficiency, and clustering coefficient in the beta band than the seizure-free group. The Support Vector Machine, k-Nearest Neighbor, and Random Forest models distinguished the AIS group from the seizure-free group with a high accuracy of more than 99%. The AIS group had seizure susceptibility considering both regional neural activities and functional network properties. Our findings provide insights into the underlying pathophysiological mechanisms of AIS and may be useful for the differential diagnosis of new-onset seizures in the clinical setting.

Clinical impact of carbapenems in critically ill patients with valproic acid therapy: A propensity-matched analysis

Background

Valproic acid (VPA) is one of the most widely used broad-spectrum antiepileptic drugs, and carbapenems (CBPs) remain the drug of choice for severe infection caused by multidrug-resistant bacteria in critically ill patients. The interaction between VPA and CBPs can lead to a rapid depletion of serum VPA level. This may then cause status epilepticus (SE), which is associated with significant mortality. However, the prognostic impact of drug interactions in critically ill patients remains an under-investigated issue.

Objective

The aim of this study was to compare the prognosis of critically ill patients treated with VPA and concomitant CBPs or other broad-spectrum antibiotics.

Methods

Adult patients admitted to a medical center intensive care unit between January 2007 and December 2017 who concomitantly received VPA and antibiotics were enrolled. The risk of reduced VPA serum concentration, seizures and SE, mortality rate, length of hospital stay (LOS), and healthcare expenditure after concomitant administration were analyzed after propensity score matching.

Results

A total of 1,277 patients were included in the study, of whom 264 (20.7%) concomitantly received VPA and CBPs. After matching, the patients who received CBPs were associated with lower VPA serum concentration (15.8 vs. 60.8 mg/L; p &lt; 0.0001), a higher risk of seizures (51.2 vs. 32.4%; adjusted odds ratio [aOR], 2.19; 95% CI, 1.48–3.24; p &lt; 0.0001), higher risk of SE (13.6 vs. 4.7%; aOR, 3.20; 95% CI, 1.51–6.74; p = 0.0014), higher in-hospital mortality rate (33.8 vs. 24.9%; aOR, 1.57; 95% CI, 1.03–2.20; p = 0.036), longer LOS after concomitant therapy (41 vs. 30 days; p &lt; 0.001), and increased healthcare expenditure (US$20,970 vs. US$12,848; p &lt; 0.0001) than those who received other broad-spectrum antibiotics.

Conclusion

The administration of CBPs in epileptic patients under VPA therapy was associated with lower VAP serum concentration, a higher risk of seizures and SE, mortality, longer LOS, and significant utilization of healthcare resources. Healthcare professionals should pay attention to the concomitant use of VPA and CBPs when treating patients with epilepsy. Further studies are warranted to investigate the reason for the poor outcomes and whether avoiding the co-administration of VPA and CBP can improve the outcomes of epileptic patients.

Seizures in adults with suspected central nervous system infection

Background

Seizures can be part of the clinical presentation of central nervous system (CNS) infections. We describe patients suspected of a neurological infection who present with a seizure and study diagnostic accuracy of clinical and laboratory features predictive of CNS infection in this population.

Methods

We analyzed all consecutive patients presenting with a seizure from two prospective Dutch cohort studies, in which patients were included who underwent cerebrospinal fluid (CSF) examination because of the suspicion of a CNS infection.

Results

Of 900 episodes of suspected CNS infection, 124 (14%) presented with a seizure. The median age in these 124 episodes was 60 years (IQR 45–71) and 53% of patients was female. CSF examination showed a leukocyte count ≥ 5/mm³ in 41% of episodes. A CNS infection was diagnosed in 27 of 124 episodes (22%), a CNS inflammatory disorder in 8 (6%) episodes, a systemic infection in 10 (8%), other neurological disease in 77 (62%) and in 2 (2%) episodes another systemic disease was diagnosed. Diagnostic accuracy of clinical and laboratory characteristics for the diagnosis of CNS infection in this population was low. CSF leukocyte count was the best predictor for CNS infection in patients with suspected CNS infection presenting with a seizure (area under the curve 0.94, [95% CI 0.88 – 1.00]).

Conclusions

Clinical and laboratory features fail to distinguish CNS infections from other causes of seizures in patients with a suspected CNS infection. CSF leukocyte count is the best predictor for the diagnosis of CNS infection in this population.

