In Whom Does Status Epilepticus Occur: Age-Related Differences in Children

: Purpose: Status epilepticus (SE) is an uncommon but potentially life-threatening seizure. It is most common in children. Little is known about the differences within the pediatric age group in terms of the type of patient seen with SE. Methods: We analyzed the records of 394 children aged 1 month to 16 years who were part of two large studies of pediatric SE conducted in Bronx, New York, and Richmond, Virginia. The 394 children had a mean age of 4.4 years and included 349 (89%) with an initial episode of SE. Results: Status epilepticus was most common in younger children with > 40% of cases occurring in those younger than 2 years. The distribution of causes was highly age dependent. More than 80% of children younger than 2 years had SE of febrile or acute symptomatic origin, whereas cryptogenic and remote symptomatic causes were most common in older children (p <0.001). One hundred fifty-eight (40%) of the cases were known to be previously neurologically abnormal, including 35 (21%) of 169 younger than age 2 years and 123 (55%) of 225 older than 2 years (p <0.001). One hundred seventy-seven (45%) children had a history of seizures including 142 (41%) of the 349 children with a first episode of SE. A history of seizures was present in 34 (20%) of those younger than 2 years and 143 (64%) of those older than 2 years (p < 0.001). The effect of age remained significant even when the analysis was limited to those with SE of cryptogenic or remote symptomatic origin. Conclusions: There is a strong effect of age on the frequency and etiology of SE, as well as on the type of child who has SE. In young children, SE occurs primarily in children who are neurologically normal and with no history of unprovoked seizures. In older children, SE occurs primarily in those who are known to have prior unprovoked seizures and who are often also neurologically abnormal.     

De Novo Status Epilepticus as the Presenting Sign of Neurosyphilis

Summary: Although the incidence of seizures in neurosyphilis ranges from 14 to 60%, status epilepticus (SE) as a presenting complaint of neurosyphilis is definitely rare. A 44-year-old human immunodeficiency virus (H1V)-negative man with no history of epilepsy suddenly presented with acute mental confusion and was diagnosed as having a de novo complex partial nonconvulsive SE. Cerebrospinal fluid (CSF) findings, neuroimaging, and clinical course indicated that SE was the presenting symptom of an undiagnosed syphilitic meningovasculitis. The case is presented with a review of previous reports to emphasize the differential features and to underscore the importance of considering neurosyphilis among the possible causes of de novo SE.     

Persistent Nonconvulsive Status Epilepticus After the Control of Convulsive Status Epilepticus

Summary: Purpose: Convulsive status epilepticus (CSE) is a major medical and neurological emergency that is associated with significant morbidity and mortality. Despite this high morbidity and mortality, most acute care facilities in the United States cannot evaluate patients with EEG monitoring during or immediately after SE. The present study was initiated to determine whether control of CSE by standard treatment protocols was sufficient to terminate electrographic seizures. Methods: One hundred sixty-four prospective patients were evaluated at the Medical College of Virginia/VCU Status Epilepticus Program. Continuous EEG monitoring was performed for a minimum of 24 h after clinical control of CSE. SE and seizure types were defined as described previously. A standardized data form entry system was compiled for each patient and used to evaluate the data collected. Results: After CSE was controlled, continuous EEG monitoring demonstrated that 52% of the patients had no after-SE ictal discharges (ASIDS) and manifested EEG patterns of generalized slowing, attenuation, periodic lateralizing epileptiform discharges (PLEDS), focal slowing, and/or burst suppression. The remaining 48% demonstrated persistent electrographic seizures. More than 14% of the patients manifested nonconvulsive SE (NCSE) predominantly of the complex partial NCSE seizure (CPS) type (2). These patients were comatose and showed no overt clinical signs of convulsive activity. Clinical detection of NCSE in these patients would not have been possible with routine neurological evaluations without use of EEG monitoring. The clinical presentation, mortality, morbidity, and demographic information on this population are reported. Conclusions: Our results demonstrate that EEG monitoring after treatment of CSE is essential to recognition of persistent electrographic seizures and NCSE unresponsive to routine therapeutic management of CSE. These findings also suggest that EEG monitoring immediately after control of CSE is an important diagnostic test to guide treatment plans and to evaluate prognosis in the management of SE.     

