First seizure in adults: a prospective study from the emergency department

Gamma Entrainment in a Large Retrospective Cohort: Implications for Photic Stimulation Therapy for Alzheimer's Disease

BACKGROUND

Studies on mice models of Alzheimer's disease (AD) have suggested potential therapeutic benefits of intermittent photic stimulation at 40 Hz.

OBJECTIVE

We examined the physiological response of 40 Hz intermittent photic stimulation (IPS) on routine EEG in a large retrospective cohort to investigate the effects of age on induced gamma oscillations by intermittent photic stimulation. Since most AD patients are elderly, it is important for future research to know if age affects photic stimulation.

METHODS

Retrospective data from 1,464 subjects aged 0- 91. We performed frequency analysis and automatic peak detection and used regression analysis to investigate the effects of age and sex on peak frequencies and amplitude changes. To investigate the spread of the induced gamma oscillations, we assessed averaged topographies of 40 Hz band power.

RESULTS

There was a statistically significant but very minor effect of age on amplitude change (- 0.002 normalized power per year, p < 0.0001) but not for sex (p = 0.728). Detection probability of induced peaks was significantly predicted by both age (OR = 0.988, CI 95 % [0.984, 0.993], p < 0.00001) and sex (OR = 0.625, CI 95 % [0.496, 0.787>], p < 0.0001). The induced 40 Hz gamma entrainment is spatially confined to the occipital area.

CONCLUSION

There is a significant effect of age on induced gamma activity, but advanced age does not fundamentally change the behavior of the response in either magnitude or spatial distribution. This fact is important regarding future research into the possible therapeutic effects of photic stimulation in patients with AD.

Yield of Emergent CT in Patients With Epilepsy Presenting With a Seizure

Background

Studies of emergent neuroimaging in the management of patients presenting with a breakthrough seizure are lacking. We sought to determine how often emergent computed tomography (CT) scans are obtained in patients with known epilepsy presenting with a seizure and how often acute abnormalities are found.

Methods

This multicenter retrospective cohort study was performed in the emergency department at 2 academic medical centers. The primary outcomes were percentage of visits where a CT scan was obtained, whether CT findings represented acute abnormalities, and whether these findings changed acute management.

Results

Of the 396 visits included, CT scans were obtained in 39%, and 8% of these scans demonstrated acute abnormalities. Patients who were older, had status epilepticus, a brain tumor, head trauma, or an abnormal examination were all significantly more likely to undergo acute neuroimaging (P < .05). In the multivariable model, only history of brain tumor (odds ratio [OR] 5.88, 95% confidence interval [CI], 1.33-26.1) and head trauma as a result of seizure (OR 3.92, 95% CI, 1.01-15.2) reached statistical significance in predicting an acutely abnormal scan. The likelihood of an acute imaging abnormality in visits for patients without a history of brain tumor or head trauma as a result of the seizure was 2.7% (2 visits). Both of these patients had abnormal neurological examinations.

Conclusion

Obtaining an emergent CT scan for patients with epilepsy presenting with a seizure may be avoidable in most cases, but might be indicated for patients with a history of brain tumor or head trauma as a result of seizure.

Laboratory markers of cardiac and metabolic complications after generalized tonic-clonic seizures

Background

Generalized tonic-clonic seizures (GTCS) frequently lead to emergency inpatient referrals. Laboratory blood values are routinely performed on admission to detect underlying causes and metabolic or cardiac complications. Our goal was to assess the nature and frequency of complications occurring in association with GTCS.

Methods

We retrospectively extracted data from emergency protocols and discharge letters of adult patients admitted to the Department of Epileptology between 01/2010 and 06/2015. Inclusion criteria were diagnosis of GTCS and admission via emergency services. Exclusion criteria were status epilepticus prior to admission to hospital and non-generalized seizures.

Results

A total of 223 patients (of 986 screened cases) were included. Overall, 1.8% required intubation while 1.3% had less severe respiratory problems. In 5.6% of patients, a transient hypoxemia was measured. Hypertensive urgencies affected 7.8% of the patients, sinus tachycardia occurred in 41.2%. Troponin I (cTNI) was determined in 75 patients and was increased in 12% of these cases. Occurrence of elevated cTNI levels was significantly correlated with patient’s age. Four patients were diagnosed with NSTEMI and one patient with STEMI. Creatine kinase (CK) was increased in 59.4% of the patients, with <5-fold increases in 47%, <10-fold in 5.8% and >10-fold increases in 4.3%. Rhabdomyolysis with an >50 fold increase in CK was detected in 1.9% of patients. Prolonged disturbances of consciousness affected 5% of cases while agitation, delirium, and psychotic episodes occurred in 6.3%. Minor traumatic injuries affected 45.7% of patients.