Acute Provoked Seizures-Work-Up and Management in Adults

Acute provoked seizures, also known as acute symptomatic seizures, occur secondary to a neurological or systemic precipitant, commonly presenting as a first-time seizure. In this article, we will discuss etiology, emergent protocols, medical work-up, initial treatment, and management of these seizures. The definitions, classifications, and management of convulsive status epilepticus and nonconvulsive status epilepticus in an acute setting will also be reviewed.

Seizures and epilepsy secondary to viral infection in the central nervous system

Viral infection in the central nervous system (CNS) is a common cause of seizures and epilepsy. Acute symptomatic seizures can occur in the context of almost all types of acute CNS viral infection. However, late unprovoked seizures and epilepsy may not be frequent after viral infection of the CNS. The incidence of seizures and epilepsy after CNS viral infection is mainly dependent on the brain region of infection. It remains to be determined whether treatment of CNS viral infection using antiepileptic drugs (AEDs) can prevent seizures and subsequent epilepsy in patients, particularly with regard to the timing, drug choice and dosage, and duration of AEDs. The postoperative outcome of seizures in patients with intractable epilepsy caused by viral encephalitis primarily depends on the epileptogenic zone. In addition, neuroinflammation is known to be widely involved in the generation of seizures during CNS viral infection, and the effects of anti-inflammatory therapies in preventing seizures and epilepsy secondary to CNS viral infection require further studies. In this review, we discuss the incidence, mechanisms, clinical management and prognosis of seizures and epilepsy secondary to CNS viral infection, and summarize common CNS viral infections that cause seizures and epilepsy.

Acute Focal Seizures Start As Local Synchronizations of Neuronal Ensembles

Understanding seizure formation and spread remains a critical goal of epilepsy research. We used fast in vivo two-photon calcium imaging in male mouse neocortex to reconstruct, with single-cell resolution, the dynamics of acute (4-aminopyridine) focal cortical seizures as they originate within a spatially confined seizure initiation site (intrafocal region), and subsequently propagate into neighboring cortical areas (extrafocal region). We find that seizures originate as local neuronal ensembles within the initiation site. This abnormal hyperactivity engages increasingly larger areas in a saltatory fashion until it breaks into neighboring cortex, where it proceeds smoothly and is then detected electrophysiologically (LFP). Interestingly, PV inhibitory interneurons have spatially heterogeneous activity in intrafocal and extrafocal territories, ruling out a simple role of inhibition in seizure formation and spread. We propose a two-step model for the progression of focal seizures, where neuronal ensembles activate first, generating a microseizure, followed by widespread neural activation in a traveling wave through neighboring cortex during macroseizures.SIGNIFICANCE STATEMENT We have used calcium imaging in mouse sensory cortex in vivo to reconstruct the onset of focal seizures elicited by local injection of the chemoconvulsant 4-aminopyridine. We demonstrate at cellular resolution that acute focal seizures originate as increasingly synchronized local neuronal ensembles. Because of its spatial confinement, this process may at first be undetectable even by nearby LFP electrodes. Further, we establish spatial footprints of local neural subtype activity that correspond to consecutive steps of seizure microprogression. Such footprints could facilitate determining the recording location (e.g., inside/outside an epileptogenic focus) in high-resolution studies, even in the absence of a priori knowledge about where exactly a seizure started.

Seizure and status epilepticus in chronic subdural hematoma

BACKGROUND

Acute symptomatic seizure (ASz) and status epilepticus (SE) are serious conditions associated with poor quality of life, with unfavorable psychosocial and functional outcome. Chronic subdural hematoma (cSDH) is a common neurosurgical disease related to those complications; therefore, we aimed to evaluate incidence, predictors of ASz/SE, and outcome in this cohort.

METHODS

We retrospectively analyzed patient diagnosed cSDH between 2010 and 2017. Beside their incidence of ASz/SE, patient characteristics, symptoms at admission, comorbidities, and all previously published relevant parameters were assessed. Recurrence rate and functional outcome were analyzed at hospital discharge and 90-day follow-up.