Oculoclonic Status Epilepticus

Continuous oculoclonic status epilepticus occurred for 90 min in a 4-year-old girl. The seizure consisted of continuous contralateral horizontal nystagmus concurrent with left occipital spike discharges, occasional vomiting and no loss of consciousness. Oculoclonic status epilepticus may be a variant form of versive status epilepticus.     

Determinants of Mortality in Status Epilepticus

Summary: Using univariate and multivariate regression analysis, we studied seizure duration, seizure type, age, etiologies, other clinical features, and mortality among 253 adults with status epilepticus (SE) admitted to the Medical College of Virginia. Cerebral vascular disease and discontinuation of antiepileptic drugs (AEDs) were the most prominent causes of SE, each accounting for ∼22% of all patients in the series. The other principle etiologies were alcohol withdrawal, idiopathic, anoxia, metabolic disorders, hemorrhage, infection, tumor, drug overdose, and trauma. When the patients were divided into two groups, the group with SE lasting < 1 h had a lower mortality as compared with seizure duration ≥ 1 h. Low mortality rates were noted in alcohol and AED discontinuation etiologies. Anoxia and increasing age were significantly correlated with higher mortality. The mortality rates of partial and generalized SE were not significantly different. Race and sex did not affect mortality significantly. Our findings represent the first multivariate analysis of predictive indicators of mortality in SE and demonstrate that specific factors influence mortality rate in SE.     

Prolonged Focal Cerebral Edema Associated with Partial Status Epilepticus

Following several days of partial status epilepticus, three patients developed striking focal cerebral edema as demonstrated by computed axial tomography (CT) scan. An angiogram done in one patient showed a capillary blush and early cortical draining veins in the corresponding area. All patients developed severe focal neurological deficit which resolved as the edema improved, and this was demonstrated on serial CT scans (at 6 months, 1 month, and 2 months, respectively). In the first patient, an underlying tumor, and in the second and third, vascular occlusions, were suspected because we were not aware that edema due to status epilepticus could produce changes of such intensity and duration. The neurological disability after the partial status was long-lasting but reversed completely in our patients. Maximal radiological changes occurred in the area of maximal epileptic discharge. Minimal atrophic changes persisted in two of the three patients. The clinical, CT scan, and angiographic findings suggest that partial status epilepticus can be associated with abnormal vascular permeability leading to prolonged focal cerebral edema. Similar pathophysiology of lesser intensity may be responsible for shorter postictal neurological deficits. Awareness of this clinical and radiological entity should avoid misdiagnosis of cerebral tumor or infarction.     

De Novo Absence Status Epilepticus as a Benzodiazepine Withdrawal Syndrome

Summary: A 67-year-old woman with a history of psychotropic drug abuse developed confusion. EEG was consistent with absence status epilepticus (AS). Intravenous (i.v.) flumazenil 1 mg, a benzodiazepine antagonist with anticonvulsant properties, increased both confusion and paroxysmal activity. Complete resolution was obtained after diazepam was administered i.v., and the patient then admitted that she had abruptly discontinued long-standing treatment with carpipramine, amitryptiline, bromazepam, and flunitrazepam. The aggravating effect of flumazenil indicates that benzodiazepine withdrawal was probably the elective triggering factor of this de novo absence status epilepticus.     

Aphasia as the Sole Manifestation of Simple Partial Status Epilepticus

Aphasia due to simple partial status epilepticus is rare, particularly in the absence of a seizure history. No previous report describes acute aphasia as the sole clinical manifestation of EEG-monitored status epilepticus, with prompt resolution with treatment. We report a 45-year-old man with a left temporal glioblastoma who acutely developed a global aphasia, during which an EEG revealed continual repetitive sharp waves emanating from the left hemisphere. After injection of i.v. diazepam, the EEG seizure activity ceased, and the patient's language output returned to preseizure levels.     

