Rapid loading of intravenous lacosamide: efficacy and practicability during presurgical video-EEG monitoring.

PURPOSE: This study investigates immediate efficacy and safety of intravenous application of de novo lacosamide (LCM) as add-on therapy in patients with pharmacoresistant focal epilepsy. METHODS: During presurgical video-electroencephalography (EEG) monitoring, 17 adult inpatients received LCM infusion (200 mg every 12 h for 2-3 days) followed by oral formulation with the same regimen. Before and after intravenous application of LCM, seizures and interictal epileptiform discharges (IEDs) recorded with continuous video-EEG monitoring were analyzed, and an assessment of adverse events (AEs) was performed daily. To evaluate the midterm tolerability and efficacy, follow-up visits were conducted 1 and 3 months after discharge from hospital. KEY FINDINGS: In the acute phase, intravenous initiation of LCM was well tolerated with few mild or moderate AEs (3 of 17, 17.6%). A significant reduction of seizure frequency in the treatment phase as compared to mean seizure frequency in the 2-day baseline phase was achieved (p < 0.05 for the first treatment day, and p < 0.005 for the second treatment day). On the first treatment day, 61.5% of the patients were seizure free, and 84.6% on the second treatment day. IED reduction after intravenous application of LCM was not significant. After 1 month, the 50% responder rate was 46.6% and after the 3-month period, 42.8%. SIGNIFICANCE: Our data suggest that rapid intravenous initiation of de novo LCM is safe and may protect against seizures in a rapid and midterm time window.

Spinal cord atrophy in triple A syndrome associated with a novel compound heterozygous mutation.

A 38-year-old male patient was admitted with slowly progressive spastic gait disturbance. Imaging revealed general spinal cord atrophy. Because of adrenal insufficiency, alacrima and achalasia, triple A syndrome was suspected. This is a case report of a triple A syndrome patient with a predominance of neurological features and a new heterozygous compound mutation in triple A syndrome gene.

Functional and morphological changes in the dentate gyrus after experimental status epilepticus.

Status epilepticus may cause long-term functional and structural consequences possibly resulting in brain dysfunctions such as chronic epilepsy. In epileptogenesis, the dentate gyrus plays a key role in regulating the excitability of highly vulnerable and potentially epileptogenic downstream structures in the hippocampus proper. One, four and eight weeks after electrically induced status epilepticus, excitability and neuronal degeneration in the rat dentate gyrus were examined with intracerebral electrodes and Fluoro Jade (FJ) staining, respectively. Half of the animals had developed chronic epilepsy by 8 weeks after status epilepticus. Sham-operated controls did not exhibit seizures, and the excitatory parameters remained unchanged. Compared to controls, 8 weeks after status epilepticus the population spike latency in the dentate gyrus was significantly reduced (p<0.05) and substantial neuronal degeneration was seen (p<0.05). In summary, status epilepticus results in functional and morphological alterations in the dentate gyrus likely contributing to epileptogenesis.

Circadian dentate gyrus excitability in a rat model of temporal lobe epilepsy.

In human mesial temporal lobe epilepsy (mTLE), seizure occurrence peaks in the late afternoon and early evening. This temporal binding of seizures has been replicated in animal models of mTLE following electrically-induced status epilepticus (SE). We hypothesized that in chronic epilepsy, alterations of circadian excitatory and inhibitory functions of the dentate gyrus (DG), which is believed to regulate the generation of limbic seizures, pathophysiologically contribute to the temporal binding of ictogenesis. We performed electrophysiological single and paired pulse measurements hourly over 24h in the DG of epileptic rats (n=8) 8 weeks after electrically induced SE. Results were compared to individual data obtained before induction of SE and to those of control animals (n=3). Pre and post SE data were analyzed in two distinct phases of the day, i.e. a high-seizure phase between 2p.m. and 10p.m. and a low-seizure phase between 10p.m. and 2p.m. In chronic epileptic animals, latency of evoked potentials was significantly reduced in the high-seizure phase (p=0.027) but not in the low-seizure phase. Compared to baseline values, paired pulse inhibition was significantly increased during the low-seizure phase (interpulse interval (IPI) 25ms, p=0.003; IPI 30ms; p<0.001) but not in the high-seizure phase. Similarly, when compared to controls, inhibition at IPI 20ms was diminished only in the high-seizure phase (p=0.027). Thus, in chronic epileptic animals, DG excitability is increased in the afternoon and early evening possibly contributing to the time of day-dependency of spontaneous seizures in this model system of mTLE. Alterations of circadian DG excitability in epileptic animals may be influenced by changes in hypothalamus-regulated superordinate functions such as excretion of endocrine hormones but further studies are needed.

Limbic self-sustaining status epilepticus in rats is not associated with hyperthermia.

PURPOSE: To evaluate the impact of limbic status epilepticus on temperature. METHODS: The perforant path in freely moving rats was stimulated electrically for 120 min to induce self-sustaining status epilepticus (SSSE). For 150 min after the end of stimulation, epidural temperature and electrographic and clinical seizure activity were assessed in animals with limbic and motor SSSE, as well as in animals without development of SE. RESULTS: Temperature in all animals with SSSE was elevated by 1.5+/-0.8 degrees C after the end of stimulation compared with baseline values (p<0.01). In animals with pure limbic SE, temperature decreased continuously to baseline values over the 150-min period of observation. In contrast, in animals with motor SSSE, temperature remained elevated during continuing epileptic activity and was still significantly higher 150 min after the end of stimulation compared with baseline (p<0.01). In animals that did not develop SSSE, temperature was not changed after the end of electrical stimulation and in the 150 min thereafter compared with baseline values. CONCLUSIONS: The results indicate that hyperthermia as seen in SE is the consequence of motor convulsions and not of epileptic activity itself, as seen in limbic SSSE.

Furosemide terminates limbic status epilepticus in freely moving rats.

PURPOSE: To evaluate the anticonvulsant properties of furosemide and to determine sedative side effects compared with pentobarbital and diuretic side effects compared with saline-treated controls in an experimental model of limbic status epilepticus. METHODS: Self-sustaining status epilepticus was induced in rats by continuous electrical stimulation of the perforant path. Five minutes after the end of the stimulation, animals were given 100 mg/kg furosemide, 30 mg/kg pentobarbital, or an equal amount of saline, intraperitoneally. After administration of the substance, animals were monitored clinically and electrographically for 3 h regarding status epilepticus, level of sedation, and diuresis. RESULTS: In seven of 10 animals, furosemide terminated status epilepticus after 68 +/- 26 min, whereas pentobarbital was successful in all animals after 5 +/- 0.8 min. In contrast to pentobarbital, sedation did not occur with furosemide. Weight loss after furosemide was 10.2 +/- 1.7% compared with 6.5 +/- 1.1% in animals given saline (p < 0.001). CONCLUSIONS: The results suggest that furosemide may serve as an alternative or additional agent for refractory complex partial status epilepticus in patients in whom common anesthetics are not justifiable.