RESULTS

A total of 375 patients were included; incidence of ASz was 15.2% and of SE, 1.9%. In the univariate analysis, drainage insertion (P =  0.004; OR = 0.3) was a significant negative predictor for ASz/SE and multivariate analysis, including all significant parameters, designated GCS ≤13 at admission (P = 0.09; OR = 1.9), remote stroke (P = 0.009; OR = 2.9), and recurrence rate within 14 days (P = 0.001; OR = 3.3; with an incidence of 13%) as independent predictors for ASz/SE. Overall, patients with ASz/SE had significantly unfavorable outcome at discharge (54.7%; P < 0.001) and follow-up (39.5%; P < 0.001) with only slight improvement. Late seizures occurred in 3.8% within follow-up period. Any patient with SE had an unfavorable outcome at discharge without any improvement at follow-up having a mortality rate of 14.2%.

CONCLUSION

Independent predictors for ASz/SE are GCS ≤13 at admission, remote stroke, and recurrent hematoma in patients with cSDH, which is associated with worse functional outcome, particularly those with SE. Due to the higher rate of seizures than recurrence rate, a routine pre- and postoperative EEG besides CT is recommended.

Neuron specific enolase as a marker of seizure related neuronal injury

BACKGROUND

and purpose: Neuron specific enolase (NSE) is an established biomarker of neuronal damage. It is not clear how much seizures contribute to the neuronal damage, morbidity or mortality in critically ill neurology patients. The aim of this study is to determine the impact of seizures on neuronal injury in critically ill neurology patients by using neuron specific enolase as a biomarker.

MATERIAL AND METHODS

Forty patients with clinical evidence of acute central nervous system disease associated with seizures were included as critically ill neurology patients with seizures [CINPS] (age in years 38.8 ± 17.54, mean ± SD; 22 males) and 43 age and sex-matched acute central nervous system disease without seizures were recruited as critically ill neurology patients [CINP] (age in years 37.84 ± 17.38 years mean ± SD; 24 males) The serum NSE assays were performed in CINPS (within 24 h of last seizure) and in CINP using an enzyme immunoassay kit.

RESULTS

The level of serum neuron specific enolase was significantly higher in CINP with seizures compared to those without seizures. The length of ICU stay was more prolonged in those with seizures. There was a close correlation between the NSE levels and frequency of seizures. There was no significant difference in the mortality between both the groups.

CONCLUSIONS

NSE a marker of neuronal injury was elevated in patients with acute central nervous system diseases. It is significantly higher in patients with seizures in comparison to those without seizures. This warrants further studies to document aggressive treatment of seizures in acute neurologically ill patients can reduce neuronal damage.

Poststroke epilepsy: current perspectives on diagnosis and treatment

Seizures and epilepsy are quite a common outcome of arterial ischemic stroke (AIS) both in pediatric and adult patients, with distinctly higher occurrence in children. These poststroke consequences affect patients' lives, often causing disability. Poststroke seizure (PSS) may also increase mortality in patients with AIS. Early PSS (EPSS) occurring up to 7 days after AIS, late PSS (LPSS) occurring up to 2 years after the onset of AIS, as well as poststroke epilepsy (PSE) can be distinguished. However, the exact definition and cutoff point for PSE should be determined. A wide range of risk factors for seizures and epilepsy after AIS are still being detected and analyzed. More accurate knowledge on risk factors for PSS and PSE as well as possible prediction of epileptic seizures after the onset of AIS may have an impact on improving the prevention and treatment of PSE. The aim of the present review was to discuss current perspectives on diagnosis and treatment of PSS and PSE, both in adult and paediatric patients.

Frequency and Stratification of Epileptogenic Lesions in Elderly With New Onset Seizures

Objective: To evaluate prospectively the frequency of epileptogenic lesions in a consecutive cohort of elderly patients presenting with new onset unprovoked seizures, and who underwent a complete evaluation including dedicated epilepsy protocol MRI.

Methods and materials: We included all consecutive patients 60 years or older who participated in a prospective study on new onset epilepsy. The work-up included the acquisition of a dedicated epilepsy protocol MRI and a 3 h video/EEG recording. We evaluated the frequency and types of epileptogenic lesions in the whole cohort and stratified those variables by age, gender, types and number of seizures at presentation. We also correlated the EEG findings with the clinical characteristics and neuroimaging results.

Results: Of the 101 patients enrolled in the study and who underwent an epilepsy protocol MRI, an epileptogenic lesion was identified in 67% of cases. The most common etiologies were vascular events, followed by tumoral causes and traumatic brain injuries. Epileptogenic lesions were more likely to be identified in patients who presented with only focal aware and impaired awareness seizures. In addition, patients with tumoral epilepsy were significantly more likely to only experience those seizure types compared to patients with other pathological substrates. Interictal/ictal discharges were detected in the EEG of 21% of patients. Epileptiform discharges were significantly more frequent in patients with an epileptogenic lesion on brain MRI, especially in those with a brain tumor.

