New onset refractory status epilepticus (NORSE)

Responsive neurostimulation as a therapy for epilepsy following new-onset refractory status epilepticus: Case series and review of the literature

OBJECTIVE

To report clinical outcomes of patients who presented with new-onset refractory status epilepticus (NORSE), developed drug-resistant epilepsy (DRE), and were treated with responsive neurostimulation (RNS).

METHODS

We performed a retrospective review of patients implanted with RNS at our institution and identified three who originally presented with NORSE. Through chart review, we retrieved objective and subjective information related to their presentation, workup, and outcomes including patient-reported seizure frequency. We reviewed electrocorticography (ECoG) data to estimate seizure burden at 3, 6, 12, and 24 months following RNS implantation. We performed a review of literature concerning neurostimulation in NORSE.

RESULTS

Use of RNS to treat DRE following NORSE was associated with reduced seizure burden and informed care by differentiating epileptic from non-epileptic events.

CONCLUSIONS

Our single-center experience of three cases suggests that RNS is a safe and potentially effective treatment for DRE following NORSE.

SIGNIFICANCE

This article reports outcomes of the largest case series of NORSE patients treated with RNS. Since patients with NORSE are at high risk of adverse neuropsychiatric and cognitive sequelae beyond seizures, a unique strength of RNS over other surgical options is the ability to distinguish ictal or peri-ictal from non-epileptic events.

Second-line immunotherapy in new onset refractory status epilepticus

Several pieces of evidence suggest immune dysregulation could trigger the onset and modulate sequelae of new onset refractory status epilepticus (NORSE), including its subtype with prior fever known as febrile infection-related epilepsy syndrome (FIRES). Consensus-driven recommendations have been established to guide the initiation of first- and second-line immunotherapies in these patients. Here, we review the literature to date on second-line immunotherapy for NORSE/FIRES, presenting results from 28 case reports and series describing the use of anakinra, tocilizumab, or intrathecal dexamethasone in 75 patients with NORSE. Among them, 52 patients were managed with anakinra, 21 with tocilizumab, and eight with intrathecal dexamethasone. Most had elevated serum or cerebrospinal fluid cytokine levels at treatment initiation. Treatments were predominantly initiated during the acute phase of the disease (92%) and resulted, within the first 2 weeks, in seizure control for up to 73% of patients with anakinra, 70% with tocilizumab, and 50% with intrathecal dexamethasone. Cytokine levels decreased after treatment for most patients. Anakinra and intrathecal dexamethasone were mainly initiated in children with FIRES, whereas tocilizumab was more frequently prescribed for adults, with or without a prior febrile infection. There was no clear correlation between the response to treatment and the time to initiate the treatment. Most patients experienced long-term disability and drug-resistant post-NORSE epilepsy. Initiation of second-line immunotherapies during status epilepticus (SE) had no clear effect on the emergence of post-NORSE epilepsy or long-term functional outcomes. In a small number of cases, the initiation of anakinra or tocilizumab several years after SE onset resulted in a reduction of seizure frequency for 67% of patients. These data highlight the potential utility of anakinra, tocilizumab, and intrathecal dexamethasone in patients with NORSE. There continues to be interest in the utilization of early cytokine measurements to guide treatment selection and response. Prospective studies are necessary to understand the role of early immunomodulation and its associations with epilepsy and functional outcomes.

Risk factors and a predictive model for the occurrence of adverse outcomes in patients with new-onset refractory status epilepsy

Objectives

To determine risk factors for the occurrence of adverse outcomes in patients with new-onset refractory status epilepsy (NORSE) and to construct a concomitant nomogram.

Methods

Seventy-six adult patients with NORSE who were admitted to the Department of Neurology, First Affiliated Hospital of Sun Yat-sen University between January 2016 and December 2022 were enrolled for the study. Participants were divided into two-those with good and poor functional outcomes-and their pertinent data was obtained from the hospital medical recording system. Univariate analysis was used to identify potential causes of poor outcomes in both groups and a multivariate logistic regression model was used to identify risk factors for the occurrence of poor outcomes. Using the R programming language RMS package, a nomogram was created to predict the occurrence of poor outcomes.

Results

The NORSE risk of adverse outcome nomogram model included four predictors, namely duration of mechanical ventilation (OR = 4.370, 95% CI 1.221-15.640, p = 0.023), antiviral therapy (OR = 0.045, 95% CI 0.005-0.399, p = 0.005), number of anesthetics (OR = 13.428, 95% CI 2.16-83.48, p = 0.005) and neutrophil count/lymphocyte count ratio (NLR) (OR = 5.248, 95% CI 1.509-18.252, p = 0.009). The nomogram had good consistency and discrimination in predicting risk and can thus assist clinical care providers to assess outcomes for NORSE patients. Through ordinary bootstrap analyses, the results of the original set prediction were confirmed as consistent with those of the test set.

Conclusion

The nomogram model of risk of adverse outcomes in NORSE adult patients developed in this study can facilitate clinicians to predict the risk of adverse outcomes in NORSE patients and make timely and reasonable interventions for patients at high risk of adverse outcomes.

