Nonconvulsive status epilepticus during cephalosporin therapy

Cephalosporins may induce nonconvulsive status epilepticus (NCSE), a potentially reversible condition. Despite the wide use of these antibiotics, there are only few reported cases, because this condition is probably underestimated. We report two new cases of NCSE occurring during treatment with cefepime and ceftazidime, and emphasize the utility of emergent electroencephalogram in patients with an acute altered state of consciousness while receiving treatment with cephalosporins, particularly when there is evidence of impaired renal function.     

Epilepsy and sleep: with special reference to nonconvulsive status epilepticus with continuous diffuse spike-waves during slow-wave sleep

There are numerous important problems concerning relationship between epilepsy and sleep. To clarify the clinical significance and pathophysiology of the nonconvulsive status epilepticus with continuous diffuse spike-waves during slow-wave sleep (CSWS) in EEG, this study was carried out on seven cases each of epilepsies with electrical status epilepticus during slow sleep (ESES) and with peculiar type of nonconvulsive status epilepticus in childhood (PNSE) and four cases of atypical benign partial epilepsy (ABPE). Mental deterioration was most frequently observed in ESES, less in PNSE but none in ABPE. In both ESES and PNSE, mentally deteriorated cases showed suppression of CSWS at significantly later ages than those without deterioration. And spike-wave indices during slow-wave sleep, which were the highest in ESES and lower in PNSE and ABPE, also had a strong relation to mental deterioration. In these three disorders, both clinical seizures and CSWS were suppressed at or before 16 years of age, although they were intractable before adolescence. This finding indicated age dependent evolutions of the three disorders. Coherence and phase analysis of CSWS was undertaken to differentiate primary and secondary bilateral synchrony in seven cases of these three disorders, which have both features of generalized and partial epilepsies. This analysis disclosed secondary bilateral synchrony as the nature of CSWS in six cases. And this analysis method was considered to provide a clue to their pathophysiology. Thus, in these disorders, importance of early diagnosis by EEG including deep sleep and early treatment was recognized.     

非惊厥性癫(癎)持续状态

非惊厥性癫(癎)持续状态(NCSE)系临床常见但易忽视的癫(癎)持续状态(SE)发作类型,据估计,占所有癫(癎)持续状态的20%～50%.2004年,英国癫(癎)研究基金会(ERF)将非惊厥性癫(癎)持续状态定义为:由于持续性癫(癎)样脑电活动导致的一系列非惊厥临床征象[1].     

Nonconvulsive status epilepticus

Nonconvulsive status epilepticus (NCSE) is a heterogeneous disorder with multiple subtypes. Although attempts have been made to define and classify this disorder, there is yet no universally accepted definition or classification that encompasses all subtypes or electroclinical scenarios. Developing such a classification scheme is becoming increasingly important, because NCSE is more common than previously thought, with a bimodal peak, in children and the elderly. Recent studies have also shown a high incidence of NCSE in the critically ill. Although strong epidemiological data are lacking, NCSE constitutes about 25-50% of all cases of status epilepticus. For the purposes of this review, we propose an etiological classification for NCSE including NCSE in metabolic disorders, NCSE in coma, NCSE in acute cerebral lesions, and NCSE in those with preexisting epilepsy with or without epileptic encephalopathy. NCSE is still underrecognized, yet potentially fatal if untreated. Diagnosis can be established using an electroencephalogram (EEG) in most cases, sometimes requiring continuous monitoring. However, in comatose patients, diagnosis can be difficult, and the EEG can show a variety of rhythmic or periodic patterns, some of which are of unclear significance. Although some subtypes of NCSE are easily treatable, such as absence status epilepticus, others do not respond well to treatment, and debate exists over how aggressively clinicians should treat NCSE. In particular, the appropriate treatment of NCSE in patients who are critically ill and/or comatose is not well established, and large-scale trials are needed. Overall, further work is needed to better define NCSE, to determine which EEG patterns represent NCSE, and to establish treatment paradigms for different subtypes of NCSE.     

Scalp-recorded high-frequency oscillations in childhood epileptic encephalopathy with continuous spike-and-wave during sleep with different etiologies

Objective

To investigate high-frequency oscillations (HFOs) in epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS) with different etiologies.