癫痫持续状态的定义演变

癫痫持续状态是神经内科常见的急危重症。对癫痫持续状态概念的界定是进行临床诊疗 和科学研究的基础,随着癫痫持续状态病理生理机制研究的深入,其定义也在不断地修订与完善, 由抽象到具体,由惊厥到非惊厥,癫痫发作持续时间逐渐严谨且更加强调难治性的概念。本文着重 回顾癫痫持续状态的定义演变历程。     

Physiologic Consequences of Status Epilepticus

Summary: Prolonged seizures produce central nervous system damage. Physiologic consequences of status epilepticus may exacerbate this damage or may mislead the physician into making inappropriate therapeutic decisions. Status results in an elevation of body temperature, an increase in the peripheral white cell count, and often a transient pleocytosis in the spinal fluid. A marked metabolic acidosis occurs routinely. Prominent elevations in plasma hormonal concentrations occur as well. Epinephrine levels are in the arrhythmogenic range and could play a role in sudden death. Transient but marked pressure responses occur in the systemic and pulmonary circulations. Pulmonary edema may result from these pressure transients.     

Focal Status Epilepticus: Clinical Features and Significance of Different EEG Patterns

PURPOSE: Focal status epilepticus is typically diagnosed by the observation of continuous jerking motor activity, but many other manifestations have been described. EEG evidence of focal status may take several forms, and their interpretation is controversial. We detailed the clinical spectrum of focal status in patients diagnosed by both clinical deficit and EEG criteria and contrasted clinical manifestations in patients with different EEG patterns. METHODS: Patients were diagnosed with a neurologic deficit and discrete recurrent focal electrographic seizures or rapid, continuous focal epileptiform discharges on EEG. Clinical findings were determined by chart review. RESULTS: Of 41 patients with focal status, acute vascular disease was the cause in 21; 10 of 41 had exacerbations of prior epilepsy. A variety of clinical seizure types occurred, both before and after the EEG diagnosis, but the diagnosis was not expected in 28 patients before the EEG. Three had no obvious clinical seizures. Focal motor seizures and an abnormal mental status were the most common manifestations at the time of the EEG. With antiepileptic drugs, almost all had control of clinical seizures, and most improved in mental status. Patients with rapid continuous focal epileptiform discharges were nearly identical in presentation, likelihood of diagnosis, subsequent seizures, response to medication, and outcome to those with discrete seizures on EEG. CONCLUSIONS: Focal status epilepticus may be seen with a wide variety of clinical seizure types or without obvious clinical seizures. The diagnosis is often delayed or missed and should be considered after strokes or clinical seizures when patients do not stabilize or improve as expected. The diagnosis should be made equally whether patients have discrete electrographic seizures or continuous rapid focal epileptiform discharges on the EEG, and the same response to medications and outcome should be anticipated for the two groups.     

Nonconvulsive Status Epilepticus: EEG Analysis in a Large Series

Summary: We analyzed EEG characteristics comprehensively in a large series of nonconvulsive status epilepticus (NCSE) cases. Eighty-five ictal episodes in 78 patients were analyzed. The ictal discharges were generalized (group G) in 59 episodes (69%), diffuse with focal predominance (group GF) in 15 (18%), and focal (group F) in 11 (13%). The morphologies and patterns of persistence varied greatly. Frequency of ictal discharge was also variable and was almost always <3 Hz. Demonstration of focal epileptic features in response to intravenous (i.v.) diazepam (DZP) and the presence of interictal focal epileptiform discharges in some cases in groups G and GF suggested possible focal onset secondarily generalized in these cases. This study suggests that electrographically NCSE is a highly heterogeneous epileptic state, and i.v. DZP may serve as a valuable diagnostic tool in differentiating generalized from focal onset NCSE.     

Aphasic or amnesic status epilepticus detected on PET but not EEG

Purpose:   To describe five patients with ictal aphasia and one patient with ictal amnesia, who had focal positron emission tomography (PET) hypermetabolism but no clear ictal activity on electroencephalography (EEG).
Methods:   ¹⁸F-Fluorodeoxyglucose (FDG)–PET scans with concomitant EEG were obtained in five patients with suspected ictal aphasia or ictal amnesia without ictal activity on EEG. We reviewed medical history, EEG, imaging data, and treatment outcome.
Results:   Brain magnetic resonance imaging (MRI) showed no structural abnormalities in any of the patients. EEG showed left temporal irregular delta activity in three patients, with aphasia and nonspecific abnormalities in two other patients, all without clear ictal pattern. All patients demonstrated focal hypermetabolism on PET scan. The hypermetabolism was in the left frontotemporal region in patients with ictal aphasia and in the bilateral hippocampal region in the patient with amnesia. Three patients who received intravenous benzodiazepines during their episodes had transient clinical improvement. With antiepileptic drug (AED) treatment, symptoms gradually resolved in all patients. Concomitant resolution of PET hypermetabolism was documented in three patients who had follow up scans. One patient with ictal aphasia later developed recurrent episodes, each with recurrent PET hypermetabolism. This patient and one other patient required immune-modulating therapy in addition to AEDs.
Discussion:   FDG-PET imaging should be considered as a diagnostic tool in patients with suspected ictal aphasia or amnesia, who fail to show clear evidence of ictal activity on EEG.     

