F. Randi

EEG patterns and epileptic seizures in acute phase stroke.

Background: The rate of early post-stroke epileptic seizures ranges from 2 to 33%. This wide range is likely due to differences in study design, patient selection and type of neurophysiological monitoring. Electroencephalography (EEG), which is not used in the routine work-up of acute stroke, is the best neurodiagnostic technique for detecting epileptic activity, especially in patients with non-convulsive post-stroke epileptic activity. The aim of this study was to analyze patterns on EEGs performed within 24 h of stroke onset, and to investigate correlations between these patterns and the occurrence of early epileptic seizures and status epilepticus (SE), vascular risk factors, stroke subtypes and short-term outcome. Methods: We prospectively studied 232 patients (mean age 71 ± 12 years; 177 ischemic strokes and 55 hemorrhagic). EEG recording was performed within 24 h from hospitalization. The follow-up lasted 1 week. Results: Fifteen patients (6.5%) had early seizures within 24 h; 10 of these patients had focal SE with or without secondary generalization. EEG revealed sporadic epileptiform focal abnormalities in 10% and periodic lateralized epileptiform discharges (PLEDs) in 6%. SE was recorded in 71.4% of patients with PLEDs. At the multivariate analysis, only early epileptic manifestations (p < 0.001) were independently associated with PLEDs. Conclusions: Our study confirms that seizures are not frequent in the early phase of acute stroke and occur prevalently as focal SE at onset. EEG may help to detect specific patterns, such as PLEDs, that are closely related to early seizures. EEG monitoring should be performed in order to detect purely electrographic seizures.

Idiopathic late-onset absence status epilepticus: A case report with an electroclinical 14 years follow-up

Late-onset absence status epilepticus (ASE) may be observed in adult and elderly patients as a late complication of idiopathic generalized epilepsy or de novo, usually related to benzodiazepines withdrawal, alcohol intoxication or psychotropic drugs initiation, but without history of epilepsy. EEG may be highly heterogeneous, varying from the 3 to 3.5 Hz spike-wave discharges typical of idiopathic generalized epilepsy to asymmetric irregular sharp and slow wave complexes. We report the clinical and neurophysiologic 14 years follow-up of a now 86 years-old woman, in whom we observed--at the age of 72--an idiopathic late-onset ASE, with a good clinical response to lamotrigine monotherapy, but with the persistence over years of the same interictal 3-3.5 Hz spike-wave epileptic activity at EEG. This case is singular because, with the available long follow-up, indicates that idiopathic generalized epilepsy may also occur in the elderly, with a late-onset ASE presentation. In this condition, it is particularly important to underline the essential role of EEG (urgent and ambulatory) for the diagnosis, management and monitoring of the disease.

Reversible encephalopathy induced by cefoperazone: a case report monitored with EEG

In patients with an impaired state of consciousness, EEG is fundamental, a correct neurological work-up. Cephalosporins have been identified as a case of triphasic waves’ (TW) reversible encephalopathy. We report a case of an acute reversible encephalopathy with TWs during treatment with cefoperazone. We report the occurrence and regression of a confusional state with TWs encephalopathy at EEG after the administration of cefoperazone for urinary tract infection in a patient admitted for syncope. In conclusion, cefoperazone should be considered as a cause of toxic encephalopathy with EEG TWs, when there is a temporal relationship with its administration; EEG monitoring is useful in the neurological follow-up.

Non-convulsive status epilepticus characterised exclusively by a language disorder induced by non-ketotic hyperglycaemia

Non-ketotic hyperglycaemia is an endocrine emergency characterised by elevated blood glucose levels and high plasma osmolarity. While hypoglycaemia-induced seizures are usually generalised, hyperglycaemia-induced seizures are often focal and secondary to the presence of brain lesions. Moreover, in the few studies in which language disorders of epileptic origin have been reported as a clinical manifestation of non-ketotic hyperglycaemia, the disorders were usually not isolated but were followed by partial motor seizures. We describe a patient who presented with non-convulsive partial status epilepticus and whose only sign was a fluctuating language disorder induced by non-ketotic hyperglycaemia. There were no accompanying brain lesions and the patient responded optimally to diazepam. Neurophysiological EEG evaluation was fundamental for the diagnosis.

Effects of levetiracetam on generalized discharges monitored with ambulatory EEG in epileptic patients

PURPOSE Quantitative analysis of epileptiform discharges (EDs) before and after the initiation of an antiepileptic treatment is a useful tool to objectively documentate the efficacy of an antiepileptic drug (AED). Aim of this study was to evaluate the effect of levetiracetam (LEV) on EDs, monitored with ambulatory EEG (A/EEG), in a limited series of patients with generalized epilepsy. METHODS We performed 24h A/EEG recording in basal condition and at follow-up after LEV therapy in 21 adult epileptic patients. Eleven received LEV as monotherapy and 10 as add-on. For each patient we quantified total epileptic activity considering the following parameters: total number, total duration, maximal duration and median duration of EDs. Self-reported information on the effect of LEV on clinical seizures was also collected, to determine the electro-clinical correlation. RESULTS A high variability of the response to LEV was observed in the monotherapy group, without statistical differences for all the parameters investigated. A significant reduction of the total number of seizures (113.6 vs. 41.2; p=.01) was observed in patients in add-on therapy. The modifications of epileptiform EEG abnormalities did not necessarily correlate with the self-reported clinical impressions. DISCUSSION The quantification of EDs monitored by A/EEG provides a useful objective support for evaluating the neurophysiologic profile and the real efficacy of an antiepileptic treatment. In our patients LEV was able to significantly reduce the EDs only in add-on therapy. Further larger studies are necessary to clarify the effects of LEV on electro-clinical features of generalized epilepsy.

An observational electro-clinical study of status epilepticus: From management to outcome

Status epilepticus (SE) is a neurological emergency associated with a high morbidity and mortality. A prospective 3-year study was conducted in our hospital on 56 consecutive inpatients with SE. Demographic and clinical data were collected. EEG and clinical SE features were considered for the SE classification, both separately and together. The etiology of SE was determined. Patients were treated according to international standardized protocols of guidelines for the management of epilepsy. Response to treatment was evaluated clinically and electrophysiologically. Outcome at 30 days was considered as good, poor or death. Convulsive SE (CSE) was observed in 35 patients and non-convulsive SE (NCSE) in 21. Patients with CSE, in particular focal-CSE, were older than those with NCSE. As regards etiology, patients with SE secondary to cerebral lesions were the oldest, followed by patients with anoxic SE and those with toxic dysmetabolic SE. A first-line treatment was usually sufficient to control seizure activity in lesional and epileptic SE, while more aggressive treatment was necessary in all anoxic SE patients. Outcome was good in 35 patients, poor in 12, while 9 died. A prompt neurophysiological EEG evaluation, combined with the clinical evaluation, helps to make a rapid prognosis and take therapeutic management decisions. First-line treatments may be sufficient to control electro-clinical status in lesional and epileptic SE, while intensive care unit management, a more aggressive therapeutic approach and continuous EEG monitoring are recommended for refractory SE.