Nonconvulsive status epilepticus presenting as epileptic nystagmus in a patient with herpes encephalitis

Epileptic nystagmus (EN) is characterized by rhythmic ocular oscillations or quick, repetitive eye movements secondary to seizure activity. The fast component of EN is known to be contralateral to the epileptogenic focus. There are few reports EN occurring patients in nonconvulsive status epilepticus (NCSE). We report such a patient in the setting of herpes encephalitis.     

De-novo simple partial status epilepticus presenting as Wernicke's aphasia

Language disturbances manifesting as brief periods of speech arrest occur with seizures originating in the frontal or temporal lobes. These language disturbances are usually present with other features of seizures or may occur in an episodic fashion suggesting their likely epileptic origin. Sustained but reversible aphasia as the sole manifestation of partial status epilepticus is rare, particularly without a history of prior seizures. A few cases have been described in the literature where Broca's or mixed aphasia seems to be more common than Wernicke's aphasia. Here we describe a patient who presented with Wernicke's aphasia secondary to simple partial status epilepticus but without any other features of seizures. The diagnosis was confirmed on EEG and the aphasia reversed after antiepileptic treatment.     

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].     

Primary progressive aphasia presenting as conduction aphasia.

We report a case of a woman with primary progressive aphasia (PPA) who presented with conduction aphasia. A 60-year-old, right-handed, Japanese female suffering from progressive aphasia had difficulty in repeating words and phrases. She displayed phonemic paraphasias but had preserved comprehension and had no cognitive or behavior disorder for more than 6 years after the onset of the condition. She was able to continue to work successfully and to perform all her normal daily activities. T1-weighted magnetic resonance imaging revealed minute dilatation of the left inferior horn and sulci in the left hemisphere, and positron emission tomography revealed mild hypometabolism in the left supramarginal gyrus and its surrounding areas. Therefore, she was diagnosed as suffering from PPA presenting as conduction aphasia. We believe that the progressive conduction aphasia of the patient belongs to one of the fluent forms of PPA, and the ability to continue normal work along with the clinical portrayal of preserved memory and cognition skills may be features of a form of PPA presenting as conduction aphasia.     

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.     

Nonconvulsive status epilepticus on electroencephalography in a case with subacute sclerosing panencephalitis

Subacute sclerosing panencephalitis is a neurodegenerative disease with a poor prognosis. We report a case of a 5 1/2-year-old boy who had emotional lability, cognitive difficulties, and myoclonia after a mild closed head injury. The magnetic resonance image of the brain and computed tomographic scan of the head were normal. His electroencephalogram (EEG) showed continuous nonconvulsive status epilepticus activity, which could not be suppressed with intravenous diazepam. After treatment with phenytoin for 2 days, an EEG showed periodic high-amplitude sharp-and-slow-wave complexes, which were also not suppressed with intravenous diazepam. Since the patient had measles at 5 months of age, subacute sclerosing panencephalitis was considered, and the diagnosis was confirmed by the presence of measles antibodies in cerebrospinal fluid.     

Non-convulsive status epilepticus presenting with Wernicke's aphasia

Ictal aphasia in adults is a rare phenomenon. Most reported cases manifest with non-fluent (Broca) aphasia. Ictal fluent (Wernicke) aphasia is less common. We report a 47-year-old, right-handed woman that presented with recurrent episodes of non-convulsive seizures in the form of Wernicke's aphasia for 2 weeks. An MRI of the brain showed an old cerebral infarction in the left parieto-occipital area. Scalp EEG revealed continuous periodic sharp waves at the left temporal regions with diffusion to the whole left hemisphere and at occasions to the right. This is followed by variable periods of post ictal slowing. Recurrence of the described ictal pattern was noted. Management of status epilepticus was started in the form of intravenous diazepam and a loading dose of phenytoin and phenobarbitone. After treatment, she improved clinically and the EEG improved with disappearance of the left temporal ictal rhythm and normalization of the EEG background. Thus, establishing the diagnosis of non-convulsive partial status epilepticus manifesting as ictal aphasia.     

Nonconvulsive status epilepticus precipitated by carbamazepine presenting as dissociative and affective disorders in adolescents

Nonconvulsive status epilepticus can be confused with psychiatric disorders. Inappropriate drug treatment can represent a precipitating factor. We describe two patients with idiopathic generalized epilepsy in whom nonconvulsive status epilepticus, aggravated by carbamazepine, was misdiagnosed as psychiatric disorder. A 14-year-old girl experienced a tonic-clonic seizure at age 12 years preceded by monthly episodes of confusion with awkward behavior since age 9 years. She was treated with carbamazepine, and the episodes of confusion became more frequent, leading to a diagnosis of dissociative disorder. An electroencephalogram during one of these episodes revealed nonconvulsive status epilepticus. Substitution of carbamazepine with valproic acid controlled the episodes of status epilepticus. A 23-year-old woman presented at age 16 years with a tonic-clonic seizure. Since early adolescence, she had had episodes of depressive mood, worsening of school performances, and facial tics. Carbamazepine treatment caused worsening of the depressive episodes and facial tics. An electroencephalogram during a typical episode revealed nonconvulsive status epilepticus. Carbamazepine substitution with valproate led to seizure freedom and behavioral improvement. Nonconvulsive status epilepticus should be suspected and searched for in patients with epileptic seizures and ictal or fluctuating behavioral disorders.     

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 following metrizamide myelography

Epileptic seizures are a known complication of metrizamide myelography. To our knowledge, this is the first report of a case of nonconvulsive status epilepticus of the absence type following metrizamide myelography. There was symptomatic and electroencephalographic improvement after intravenous administration of antiepileptic drugs, and there was no neurological residual. Nonconvulsive status epilepticus should be considered when impairment of consciousness supervenes after radiographic procedures using metrizamide.     

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.     

Nonconvulsive status epilepticus after electroconvulsive therapy

SUMMARY: We describe three cases of nonconvulsive status epilepticus induced by electroconvulsive therapy (ECT). Nonconvulsive status epilepticus is an important differential diagnosis in patients who develop prolonged confusion after ECT. The present cases exemplify the difficulty in defining the diagnosis on the basis of the clinical manifestations. The application of electroencephalography is recommended in monitoring patients with prolonged confusion following ECT. Concurrent drug therapy and ECT is discussed.