Pre- and Postictal Changes in the Innate Immune System: Cause or Effect?

INTRODUCTION: Recent studies have shown that inflammatory processes might play a role in epileptogenesis. Their role in ictogenesis is much less clear. The aim of this study was to investigate peri-ictal changes of the innate immune system by analyzing changes of immune cells, as well as pro- and anti-inflammatory cytokines. METHODS: Patients with active epilepsy admitted for video-EEG monitoring for presurgical evaluation were included. Blood was sampled every 20 min for 5 h on 3 consecutive days until a seizure occurred. After a seizure, additional samples were drawn immediately, as well as 1 and 24 h later. To analyze the different populations of peripheral blood mononuclear cells, all samples underwent FACS for CD3, CD4, CD8, CD56, CD14, CD16, and CD19. For cytokine analysis, we used a custom bead-based multiplex immunoassay for IFN-γ, IL-1ß, IL-1RA, IL-4, IL-6, IL-10, IL-12, IL-17, MCP-1, MIP-1α, and TNFα. RESULTS: Fourteen patients with focal seizures during the sampling period were included. Natural killer (NK) cells showed a negative correlation (ρ = -0.3362, p = 0.0195) before seizure onset and an immediate increase to 1.95-fold afterward. T helper (TH) and B cells decreased by 2 and 8%, respectively, in the immediate postictal interval. Nonclassical and intermediate monocytes decreased not until 1 day after the seizures, and cytotoxic T (TC) cells showed a long-lasting postictal increase by 4%. IL-10 and MCP-1 increased significantly after seizures, and IL-12 decreased in the postictal phase. DISCUSSION/CONCLUSION: Our study argues for a role of the innate immune system in the pre- and postictal phases. NK cells might be involved in preictal changes or be altered as an epiphenomenon in the immediate preictal interval.

Quantitative EEG After Subarachnoid Hemorrhage Predicts Long-Term Functional Outcome.

PURPOSE: Delayed cerebral ischemia is a major complication after subarachnoid hemorrhage. Our previous study showed that alpha power reduction in continuous quantitative EEG predicts delayed cerebral ischemia. In this prospective cohort, we aimed to determine the prognostic value of alpha power in quantitative EEG for the long-term outcome of patients with subarachnoid hemorrhage. METHODS: Adult patients with nontraumatic subarachnoid hemorrhage were included if admitted early enough for EEG to start within 72 hours after symptom onset. Continuous six-channel EEG was applied. Unselected EEG signals underwent automated artifact rejection, power spectral analysis, and detrending. Alpha power decline of ≥40% for ≥5 hours was defined as critical EEG event based on previous findings. Six-month outcome was obtained using the modified Rankin scale. RESULTS: Twenty-two patients were included (14 male; mean age, 59 years; Hunt and Hess grade I-IV; duration of EEG monitoring, median 14 days). Poor outcome (modified Rankin scale, 2-5) was noted in 11 of 16 patients (69%) with critical EEG events. All six patients (100%) without EEG events achieved an excellent outcome (modified Rankin scale 0, 1) (P = 0.0062; sensitivity 100%, specificity 54.5%). Vasospasm detected with transcranial Doppler/Duplex sonography appeared 1.5 days after EEG events and showed weaker association with outcome (P = 0.035; sensitivity 100%, specificity 45.5%). There was no significant association between EEG events and ischemic lesions on imaging (P = 0.1). Also, no association between ischemic lesions and outcome was seen (P = 0.64). CONCLUSIONS: Stable alpha power in quantitative EEG reflects successful therapy and predicts good functional outcome after subarachnoid hemorrhage. Critical alpha power reduction indicates an increased risk of poor functional outcome.

Long-term outcome after epilepsy surgery in older adults.