Conclusions

Troponin elevations in association with GTCS are one of the more common complications after emergency admissions especially in older patients. In our selected patient population, serious complications such as intracranial hemorrhage, myocardial infarction and acute renal failure occurred in <1% of GTCS only.

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.

Computed tomography abnormalities and epidemiology of adult patients presenting with first seizure to the emergency department in Qatar

OBJECTIVES

There is little information available from the Middle Eastern region on adult patients presenting with first seizure. The objectives of this study were to describe epidemiological characteristics of patients presenting to the emergency department (ED) in Doha, Qatar, with first seizure and to determine the incidence of computed tomographic (CT) scan abnormalities.

METHODS

A retrospective cohort study was conducted on all adult patients with first seizure presenting to Hamad General Hospital ED over a 1-year period (June 2012 through May 2013). Electronic patient records were reviewed for demographics, neuroimaging, electroencephalography, laboratory test results, and medications administered.

RESULTS

There were 439 patients who satisfied inclusion criteria. Patients were aged a mean of 35.3 years (95% confidence interval [CI] = 33.92 to 36.69 years) with a male-to-female ratio of five to one. CT abnormalities were detected in 154 patients (35.3%; 95% CI = 30.81% to 39.82%). Out of reported abnormal scans, 14.7% patients had significant abnormalities such as neurocysticercosis (9.2%); brain metastasis and neoplasm (3.4%); and subarachnoid and subdural hemorrhage, cavernous sinus thrombosis, acute stroke, and brain edema (2.0%). None of the patients had any electrolyte abnormalities, and three patients had hypoglycemia. Patients with initial abnormal CT brain results were more likely to have recurrent seizures (OR = 1.65; 95% CI = 1.11 to 2.45) within 6 months.

CONCLUSIONS

Adults who presented with first seizure to the ED in Qatar had a young male predominance, and a high proportion of brain CT scans were reported as abnormal. It is recommended that all such patients in this population should undergo prompt CT scanning in the ED, but the utility of routine electrolyte tests requires further investigation.

Emergency department seizure epidemiology

Although only 3% of people in the United States are diagnosed with epilepsy, 11% will have at least one seizure during their lifetime. Seizures account for about 1% of all emergency department (ED) visits, and about 2% of visits to children's hospital EDs. Seizure accounts for about 3% of prehospital transports. In adult ED patients, common causes of seizure are alcoholism, stroke, tumor, trauma, and central nervous system infection. In children, febrile seizures are most common. In infants younger than 6 months, hyponatremia and infection are important considerations. Epilepsy is an uncommon cause of seizures in the ED, accounting for a minority of seizure-related visits. Of ED patients with seizure, about 7% have status epilepticus, which has an age-dependent mortality averaging 22%.

The emergency department evaluation of the adult patient who presents with a first-time seizure

Up to 5% of the population will experience at least 1 nonfebrile seizure at some point during their lifetime. The management of a patient who has had a first-time seizure is driven by the history and physical examination. In almost one-half of these patients, the cause of their seizure is not identified. In general, patients with comorbidities, a focal neurologic examination, or who have not returned to a normal baseline mental status require an extensive diagnostic evaluation including a noncontrast head computed tomography (CT) scan in the emergency department (ED). Adults with a first-time seizure, with no comorbidities, and who have returned to a normal baseline require only serum glucose and electrolyte determination. Women of reproductive age also require a pregnancy test. Patients with a normal neurologic examination, normal laboratory results, and no signs of structural brain disease do not require hospitalization or antiepileptic medications. Initiation of antiepileptic therapy depends on the assessed risk for recurrence, in conjunction with a neurologist consultation.