Conclusions: Our results stress the importance of obtaining a dedicated epilepsy protocol MRI in elderly patients with new onset seizures. An epileptogenic lesion will be identified in approximately two thirds of patients with important implications regarding initiation of treatment. In addition, the data underscore the value of distinguishing the types of seizures experienced at presentation as this will apprise the treating physician on the likelihood of identifying an epileptogenic lesion and on the probable etiologies.

Seizures after transplantation

PURPOSE

To summarize information on the history, incidence, clinical manifestation, best treatment, as well as prognosis of seizures in transplant recipients.

METHODS

In October 2017, we searched the literature on PubMed in English with the search terms: "transplantation" AND "seizure", "transplantation" AND "epilepsy", "transplantation"AND "status epilepticus", "immunosuppressant" AND "seizure", "immunosuppressant" AND "epilepsy". Publications not based on new data and original research were not included in this article.

RESULTS

Seizures including generalized seizures, focal seizures and status epilepticus are a common central nervous system complication after transplantation. The incidence of seizures varied between different kinds of transplantations. The reported incidence of seizures was 7%-27% in association with solid organ transplantations and 1.6%-15.4% with hematopoietic stem cell transplantation. Most of seizures appeared in the early post-transplantation period. Patients often had a favorable prognosis, however, in some conditions, recurrent or intractable seizures may occur.

CONCLUSIONS

The underlying pathogenesis of new-onset seizures or epilepsy in recipients of transplantation needs to be further elucidated. In addition, more information is required from prospective studies and research focusing on therapeutic strategies.

Reliable and Elastic Propagation of Cortical Seizures In Vivo

Mapping the fine-scale neural activity that underlies epilepsy is key to identifying potential control targets of this frequently intractable disease. Yet, the detailed in vivo dynamics of seizure progression in cortical microcircuits remain poorly understood. We combine fast (30-Hz) two-photon calcium imaging with local field potential (LFP) recordings to map, cell by cell, the spread of locally induced (4-AP or picrotoxin) seizures in anesthetized and awake mice. Using single-layer and microprism-assisted multilayer imaging in different cortical areas, we uncover reliable recruitment of local neural populations within and across cortical layers, and we find layer-specific temporal delays, suggesting an initial supra-granular invasion followed by deep-layer recruitment during lateral seizure spread. Intriguingly, despite consistent progression pathways, successive seizures show pronounced temporal variability that critically depends on GABAergic inhibition. We propose an epilepsy circuit model resembling an elastic meshwork, wherein ictal progression faithfully follows preexistent pathways but varies flexibly in time, depending on the local inhibitory restraint.

Nonconvulsive status epilepticus in rats leads to brain pathology

OBJECTIVE

Status epilepticus (SE) is an abnormally prolonged epileptic seizure that if associated with convulsive motor symptoms is potentially life threatening for a patient. However, 20%-40% of patients with SE lack convulsive events and instead present with more subtle semiology such as altered consciousness and less motor activity. Today, there is no general consensus regarding to what extent nonconvulsive SE (NCSE) is harmful to the brain, which adds uncertainty to stringent treatment regimes.

METHODS

Here, we evaluated brain pathology in an experimental rat and mouse model of complex partial NCSE originating in the temporal lobes with Western blot analysis, immunohistochemistry, and ex vivo diffusion tensor imaging (DTI). The NCSE was induced by electrical stimulation with intrahippocampal electrodes and terminated with pentobarbital anesthesia. Video-electroencephalographic recordings were performed throughout the experiment.

RESULTS

DTI of mice 7 weeks post-NCSE showed no robust long-lasting changes in fractional anisotropy within the hippocampal epileptic focus. Instead, we found pathophysiological changes developing over time when measuring protein levels and cell counts in extracted brain tissue. At 6 and 24 hours post-NCSE in rats, few changes were observed within the hippocampus and cortical or subcortical structures in Western blot analyses of key components of the cellular immune response and synaptic protein expression, while neurodegeneration had started. However, 1 week post-NCSE, both excitatory and inhibitory synaptic protein levels were decreased in hippocampus, concomitant with an excessive microglial and astrocytic activation. At 4 weeks, a continuous immune response in the hippocampus was accompanied with neuronal loss. Levels of the excitatory synaptic adhesion molecule N-cadherin were decreased specifically in rats that developed unprovoked spontaneous seizures (epileptogenesis) within 1 month following NCSE, compared to rats only exhibiting acute symptomatic seizures within 1 week post-NCSE.