PURPOSE: The incidence of epilepsy in older adults is growing, as does the incidence of comorbidities. Therefore, when it comes to epilepsy surgery in medically intractable epilepsy, age is often seen as a limiting factor. To investigate the outcome after epilepsy surgery in a population of older adults, we compared the benefit for patients aged 50-59 years with those aged 60 years and older in respect of efficacy and safety. METHOD: Patients aged ≥50 years with medically intractable epilepsy who underwent epilepsy surgery from 1990 to 2013 were selected from the database of a German epilepsy center. All of them received a standardised and detailed presurgical diagnostic evaluation. Follow-up included at least four scheduled visits with EEG, MRI and neuropsychological testing. Outcome was assessed using the Engel outcome scale. RESULTS: 79 patients aged between 50 and 67 years were followed-up for a median of 4.7 years (2-16 years). 68% of patients were free of disabling seizures (Engel class I, ≥60 years: 75%) and 58% were seizure-free (Engel class IA, ≥60 years: 70%). 90% of our patients suffered from temporal lobe epilepsy (TLE), 9% from frontal lobe epilepsy (FLE) and one occipital lobe epilepsy (OLE). After surgery, 9% discontinued or tapered their medication. Permanent surgical complications occurred in 10% of cases and transient neurological deficits were seen in 11%. Older patients had a higher risk for postoperative hygroma (≥60 years 15%; <60 years 8%) and were more prone to postoperative memory deficits (≥60 years 45%), especially after resection of the dominant temporal lobe. Verbal and figural memory testing did not differ significantly between the groups. CONCLUSIONS: The results support the view that in selected older patients, epilepsy surgery shows equal or even higher success rates as compared to younger patients. However, patients of older age may be at greater risk for postoperative hygroma and memory deficits, especially after dominant temporal lobe resections.

Nonadherence to antiepileptic drugs in Germany: A retrospective, population-based study.

OBJECTIVE: To assess the effect of patient and drug characteristics on medication adherence in people with epilepsy (PWE) in a large cohort representative of the German population. METHODS: Information was obtained from the Disease Analyzer database that collects anonymous demographic and medical data from practice computer systems throughout Germany. From 2010 to 2013, adult PWE were retrospectively analyzed regarding demographic characteristics, comorbidities, and treatment with antiepileptic drugs (AED). Adherence was measured using the medication possession ratio (MPR). Individuals with an MPR <80% were classified as nonadherent. Multivariate regression models were applied to assess the association of different factors with adherence by calculating adjusted odds ratios (OR) with 95% confidence intervals. RESULTS: A total of 31,317 PWE were included. The mean MPR was 81.1% (SD 25.7%) with 64.7% of patients showing good adherence (MPR >80%). Patient-related factors associated with good adherence to AED treatment were West German residence (OR 1.23, p < 0.0001) and learning disability (OR 1.80, p < 0.0001). Adherence was higher in patients treated with new than old (OR 1.52, p < 0.0001) and branded than generic AED (OR 1.44, p < 0.0001). Among the most common AED, levetiracetam achieved best adherence (OR 2.85, p < 0.0001), valproate lowest. Two or more daily dosages reduced adherence (TID vs QD: OR 0.84, p = 0.005; BID vs QD: OR 0.86, p = 0.011). CONCLUSIONS: One third of PWE treated with AED in Germany showed poor adherence, which was related to demographic characteristics and drug properties. Administration of new, well-tolerated drugs in simple dosage regimens improved AED compliance.

Biceps electromyography in dialeptic and automotor seizures with and without secondary generalization.

OBJECTIVE: Localization of seizure onset during presurgical video-EEG monitoring is indispensable for successful epilepsy surgery. Sometimes analysis of ictal EEG and video fails to identify this zone. Therefore, this study explored the hypothesis that ictal EMG recordings contribute to the lateralization or localization of focal epilepsy. METHODS: All patients with automotor or dialeptic seizures with or without secondary generalization were prospectively included during presurgical video-EEG monitoring over a 5years study period. We analyzed characteristics of ictal biceps EMG and compared the results to EEG and video findings. RESULTS: 79 patients with 185 seizures were included (51.9% male; 73.5% automotor and 26.5% dialeptic seizures; 24.3% seizures secondarily generalized). Even in dialeptic seizures, muscle tone increased bilaterally within seconds after EEG seizure onset (66.7%) without clinical movements. Bilateral "spindle-shaped" EMG activity during the automotor phase predicted secondary generalization in 88.7%. Increase of muscle activity in the contralateral side of the body in the beginning of the secondarily generalized tonic-clonic phase was detected in 78.1% after automotor seizures whereas this phenomenon was less pronounced after dialeptic seizures (69.2%). 38.5% of dialeptic seizures evolved into generalized tonic-unilateral clonic seizures. CONCLUSION: Ictal EMG recordings provide lateralizing signs especially in secondarily generalized automotor seizures. In addition, the study suggested that secondary generalization in automotor seizures is determined early already during the automotor phase. Dialeptic seizures can evolve only unilaterally into a tonic-clonic seizure while the other side of the body remains tonic. SIGNIFICANCE: Ictal biceps EMG can provide further information regarding lateralization of epileptic seizures.