Seizures in patients with low-grade gliomas--incidence, pathogenesis, surgical management, and pharmacotherapy

Seizures complicate the clinical course of > 80% of patients with low-grade gliomas. Patients with some tumor variants almost always have epilepsy. Diffuse low-grade gliomas (LGG) are believed to cause epilepsy through partial deafferentiation of nearby brain cortex (denervation hypersensitivity). Glioneural tumors may interfere with local neurotransmitter levels and are sometimes associated with structural abnormalities of the brain which may produce seizures. The severity of tumor associated epilepsy varies considerably between patients. Some cases may present with a first seizure. Others suffer from long-standing pharmacoresistant epilepsy. Seizure control rates of > 70-80% can be expected after complete tumor resections. Patients with drug-resistant epilepsy require a comprehensive preoperative epileptological work-up which may include the placement of subdural (and intraparenchymal) electrodes or intraoperative electrocorticography (ECoG) for the delineation of extratumoral seizure foci. Partial and subtotal tumor resections are helpful in selected cases, i.e. for gliomas involving the insula. In one series, 40% of patients presented for surgery with uncontrolled seizures, i.e. medical therapy alone often fails to control tumor-related epilepsy. Use of the newer (second generation) non-enzyme inducing antiepileptic drugs (non-EIAED) is encouraged since they seem to have lesser interactions with other medications (e.g. chemotherapy). Chemotherapy and irradiation may have some minor beneficial effects on the patients' seizure disorder. Overall 60-70% of patients may experience recurrent epilepsy during long-term follow-up. Recurrent seizures (not infrequently heralding tumor recurrence) after surgery continue to pose significant clinical problems.

Seizure visits in US emergency departments: epidemiology and potential disparities in care

INTRODUCTION

While epilepsy is a well-characterized disease, the majority of emergency department (ED) visits for "seizure" involve patients without known epilepsy. The epidemiology of seizure presentations and national patterns of management are unclear. The aim of this investigation was to characterize ED visits for seizure in a large representative US sample and investigate any potential impact of race or ethnicity on management.

METHODS

Seizure visits from the National Hospital Ambulatory Medical Care Survey (NHAMCS) from 1993 to 2003 were analysed. Demographic factors associated with presentation, neuroimaging and hospital admission in the USA were analysed using controlled multivariate logistic regression.

RESULTS

Seizure accounts for 1 million ED visits annually [95% confidence interval (CI): 926,000-1,040,000], or 1% of all ED visits in the USA. Visits were most common among infants, at 8.0 per 1,000 population (95% CI: 6.0-10.0), and children aged 1-5 years (7.4; 95% CI: 6.4-8.4). Seizure was more likely among those with alcohol-related visits [odds ratio (OR): 3.2; 95% CI: 2.7-3.9], males (OR: 1.4; 95% CI: 1.3-1.5) and Blacks (OR: 1.4; 95% CI: 1.3-1.6). Neuroimaging was used less in Blacks than Whites (OR: 0.6; 95% CI: 0.4-0.8) and less in Hispanics than non-Hispanics (OR: 0.6; 95% CI: 0.4-0.9). Neuroimaging was used less among patients with Medicare (OR: 0.4; 95% CI: 0.2-0.6) or Medicaid (OR: 0.5; 95% CI: 0.4-0.7) vs private insurance and less in proprietary hospitals. Hospital admission was less likely for Blacks vs Whites (OR: 0.6; 95% CI: 0.4-0.8).

CONCLUSION

Seizures account for 1% of ED visits (1 million annually). Seizure accounts for higher proportions of ED visits among infants and toddlers, males and Blacks. Racial/ethnic disparities in neuroimaging and hospital admission merit further investigation.

Increased adverse drug reactions to antimicrobials and anticonvulsants in patients with HIV infection

OBJECTIVE

To review the incidence, signs, symptoms, and mechanisms of adverse drug reactions (ADRs) to sulfonamides, anticonvulsants, and antimycobacterial medications among people with HIV.

DATA SOURCES

Searches of MEDLINE/PubMed (1980-November 2005) and National Library of Medicine Meeting Abstracts (1989-November 2005), as well as hand searches of journals and abstracts, were conducted to identify primary literature. Reference lists were reviewed to identify additional relevant reports.

STUDY SELECTION AND DATA EXTRACTION

Relevant articles and abstracts, particularly of in vitro experiments and clinical studies, were compiled and reviewed.

DATA SYNTHESIS

ADRs, especially in HIV-infected patients, are a cause for concern. Sulfonamides, anticonvulsants, and antimycobacterial drugs are commonly used to prevent and treat complications of HIV, including seizures and opportunistic infections. Patients with HIV have a much greater rate of ADRs to these drug classes, including severe and life-threatening hypersensitivity reactions. Several mechanisms of these ADRs have been postulated. Sulfamethoxazole and anticonvulsant hypersensitivity may involve the increased formation and decreased detoxification of reactive metabolites. The mechanisms for the marked increase in hypersensitivity ADRs to antimycobacterial drugs may be related to an altered immune profile in patients infected with both tuberculosis and HIV.