SIGNIFICANCE

These findings provide evidence for a significant brain pathology following NCSE in an experimental rodent model.

Hypoparathyroidism Causing Seizures: When Epilepsy Does Not Fit

A 24-year-old man presented to the Chris Hani Baragwanath Academic Hospital emergency department with recurrent seizures having previously been diagnosed with epilepsy from age 14. The biochemical investigations and brain imaging were suggestive of seizures secondary to hypocalcemia, and a diagnosis of idiopathic hypoparathyroidism was confirmed. After calcium and vitamin D replacement, the patient recovered well and is seizure free, and off antiepileptic therapy. This case highlights the occurrence of brain calcinosis in idiopathic hypoparathyroidism; the occurrence of acute symptomatic seizures due to provoking factors other than epilepsy; and the importance, in the correct clinical setting, of considering alternative, and sometimes treatable, causes of seizures other than epilepsy.

Imaging for Adults With Seizures and Epilepsy

PURPOSE OF REVIEW

This article discusses structural and functional neuroimaging findings in patients with seizures and epilepsy. The indications for neuroimaging in these patients and the potential diagnostic utility of these studies are presented.

RECENT FINDINGS

Patients presenting with new seizures typically require urgent imaging to rule out a critical underlying cause. MRI is the structural neuroimaging procedure of choice in individuals with epilepsy. Specific epilepsy protocols should be considered to increase the diagnostic yield of neuroimaging in patients with structural lesions associated with focal or generalized seizures. Common epileptogenic pathologic processes include mesial temporal sclerosis, malformations of cortical development, focal encephalomacia, primary brain tumors, vascular malformations, and neurocysticercosis. Functional neuroimaging studies are usually restricted to the evaluation of patients with drug-resistant focal epilepsy who are being considered for surgical treatment.

SUMMARY

The role of neuroimaging in epilepsy depends on the appropriate clinical indication. In patients without known epilepsy presenting with acute seizures, structural imaging is essential to rule out an underlying etiology (eg, subdural hematoma) that may require a specific therapeutic intervention. In individuals with new or previously uninvestigated epilepsy, MRI serves multiple purposes, including identifying a causative focal lesion and helping to diagnose the epilepsy type. In a significant number of patients with epilepsy, the MRI results are normal or reveal indeterminate findings. For patients with drug-resistant focal epilepsy, functional neuroimaging techniques, such as fludeoxyglucose-positron emission tomography (FDG-PET), ictal single-photon emission computed tomography (SPECT), or functional MRI (fMRI), may assist in surgical planning, especially in patients with MRI-negative epilepsy, whose prognosis for a seizure-free outcome after surgery is worse than for patients with an epileptogenic lesion on structural MRI.

Prevalence, causes, and behavioral and emotional comorbidities of acute symptomatic seizures in Africa: A critical review

Seizures with fever includes both febrile seizures (due to nonneurological febrile infections) and acute symptomatic seizures (due to neurological febrile infections). The cumulative incidence (lifetime prevalence) of febrile seizures in children aged ≤6 years is 2-5% in American and European studies, but there are no community-based data on acute symptomatic seizures in Africa. The incidence of acute symptomatic seizures in sub-Saharan Africa is more than twice that in high-income countries. However, most studies of acute symptomatic seizures from Africa are based on hospital samples or do not conduct surveys in demographic surveillance systems, which underestimates the burden. It is difficult to differentiate between febrile seizures and acute symptomatic seizures in Africa, especially in malaria-endemic areas where malaria parasites can sequester in the brain microvasculature; but this challenge can be addressed by robust identification of underlying causes. The proportion of complex acute symptomatic seizures (i.e., seizures that are focal, repetitive, or prolonged) in Africa are twice that reported in other parts of the world (>60% vs. ∼30%), which is often attributed to falciparum malaria. These complex phenotypes of acute symptomatic seizures can be associated with behavioral and emotional problems in high-income countries, and outcomes may be even worse in Africa. One Kenyan study reported behavioral and emotional problems in approximately 10% of children admitted with acute symptomatic seizures, but it is not clear whether the behavioral and emotional problems were due to the seizures, shared genetic susceptibility, etiology, or underlying neurological damage. The underlying neurological damage in acute symptomatic seizures can lead not only to behavioral and emotional problems but also to neurocognitive impairment and epilepsy. Electroencephalography may have a prognostic role in African children with acute symptomatic seizures. There are significant knowledge gaps regarding acute symptomatic seizures in Africa, which results in lack of reliable estimates for planning interventions. Future epidemiological studies of acute symptomatic seizures should be set up in Africa.