Endogenous endophthalmitis complicating Streptococcus equi subspecies zooepidemicus meningitis: a case report.

BACKGROUND: Streptococcus equi subspecies zooepidemicus (Streptococcus zooepidemicus) is a rare cause of meningitis in humans. Humans mainly get infected by contact with an animal source or by ingestion of unpasteurized dairy products. In rare cases, bacterial meningitis can be complicated by endogenous endophthalmitis which is frequently associated with a poor visual prognosis. CASE PRESENTATION: A 73 year old male Caucasian patient presented with clinical signs indicative of bacterial meningitis. Blood and cerebrospinal fluid cultures yielded beta-hemolytic, catalase-negative cocci. The strain was identified as Streptococcus zooepidemicus. The patient was likely infected by contact with a sick horse. Under antibiotic treatment, his general condition improved rapidly. Early after hospital admission, however, he began seeing a black spot in his left eye's central visual field. An ophthalmological examination revealed signs of endogenous endophthalmitis and so the patient underwent vitrectomy. Despite treatment, the visual acuity of his left eye remained severely impaired. He showed no further neurological deficits at hospital discharge. CONCLUSION: Meningitis caused by Streptococcus zooepidemicus is rare with only 27 previously published adult cases in the literature. Of note, this report constitutes the third description of endogenous endophthalmitis associated with Streptococcus zooepidemicus meningitis. Thus, endogenous endophthalmitis may represent a comparatively common complication of meningitis caused by this microorganism.

Chronic valproate or levetiracetam treatment does not influence cytokine levels in humans.

PURPOSE: There is growing evidence that complex interactions between seizures and the immune system shape the course of epilepsy. However, systematic analyses of the effects of antiepileptic drugs (AED) on the immune system in humans are rare. We performed a prospective study on the influence of the widely used AED valproate and levetiracetam on interictal immunological parameters. METHODS: 36 patients were prospectively included. 15 were started on valproate (5 female (33%), age 54±27 years, 12 (80%) on monotherapy), 21 on levetiracetam (10 female (48%), age 45±19 years, 17 (81%) on monotherapy). Before treatment and after 3 months, we performed a differential blood count and analyzed the distribution of CD3(+)CD4(+)-, CD3(+)CD8(+)- and CD4(+)CD25(+)-leukocyte subsets using flow cytometry. In addition, we determined the concentrations of IL-1ß, IL-6, TNF-α and MCP-1 in the peripheral blood using ELISAs. RESULTS: Valproate intake resulted in a significant decrease of the total white blood count (6.96±1.23/nl vs. 6.13±1.57/nl, p=0.026) and of absolute count and percentage of neutrophils (4.60±1.05/nl vs. 3.69±1.30/nl, p=0.01; 65.4±7.9% vs. 59.5±11.5%, p=0.01, respectively). The percentage of CD3(+)CD4(+)-lymphocytes dropped significantly (50.4±10.9% vs. 45.3±12.3%, p=0.002). Levetiracetam treatment resulted in a decrease of the percentage of CD4(+)CD25(+)-lymphocytes (26.1±8.0% vs. 21.5±9.2%, p=0.01) but did not significantly alter absolute counts. Neither valproate nor levetiracetam were associated with significant changes in cytokines. CONCLUSION: Valproate intake results in profound changes of white blood cell count and subset distribution. Cytokine levels were not influenced by valproate or levetiracetam.