Nonconvulsive status epilepticus in patients with cancer

Patients with systemic cancer may have altered mental status without evidence of metastases, strokes, or metabolic encephalopathies. Six such patients are described whose EEGs showed continuous generalized epileptiform discharges in the absence of clinical signs of seizures. Two patients had never had any clinical evidence of seizures and four had seizures that were thought to have stopped before the EEG. Three patients were confused and three were stuporous or comatose. In some patients the nonconvulsive epileptic activity may have been directly related to the cancer; three had findings suggestive of possible paraneoplastic encephalopathies. Anticonvulsants led to an improved mental status in four patients, but all except one died. Nonconvulsive generalized status epilepticus may explain altered mental status in some patients with cancer and anticonvulsant medication treatment can be beneficial.     

Nonconvulsive status epilepticus and coma

Nonconvulsive status epilepticus (NCSE) in a comatose patient cannot be diagnosed without electroencephalography (EEG). In many advanced coma stages, the EEG exhibits continuous or periodic EEG abnormalities, but their causal role in coma remains unclear in many cases. To date there is no consensus on whether to treat NCSE in a comatose patient in order to improve the outcome or to retract from treatment, as these EEG patterns might reflect the end stages of a dying brain. On the basis of EEG, NCSE in comatose patients may be classified as generalized or lateralized. This review aims to summarize the ongoing debate of NCSE and coma and to critically reassess the available literature on coma with epileptiform EEG pattern and its prognostic and therapeutic implications. The authors suggest distinguishing NCSE proper and comatose NCSE, which includes coma with continuous lateralized discharges or generalized epileptiform discharges (coma‐LED, coma‐GED). Although NCSE proper is accompanied by clinical symptoms suggestive of status epilepticus and mild impairment of consciousness, such as in absence status or complex focal status epilepticus, coma‐LED and coma‐GED represent deep coma of various etiology without any clinical motor signs of status epilepticus but with characteristic epileptiform EEG pattern. Hence coma‐LED and coma‐GED can be diagnosed with EEG only. Subtle or stuporous status epilepticus and epilepsia partialis continua–like symptoms in severe acute central nervous system (CNS) disorders represent the borderland in this biologic continuum between NCSE proper and comatose NCSE (coma‐LED/GED). This pragmatic differentiation could act as a starting point to solve terminologic and factual confusion.     

Nonconvulsive status epilepticus in patients with brain tumors

PurposeThe prevalence of nonconvulsive status epilepticus (NCSE) in brain tumor patients is unknown. Since NCSE has been associated with significant mortality and morbidity, early identification is essential. This study describes the clinical and EEG characteristics, treatment, and outcome in brain tumor patients with NCSE.MethodAll patients admitted to Mount Sinai Hospital from 2009 to 2012 with an ICD-9 brain tumor code were cross-referenced with the epilepsy department's database. EEGs from matching patients were reviewed for NCSE. Relevant information from the medical records of the patients with NCSE was extracted.Results1101 brain tumor patients were identified, of which 259 (24%) had an EEG and 24 (2%) had NCSE. The vast majority of seizures captured were subclinical with 13 patients (54%) having only subclinical seizures. Treatment resolved the NCSE in 22 patients (92%) with accompanying clinical improvement in 18 (75%) of those patients. Tumor recurrence or progression on MRI was associated with decreased 2-month survival (75% mortality, p = 0.035) compared to stable tumors (20% mortality). Patients with metastatic disease had median survival from tumor diagnosis of 1.2 months.ConclusionNCSE in brain tumor patients may be under diagnosed due to the frequent lack of outward manifestations and highly treatable with improvement in the majority of patients. NCSE patients with progressing brain lesions, tumor recurrence, or metastatic disease are at serious risk of mortality within 2 months. Continuous EEG monitoring in brain tumor patients with recent clinical seizures and/or a depressed level of consciousness may be critical in providing appropriate care.     