Evaluation of the first seizure patient: Key points in the history and physical examination

PURPOSE

This review will present the history and physical examination as the launching point of the first seizure evaluation, from the initial characterization of the event, to the exclusion of alternative diagnoses, and then to the determination of specific acute or remote causes. Clinical features that may distinguish seizures from alternative diagnoses are discussed in detail, followed by a discussion of acute and remote first seizure etiologies.

METHODS

This review article is based on a discretionary selection of English language articles retrieved by a literature search in the PubMed database, and the authors' clinical experience.

RESULTS

The first seizure is a dramatic event with often profound implications for patients and family members. The initial clinical evaluation focuses on an accurate description of the spell to confirm the diagnosis, along with careful scrutiny for previously unrecognized seizures that would change the diagnosis more definitively to one of epilepsy. The first seizure evaluation rests primarily on the clinical history, and to a lesser extent, the physical examination.

CONCLUSIONS

Even in the era of digital EEG recording and neuroimaging, the initial clinical evaluation remains essential for the diagnosis, treatment, and prognostication of the first seizure.

Clinical predictors of seizure recurrence after the first post-ischemic stroke seizure

Background

The number of patients suffering post-stroke seizure after ischemic stroke (PSSi) is quite considerable, especially because ischemic stroke is more prevalent than hemorrhage in the general population. This study aimed to determine the predicting factors for seizure recurrence in ischemic stroke survivors and develop a clinical scoring system for the prediction of risks for seizure recurrence after the first PSSi.

Methods

We reviewed 3792 ischemic stroke patients from the Ewha Stroke Registry. A total of 124 (3.3 %) patients who experienced PSSi were recruited (mean follow-up for 44.4 months). Medical records concerning the etiology, functional disability, seizure onset latency from stroke, type of seizure, electroencephalography (EEG), and neuroimaging findings were statistically analyzed to derive a seizure recurrence risk scoring system.

Results

Seizures recurred in 35.4 % (17/48) of early PSSi patients (≤1 week since stroke onset) and 48.7 % (37/76) of late PSSi (>1 week) patients. Atrial fibrillation, large sized, and cortical stroke lesion were more common in late onset PSSi compared to those in early onset PSSi (p < 0.05). Seizure recurrence tended to be more prevalent in early PSSi patients with male gender, atrial fibrillation or cortical stroke lesion, severe functional disability, and partial seizures. Seizure recurrence in late PSSi group was more common in patients of young age (≤65 years old), male gender, large lesion size, and partial seizure type. The validity of seizure recurrence risk score in the early PSSi group was better when evaluating based on gender, atrial fibrillation, cortical lesion, functional disability, and partial seizure type, with sensitivity of 70.6 % and specificity of 71.0 %.

Conclusions

Our study characterized the high risk group for seizure recurrence in patients with the first PSSi. PSSi patients with high risk score of seizure recurrence had a greater chance of developing epilepsy later. Therefore, they should be considered for further treatment such as antiepileptic drug medication in clinical practice.

Epidemiology of Pediatric Convulsive Status Epilepticus With Fever in the Emergency Department: A Cohort Study of 381 Consecutive Cases

Pediatric convulsive status epilepticus with fever is common in the emergency setting but leads to severe neurological sequelae in some patients. To explore the epidemiology of convulsive status epilepticus with fever, a retrospective cohort covering all convulsive status epilepticus cases with fever seen in the emergency department of a tertiary care children's hospital were consecutively collected. Of the 381 consecutive cases gathered, 81.6% were due to prolonged febrile seizure, 6.6% to encephalopathy/encephalitis, 0.8% to meningitis, and 7.6% to epilepsy. In addition, seizures were significantly longer in encephalopathy/encephalitis cases than in prolonged febrile seizure cases (log rank test, P < .001). These results provide for the first time the pretest probability of final diagnoses in children with convulsive status epilepticus with fever in the emergency setting, and will help optimize the management of pediatric patients presenting to the emergency department with convulsive status epilepticus with fever.