CONCLUSIONS

ADRs to antimicrobial and anticonvulsant therapy cause markedly increased morbidity and mortality in HIV-positive patients. Further research involving the interaction between HIV and the increased ADRs to these drugs is required.

Early management of adults with an uncomplicated first generalised seizure

A literature review of first seizures in adults was performed and a management algorithm was constructed. This review highlights the importance of a thorough history and examination, routine biochemistry and haematology, an electrocardiogram, selected neuroimaging, discharge planning with driving and lifestyle advice, and follow-up in a specialist clinic.

Special populations: The management of seizures in HIV-positive patients

An increasing percentage of patients with new-onset seizures are HIV positive. The evaluation and management is distinctly different from managing the non-HIV-infected patient. Clinicians must be familiar with comorbid infectious etiologies and the relative value of electroencephalogram, imaging, and serum and cerebrospinal fluid laboratory tests. Traditional antiepileptic drug (AED) therapies are contraindicated and may lead to increased HIV viral replication through either directed cellular mechanisms or interference with antiretroviral therapies. Newer AEDs have pharmacokinetic properties that make them reasonable choices, although none have been specifically studied for efficacy or safety in HIV. Lastly, optimal choice of an AED should reflect commonly encountered neurologic and psychiatric comorbidities.

The role of routine serum laboratory tests in children presenting to the emergency department with unprovoked seizures

The role of laboratory tests in the treatment of patients with unprovoked seizures in the emergency department (ED) is unclear. To better determine the diagnostic value of routine serum chemistries (glucose, electrolytes) in these patients, and to identify risk factors predicting abnormality, 107 children who presented to the ED with unprovoked seizures were evaluated prospectively. Serum electrolytes and glucose were determined in 54 patients. The incidence of abnormal serum biochemical values was 14.8%; it was higher in patients with a first seizure, younger age, gastrointestinal symptoms, or change in mental status. These data indicate that serum glucose and/or electrolyte abnormalities are rare in patients evaluated in the ED for unprovoked seizures. Based on these findings and those reported in previous studies, performance of these tests is recommended in children younger than 2 years old, presenting with a first seizure, or when accompanied by gastrointestinal or diffuse neurologic symptoms.

Neurocysticercosis in radiographically imaged seizure patients in U.S. emergency departments

Neurocysticercosis appears to be on the rise in the United States, based on immigration patterns and published cases series, including reports of domestic acquisition. We used a collaborative network of U.S. emergency departments to characterize the epidemiology of neurocysticercosis in seizure patients. Data were collected prospectively at 11 university-affiliated, geographically diverse, urban U.S. emergency departments from July 1996 to September 1998. Patients with a seizure who underwent neuroimaging were included. Of the 1,801 patients enrolled in the study, 38 (2.1%) had seizures attributable to neurocysticercosis. The disease was detected in 9 of the 11 sites and was associated with Hispanic ethnicity, immigrant status, and exposure to areas where neurocysticercosis is endemic. This disease appears to be widely distributed and highly prevalent in certain populations (e.g., Hispanic patients) and areas (e.g., Southwest).

The role of brain computed tomography in evaluating children with new onset of seizures in the emergency department

BACKGROUND

The purpose of neuroimaging of a patient with new onset of seizures is to demonstrate cause and explore the prognosis. It was recently recommended that emergency brain computed tomography (CT) be performed only in adult seizure patients with an increased likelihood of life-threatening lesions, i.e., those with new focal deficits, persistent altered mental status, fever, recent trauma, persistent headaches, history of cancer, history of anticoagulation, or suspicion of acquired immunodeficiency syndrome. The objective of this study was to determine the diagnostic utility of emergency brain CT in children who present to the emergency department with new onset of seizures.

METHODS

A 1-year retrospective chart review of all children who presented to the emergency department of the Schneider Children's Hospital with a new onset of seizures and who underwent CT of the brain, excluding children with simple febrile seizures.

RESULTS

Sixty-six patients, 34 boys and 32 girls with a mean age of 4.9 years, qualified for inclusion in the study. Fifty-two patients (78.8%) had normal CT results and 14 patients (21.2%) had abnormal CT results. Seizure cause was considered cryptogenic in 33 patients, of whom 2 (6%) had abnormal CT results; neither patient required intervention. Seizure cause was considered symptomatic in 20 patients, of whom 12 (60%) had abnormal CT results (p < 0.0001). In two patients with abnormal CT scans (both acute symptomatic), the imaging findings were of immediate therapeutic significance and were predictable from the clinical history and the physical examination. None of the 13 patients with complex febrile seizure cause had an abnormal CT scan. Patients with partial convulsive seizures were more likely to have abnormal CT scans than patients with generalized convulsive seizures, but the difference was not statistically significant.