Nonconvulsive status epilepticus on treatment with levetiracetam

In several studies the efficacy and tolerability of levetiracetam (LEV) have been demonstrated. We report two patients who developed nonconvulsive status epilepticus on treatment with LEV. Both patients never experienced status epilepticus before. One patient had a symptomatic epilepsy with complex partial seizures following radiotherapy of astrocytoma in 1985; the second patient had complex partial seizures due to mesial temporal sclerosis. Both patients received LEV 2000 mg/day. We postulate a correlation between occurrence of nonconvulsive status and treatment with LEV. This has not been described before apart from a single report of mentally retarded patients with status epilepticus on high dosages of LEV.     

Focal polymicrogyria,continuous spike-and-wave discharges during slow-wave sleep and Cohen syndrome: a case report

Cohen syndrome is a rare genetic disorder consisting of truncal obesity, hypotonia, mental retardation, characteristic facial appearance and ocular anomalies. Other diagnostic clinical features include narrow hands and feet, low growth parameters, neutropenia and chorioretinal dystrophy. Here, we report an 18-year-old male with Cohen syndrome associated with focal polymicrogyria and continuous spike-and-wave discharges during slow-wave sleep.     

Nonconvulsive status epilepticus after temporal lobectomy

Acute brain injury can cause nonconvulsive status epilepticus (NCSE). However, this condition has not been reported immediately after brain surgery. We describe a patient who had NCSE in the recovery room after an otherwise successful right temporal lobectomy and emphasize the usefulness of electroencephalography in this situation.     

Nonconvulsive status epilepticus and neurodevelopmental delay

Nonconvulsive status epilepticus is characterized by continuous or near continuous epileptiform discharges on electroencephalography without overt motor or sensory phenomena. It is a symptomatic condition related to a disease such as epileptic encephalopathy or a metabolic disorder. Children with isolated nonconvulsive status epilepticus rarely present with global neurodevelopmental delay. This report describes an 18-month-old male who presented with global neurodevelopmental delay and decreased alertness in whom electrical status epilepticus during sleep, which is a form of nonconvulsive status epilepticus, was determined. Metabolic investigations and cranial magnetic resonance imaging were normal. He began to achieve developmental milestones after treatment with valproic acid. Although rare, pediatric neurologists and pediatricians must be aware of this condition in making the differential diagnosis of global neurodevelopmental delay and decreased alertness.     

Nonconvulsive status epilepticus following cerebral angiography

A 64-year-old man developed lethargy and aphasia immediately following cerebral arteriography with iothalamate meglumine. An electroencephalogram showed continuous epileptiform activity. The patient was treated with intravenous phenytoin with complete resolution of clinical symptoms and electroencephalographic epileptiform abnormalities. The diagnosis of nonconvulsive status epilepticus should be considered in cases of altered consciousness following cerebral arteriography.     

Nonconvulsive status epilepticus of frontal origin

OBJECTIVES: To determine the electroclinical characteristics and causative factors of nonconvulsive status epilepticus (NCSE) of frontal origin. METHODS: The authors conducted a 5-year prospective study. RESULTS: Ten patients were studied (seven men, three women; mean age, 56.4 years). Six patients did not have previous epilepsy. The mean diagnostic delay was 48 hours (range, 3 to 96 hours). Two types of frontal NCSE were identified. In type 1 (n = 7), mood disturbances with affective disinhibition or affective indifference were associated with subtle impairment of cognitive functions without overt confusion. EEG showed a unilateral frontal ictal pattern and normal background activity. In type 2 (n = 3), impaired consciousness was associated with bilateral, asymmetric frontal EEG discharges occurring on an abnormal background. Ictal and postictal 99mTc hexamethyl propylene amine oxime (HMPAO) SPECT was performed in five patients and showed unilateral or bilateral frontal HMPAO uptake that aided localization, especially in type 2 NCSE of frontal origin. Etiologies included a focal frontal lesion in six patients (three of which were tumors), neurosyphilis, and nonketotic hyperglycemia. Eight patients did not respond to initial IV benzodiazepine (BZ), but IV phenytoin controlled six patients successfully. The immediate outcome was favorable in all patients. There was no long-term recurrence of SE in seven patients. CONCLUSIONS: NCSE of frontal origin is a heterogeneous syndrome. Some cases are best described as simple partial NCSE, others as complex partial SE, and there are forms that overlap with absence SE. Emergency EEG and neuropsychological assessment are diagnostic, and SPECT may be useful. Many patients may not respond to IV BZ.