Poststroke epilepsy: update and future directions

Stroke is among the most common causes of epilepsy after middle age. Patients with poststroke epilepsy (PSE) differ in several respects from patients with other forms of structural-metabolic epilepsy; not least in age, age-related sensitivity to side effects of antiepileptic drugs (AEDs), and specific drug-drug interaction issues related to secondary-stroke prophylaxis. Encouragingly, there has lately been remarkable activity in the study of PSE. Three developments in PSE research deserve particular focus. First, large prospective trials have established the incidence and risk factors of PSE in the setting of modern stroke care. Stroke severity, cortical location, young age, and haemorrhage remain the most important risk factors. Second, although more studies are needed, epidemiological data indicate that the risk of PSE may be influenced, for instance, by statin treatment. Third, studies are emerging regarding the treatment and prognosis of PSE. Levetiracetam and lamotrigine may be well tolerated treatment options and seizure freedom is achieved in at least a similar proportion of patients as in other epilepsies. Furthermore, new animal models such as photothrombotic stroke gives hope of a more clear understanding of PSE epileptogenesis in the near future. In summary, PSE shows indications of maturing into an independent epilepsy research field. This review summarizes recent advances in our understanding of PSE and provides an update on management issues such as diagnosis, AED selection, and prognosis. Finally, future research challenges in the field are outlined.

Investigation of Deaths in Seizure Patients

Epilepsy is commonly encountered in forensic pathology and is ultimately determined to be the cause of death in 1–2% of medicolegal death investigations. Epilepsy is a risk factor for death from external causes, including accidents and drowning. More commonly, deaths result from the underlying epilepsy pathology, including intracranial neoplasms, cerebrovascular disease, status epilepticus, and sudden unexpected death in epilepsy (SUDEP). SUDEP refers to the sudden death in an epilepsy patient that lacks an alternative anatomic or toxicological cause of death. At autopsy, intracranial pathology is present in the majority of epilepsy-related deaths and is more likely to be identified following brain fixation. Common findings include brain tumors, mesial temporal sclerosis, and malformations of cortical development. Death investigators should pay particular attention to clinical history to establish a clear history of epilepsy and to determine seizure type, frequency, underlying etiology, and prior medical and surgical treatments as well as other comorbid medical conditions. A complete autopsy with toxicology is necessary to identify other causes of death, particularly in cases of suspected SUDEP. While toxicology may be helpful in some cases, caution must be taken in interpreting postmortem antiepileptic drug concentrations as levels decrease postmortem.

Recurrent seizures following focal motor status epilepticus in a patient with non-ketotic hyperglycemia and acute cerebral infarction

Focal motor status epilepticus (FMSE) is often associated non-ketotic hyperglycemia (NKH). There are no previous reports describing FMSE with NKH that was accompanied by an acute cerebral infarction and its long term follow-up result. We describe the case of a patient having focal motor status epilepticus (FMSE) associated with non-ketotic hyperglycemia (NKH) and acute cerebral infarction who later developed recurrent unprovoked seizures. A small acute infarct was observed in the left frontal subcortical area on diffusion-weighted images (DWI). FMSE was initially controlled with short term antiepileptic drugs and strict glucose control. Two years later, recurrent seizures occurred, and long-term antiepileptic drug treatment was administered. DWI should be considered for acute cerebral infarction in patients having FMSE associated with NKH, and careful follow-up should be conducted for such patients.

Seizures after single-agent overdose with pharmaceutical drugs: analysis of cases reported to a poison center

CONTEXT

Seizures during intoxications with pharmaceuticals are a well-known complication. However, only a few studies report on drugs commonly involved and calculate the seizure potential of these drugs.

OBJECTIVES

To identify the pharmaceutical drugs most commonly associated with seizures after single-agent overdose, the seizure potential of these pharmaceuticals, the age-distribution of the cases with seizures and the ingested doses.