CONCLUSIONS

The routine practice in many pediatric emergency departments of obtaining brain CT scans for all patients with new onset of nonfebrile seizures is unjustified. History and physical examination are sufficient to identify those patients for whom such studies are likely to be appropriate. Emergent CT is not indicated for patients with no known seizure risk factors, normal neurological examinations, no acute symptomatic cause other than fever, and reliable neurological follow-up. For these patients, referral to a pediatric neurologist for further workup, including electroencephalography and the more diagnostically valuable magnetic resonance imaging, would be more appropriate.

Epileptological emergencies in accident and emergency: a survey at St James's university hospital, Leeds

Many patients attending an Accident and Emergency (A&E) department with seizures never come into contact with a neurological service. This survey was designed to find out how many patients with epileptological emergencies come to A&E and how they are managed. Cases were identified using the computerized A&E database. The A&E records of all adult patients attending the casualty department at St James's University Hospital with emergencies related to epilepsy between 1 April and 30 September 1998 were reviewed retrospectively. Out of a total of 36 024 adults attending A&E, 190 were related to epileptological emergencies. A problem relating to a previously recognized seizure disorder was the commonest reason for attendance. Patient management was highly variable and often suboptimal. Descriptions of seizure semiology and examination findings were frequently deficient. Up to 37.5 mg of diazepam, in up to five boluses, was given. Twenty per cent of patients with a diagnosis of status epilepticus were discharged home after diazepam treatment. Neurologists only became involved in 24.2% of cases. Epileptological emergencies only make up a small proportion of cases seen in adult A&E departments. Treatment and referral guidelines should be agreed between A&E staff and neurologists. The communication between general, specialist and acute services needs to be improved.

Evaluation of the patient with seizures: an evidence based approach

Statistics tell us that as many as 1 in 20 members of the population will suffer a seizure at some point in their lifetime, a figure which becomes even more likely if one lives to the age of 80. Thus, a careful evidence based approach to the patient with seizure is immensely useful to the emergency physician. The authors evaluate current studies on the subject, discuss seizures as they relate to specific patient groups, and, ultimately, make recommendations on this important subject.

Emergency brain computed tomography in children with seizures: who is most likely to benefit?

OBJECTIVE

To determine whether the recently published guidelines on neuroimaging in patients with new-onset seizures are applicable to children.

METHODS

We carried out a retrospective analysis of 107 neurologically normal children (excluding children with simple febrile seizures) who had undergone neuroimaging when they presented to the emergency department with a possible "first seizure."

RESULTS

Eight of the 107 children had nonepileptic events (gastroesophageal reflux, syncopal event, rigor). Of the remaining 99 children, 49 had provoked seizures (complicated febrile seizure, meningo-encephalitis, toxic or metabolic abnormalities), and 50 had unprovoked seizures. A total of 19 children had brain abnormalities identified on computed tomography (CT) scan; 7 received further investigation or intervention as a result of CT scan findings (2 with tumors, 3 with vascular anomalies, 1 with cysticercosis, and 1 with obstructive hydrocephalus). CT scan abnormalities requiring treatment or monitoring were more frequently seen in children with their first unprovoked seizure (P < .01) and in those children whose seizure onset had been focal or who had focal abnormalities identified on postictal neurologic examination (P < .04).

CONCLUSION

In a child, a seizure in the setting of a fever rarely indicates the presence of an unexpected CT scan lesion requiring intervention.

New-onset generalized seizures in patients with AIDS presenting to an emergency department

OBJECTIVE

To determine the etiology of new-onset generalized seizures in patients with AIDS presenting to an ED. Patients without HIV infection with a first-time seizure were used as a comparison group. With these data, the current American College of Emergency Physicians (ACEP) guidelines on the workup of new-onset seizures were applied to determine whether they could safely be used in patients with AIDS.

METHODS

The authors conducted a retrospective review of all patients with new-onset generalized seizures who presented to an academic medical center hospital ED in New York City over 2 years. A standard ED medical evaluation with history, physical examination, and routine laboratory studies-including at least a panel 7 chemistry, serum magnesium, and complete blood count-was performed.