Clinical Characteristics and Treatment Outcomes of De Novo Nonconvulsive Status Epilepticus: A Retrospective Study

Background and PurposeNonconvulsive status epilepticus (NCSE) is challenging to diagnose. This study aimed to describe and classify the clinical features and electroencephalography (EEG) findings of patients with de novo NCSE and to correlate them with clinical outcomes.MethodsWe retrospectively reviewed the medical and EEG records of patients admitted to our institution with altered mentation and EEG abnormalities from January 1, 2013 to December 31, 2018. We evaluated premorbid modified Rankin Scale (mRS) scores, underlying disorders, precipitating factors, clinical manifestations, laboratory tests, and outcomes after a 3-month follow-up. Patients who met the Salzburg Consensus Criteria for NCSE were categorized into good-outcome and poor-outcome groups. A good outcome was defined as 1) clinical and electrographic seizures ceasing after treatment, and 2) an mRS score of ≤2 or remaining unchanged during the 3-month follow-up. A poor outcome was defined as 1) death, 2) seizures continuing despite treatment, or 3) a follow-up mRS score of ≥3 in a patient with a premorbid mRS score of ≤2, or a follow-up mRS score that increased in a patient with a premorbid mRS score of ≥3.ResultsThe 48 included patients comprised 37 categorized into the good-outcome group and 11 into the poor-outcome group. The presence of acute metabolic disturbances was significantly correlated with poor outcome (p=0.036), while the other analyzed variables were not significantly correlated with outcomes.ConclusionsAcute metabolic disturbances in NCSE are associated with poor outcomes. Adequate treatment of underlying reversible disorders alongside controlling seizures is critical for patients with NCSE.     

Two Patients with Juvenile Myoclonic Epilepsy and Nonconvulsive Status Epilepticus

We report 2 girls, aged 10 and 13 years, with juvenile myoclonic epilepsy (JME) who had episodes of nonconvulsive status epilepticus (NCSE). Symptoms included only mild lethargy, slow responses, and trembling of the eyelids. There was no ataxia or myoclonus of the limbs or body, and they were always able to respond. Electroencephalograms during these episodes showed almost continuous generalized polyspike-waves in both patients. Patients with JME can develop NCSE, which may be overlooked because of the subtle clinical symptoms.     

Short-Term Mortality After a First Episode of Status Epilepticus

Summary: Purpose: Studies evaluating short-term mortality among people who experience status epilepticus (SE) have produced conflicting results. Most studies are derived from clinical series with results affected by unspecified follow-up period and select referral of cases. This study was planned to evaluate short-term mortality after a first episode of SE. Methods: We performed a population-based retrospective cohort study to determine the short-term mortality following a first episode of SE. Between January 1,1965 and December 31, 1984, we studied all first episodes of a febrile SE who received medical attention in Rochester, Minnesota. Cases were followed until death or end of the study (February 1996). Results: Mortality within the first 30 days was 19% (38 deaths out of 201 incident SE). Thirty-four deaths (89%) occurred among those with non febrile acute symptomatic SE, while 4 deaths (11%) occurred among those with unprovoked SE. Within the acute symptomatic group, after adjusting for age, there was a decreased risk of death in women (RR = 0.4; 95% CI: 0.2–0.9). No effect of duration or seizure type was shown after adjusting for other risk factors. Conclusions: One out of 5 subjects with SE died within the first 30 days. Short-term mortality is associated with the presence of an underlying acute etiology. Among acute symptomatic cases, women had a decreased risk of dying.