METHODS

A retrospective review of acute single-agent exposures to pharmaceuticals reported to the Swiss Toxicological Information Centre (STIC) between January 1997 and December 2010 was conducted. Exposures which resulted in at least one seizure were identified. The seizure potential of a pharmaceutical was calculated by dividing the number of cases with seizures by the number of all cases recorded with that pharmaceutical. Data were analyzed using descriptive statistics.

RESULTS

We identified 15,441 single-agent exposures. Seizures occurred in 313 cases. The most prevalent pharmaceuticals were mefenamic acid (51 of the 313 cases), citalopram (34), trimipramine (27), venlafaxine (23), tramadol (15), diphenhydramine (14), amitriptyline (12), carbamazepine (11), maprotiline (10), and quetiapine (10). Antidepressants were involved in 136 cases. Drugs with a high seizure potential were bupropion (31.6%, seizures in 6 of 19 cases, 95% CI: 15.4-50.0%), maprotiline (17.5%, 10/57, 95% CI: 9.8-29.4%), venlafaxine (13.7%, 23/168, 95% CI: 9.3-19.7%), citalopram (13.1%, 34/259, 95% CI: 9.5-17.8%), and mefenamic acid (10.9%, 51/470, 95% CI: 8.4-14.0%). In adolescents (15-19y/o) 23.9% (95% CI: 17.6-31.7%) of the cases involving mefenamic acid resulted in seizures, but only 5.7% (95% CI: 3.3-9.7%) in adults (≥ 20y/o; p < 0.001). For citalopram these numbers were 22.0% (95% CI: 12.8-35.2%) and 10.9% (95% CI: 7.1-16.4%), respectively (p = 0.058). The probability of seizures with mefenamic acid, citalopram, trimipramine, and venlafaxine increased as the ingested dose increased.

CONCLUSIONS

Antidepressants were frequently associated with seizures in overdose, but other pharmaceuticals, as mefenamic acid, were also associated with seizures in a considerable number of cases. Bupropion was the pharmaceutical with the highest seizure potential even if overdose with bupropion was uncommon in our sample. Adolescents might be more susceptible to seizures after mefenamic acid overdose than adults. "Part of this work is already published as a conference abstract for the XXXIV International Congress of the European Association of Poisons Centres and Clinical Toxicologists (EAPCCT) 27-30 May 2014, Brussels, Belgium." Abstract 8, Clin Toxicol 2014;52(4):298.

Autoantibodies to neuronal antigens in children with new-onset seizures classified according to the revised ILAE organization of seizures and epilepsies

PURPOSE

Potentially pathogenic autoantibodies are found increasingly in adults with seizure disorders, including focal seizures and those of unknown cause. In this study, we investigated a cohort of children with new-onset seizures to see whether there were autoantibodies and the relationship to any specific seizure or epilepsy type.

METHODS

We prospectively recruited 114 children (2 months to 16 years) with new-onset seizures presenting between September 2009 and November 2011, as well as 65 controls. Patients were clinically assessed and classified according to the new International League Against Epilepsy (ILAE) organization of seizures and epilepsies classification system. Sera were tested for autoantibodies to a range of antigens, blind to the clinical and classification details.

KEY FINDINGS

Eleven (9.7%) of 114 patients were positive for one or more autoantibodies compared to 3 of 65 controls (4.6%, p = ns). Patients had antibodies to the voltage-gated potassium channel (VGKC) complex (n = 4), contactin-associated protein-like 2 (CASPR2) (n = 3), N-methyl-d-aspartate receptors (NMDARs) (n = 2), or VGKC-complex and NMDAR (n = 2). None had antibodies to glutamic acid decarboxylase, contactin-2, or to glycine, 2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl) propionic acid (AMPA), or γ-aminobutyric acid B receptors. Ten of these 11 patients were classified as having epilepsy according to the new ILAE organization of seizures and epilepsy. Although, there were no significant differences in the demographic and clinical features between antibody-positive and antibody-negative patients, the classification of "unknown cause" was higher in the antibody positive (7/10; 70%) compared with the antibody negative subjects (23/86; 26.7%; p = 0.0095, Fisher's exact test). Furthermore, four of these seven patients with epilepsy (57.1%) were classified as having predominantly focal seizures compared with 12 of the 86 antibody-negative patients (13.9%; p = 0.015).

SIGNIFICANCE

Because autoantibodies were more frequent in pediatric patients with new-onset epilepsy of "unknown cause," often with focal epilepsy features, this group of children may benefit most from autoantibody screening and consideration of immune therapy.