RESULTS

The causes of new-onset seizures in 26 patients with AIDS were idiopathic (8), HIV encephalopathy (8), CNS toxoplasmosis (5), alcohol withdrawal (2), progressive multifocal leukoencephalopathy (2), and CNS lymphoma (1). In 120 patients without HIV infection, idiopathic (43) and alcohol withdrawal (29) were the most common diagnoses. Six patients with AIDS had CNS lesions necessitating immediate admission to the hospital (5 with toxoplasmosis and 1 with lymphoma). Only 2 of 6 had findings on initial ED examination that would have suggested admission under current guidelines written for patients without HIV infection. The 4 patients with no findings were 3 with CNS toxoplasmosis and 1 with CNS lymphoma.

CONCLUSION

Four of 26 AIDS patients with immediately treatable CNS lesions could have been sent home for outpatient evaluation of their seizures on the basis of current guidelines for non-HIV-infected patients. However, the updated 1997 ACEP guidelines now include emergent brain neuroimaging studies on patients who have or are suspected of having AIDS. This study helps to strengthen this recommendation. Based on these findings, the authors suggest a neuroimaging study with a lumbar puncture, if indicated, in the ED or inpatient admission workup for all patients with AIDS or suspected AIDS presenting with new-onset generalized seizures.

The single seizure. To treat or not to treat?

It is generally accepted that anticonvulsant therapy should be offered once a patient has experienced 2 or more seizures. However, there is controversy over whether treatment should be offered after a single seizure. The type of epileptic event that has occurred may determine whether or not a single episode will bring the individual to medical attention. In individuals who experience a single seizure, there is significantly increased risk of recurrence if neurological or paroxysmal electroencephalogram abnormalities are present or if the seizure is partial. Anticonvulsant therapy, if taken as prescribed after a single seizure, will substantially reduce the risk of seizure recurrence. Unless a further seizure would hold little disadvantage, early treatment probably offers distinctly more benefit than hazard. No data are available to indicate the most appropriate duration of therapy after a single seizure.

Adult first generalized seizure: etiology, biological tests, EEG, CT scan, in an ED

The purpose of this study was to evaluate adult first seizures in an emergency department by analyzing etiologic and epidemiological data and studying the usefulness of biological screening, electroencephalogram (EEG), and cerebral computed tomography (CT) scan. This was a retrospective study of a 3-year period during which 247 patients were admitted to an emergency department for a first generalized seizure. A CT scan had been performed in 247 patients and an EEG in 209. Etiologies were found to be (1) unknown, (2) alcohol abuse, (3) stroke, and (4) tumor. Early recurrence rate was 18.5%. EEG was of low interest in emergency. The rate of cerebral focal lesions on CT scan was significantly lower when both examination results and EEG were normal. The rate of metabolic abnormalities was 4.9%. It was concluded that (1) a short hospitalization is advisable because of recurrences, (2) recurrence rate does not increase significantly in patients with focal cerebral lesion, (3) metabolic screening is necessary, and (4) CT scan will be an outpatient procedure for most patients.

Indication for computed tomography of the brain in patients with first uncomplicated generalised seizure

OBJECTIVES

To assess the yield of emergency computed tomography of the brain in patients with a first generalised epileptic seizure and to evaluate a four item screening questionnaire on alcohol misuse (CAGE questionnaire) as a triage tool to avoid unnecessary scans in cases of seizures related to withdrawal from alcohol.

DESIGN

Prospective, observational.

SETTING

Medical casualty unit in a university hospital.

PATIENTS

119 adult patients presenting to casualty within one hour of a generalised seizure.

MEASUREMENTS

A clinical examination focusing on focal neurological symptoms, the CAGE questionnaire, and computed tomography of the brain with contrast enhancement.

RESULTS

Computed tomography showed a focal, structural lesion of the brain in 40 patients (34% (95% confidence interval 25% to 42%)). In 20 patients (17% (10% to 24%)) an important therapeutic intervention resulted. The presence of a focal neurological deficit had a sensitivity of 50% and a specificity of 89% in predicting focal lesions on computed tomography. Answering "yes" to fewer than two CAGE questions had a sensitivity of 90% and specificity of 44% in identifying patients with focal computed tomography lesions. Focal lesions were not detected on computed tomography in any of the 35 patients (0% (0% to 10%)) who showed no focal neurological symptoms and answered "yes" to two or more CAGE questions.

CONCLUSIONS

The diagnostic yield of computed tomography of the brain in adults after a first generalised seizure is high. Combined with the clinical examination, the CAGE questionnaire can reliably identify patients with uncomplicated seizures related to withdrawal from alcohol, in whom computed tomography may not be absolutely necessary.