Temperature Control in Acute Brain Injury: An Update

Temperature control in severe acute brain injury (SABI) is a key component of acute management. This manuscript delves into the complex role of temperature management in SABI, encompassing conditions like traumatic brain injury (TBI), acute ischemic stroke (AIS), intracerebral hemorrhage (ICH), aneurysmal subarachnoid hemorrhage (aSAH), and hypoxemic/ischemic brain injury following cardiac arrest. Fever is a common complication in SABI and is linked to worse neurological outcomes due to increased inflammatory responses and intracranial pressure (ICP). Temperature management, particularly hypothermic temperature control (HTC), appears to mitigate these adverse effects primarily by reducing cerebral metabolic demand and dampening inflammatory pathways. However, the effectiveness of HTC varies across different SABI conditions. In the context of post-cardiac arrest, the impact of HTC on neurological outcomes has shown inconsistent results. In cases of TBI, HTC seems promising for reducing ICP, but its influence on long-term outcomes remains uncertain. For AIS, clinical trials have yet to conclusively demonstrate the benefits of HTC, despite encouraging preclinical evidence. This variability in efficacy is also observed in ICH, aSAH, bacterial meningitis, and status epilepticus. In pediatric and neonatal populations, while HTC shows significant benefits in hypoxic-ischemic encephalopathy, its effectiveness in other brain injuries is mixed. Although the theoretical basis for employing temperature control, especially HTC, is strong, the clinical outcomes differ among various SABI subtypes. The current consensus indicates that fever prevention is beneficial across the board, but the application and effectiveness of HTC are more nuanced, underscoring the need for further research to establish optimal temperature management strategies. Here we provide an overview of the clinical evidence surrounding the use of temperature control in various types of SABI.

Ketamine in the treatment of refractory and super-refractory status epilepticus: Experience from two centres

PURPOSE

There is insufficient evidence on the management of refractory status epilepticus (RSE) and super-RSE (SRSE). Ketamine is a N-methyl-d-aspartate receptor antagonist in the treatment of these entities. Our objectives were to study the effectiveness and safety of ketamine in the treatment of adult patients with RSE and SRSE, to determine the factors that can influence the response to ketamine, and to explore its use in patients without mechanical ventilation.

METHODS

Adult patients who had received intravenous ketamine for the treatment of RSE or SRSE at Hospital Universitario Clínico San Carlos (Madrid, Spain) or Hospital Universitari Vall d'Hebron (Barcelona, Spain) from 2017 to 2023 were retrospectively analysed.

RESULTS

This study included 58 adult patients, mean (standard deviation) age 60.2 (15.7) years, of whom 41 (70.7 %) were male; 33 (56.9 %) patients responded to ketamine without recurrence, with a low rate of adverse effects (8.6 %). The presence of SRSE at the time of ketamine initiation (OR 0.287, p = 0.028) and the time elapsed between status epilepticus onset and ketamine administration (OR 0.991, p = 0.034) were associated with worse response to ketamine. Patients treated without mechanical ventilation had similar rates of response without recurrence (62.5% vs 56.9 %) and lower mortality (37.5% vs 53.5 %) compared to the overall group.

CONCLUSION

Ketamine is an effective drug with few adverse effects. Prompt administration should be considered in patients with RSE requiring anaesthesia, in patients with SRSE, and in patients with RSE who do not respond to standard antiseizure drugs and in whom mechanical ventilation is not advised.

Long-term outcome in new onset refractory status epilepticus: a retrospective study

BACKGROUND

New onset refractory status epilepticus (NORSE) is a neurologic emergency without an immediately identifiable cause. The complicated and long ICU stay of the patients can lead to perceiving a prolongation of therapies as futile. However, a recovery is possible even in severe cases. This retrospective study investigates ICU treatments, short- and long-term outcome and ethical decisions of a case series of patients with NORSE.

METHODS

Overall, 283 adults were admitted with status epilepticus (SE) to the Neurocritical Care Unit of the University Hospital Zurich, Switzerland, between 01.2010 and 12.2022. Of them, 25 had a NORSE. We collected demographic, clinical, therapeutic and outcome data. Descriptive statistics was performed.

RESULTS

Most patients were female (68%), previously healthy (Charlson comorbidity index 1 [0-4]) and relatively young (54 ± 17 years). 96% presented with super-refractory SE. Despite extensive workup, the majority (68%) of cases remained cryptogenic. Most patients had a long and complicated ICU stay. The in-hospital mortality was 36% (n = 9). The mortality at last available follow-up was 56% (n = 14) on average 30 months after ICU admission. The cause of in-hospital death for 89% (n = 8) of the patients was the withholding/withdrawing of therapies. Medical staff except for one patient triggered the decision. The end of life (EOL) decision was taken 29 [12-51] days after the ICU admission. Death occurred on day 6 [1-8.5] after the decision was taken. The functional outcome improved over time for 13/16 (81%) hospital survivors (median mRS at hospital discharge 4 [3.75-5] vs. median mRS at last available follow-up 2 [1.75-3], p < 0.001).

CONCLUSIONS

Our data suggest that the long-term outcome can still be favorable in NORSE survivors, despite a prolonged and complicated ICU stay. Clinicians should be careful in taking EOL decisions to avoid the risk of a self-fulfilling prophecy. Our results encourage clinicians to continue treatment even in initially refractory cases.

Severe, Refractory Seizures: New-Onset Refractory Status Epilepticus and Febrile Infection-Related Epilepsy Syndrome

NORSE (new-onset refractory status epilepticus) and FIRES (febrile infection-related epilepsy syndrome) represent presentations of new-onset status epilepticus without apparent underlying structural, metabolic, or toxic etiology. The cause of NORSE/FIRES remains cryptogenic in up to half of cases, and an abnormal response of the innate immune system has been implicated. Consensus guidelines recommend broad diagnostic investigation and empiric treatment with immunotherapy. NORSE/FIRES is associated with poor outcomes including cognitive impairment and epilepsy, but early recognition and treatment may be important for improving outcomes.

Febrile infection-related epilepsy syndrome in childhood: A clinical review and practical approach

Febrile infection-related epilepsy syndrome (FIRES) of unknown aetiology is an extremely rare but severe epilepsy syndrome. It is characterized by a nonspecific febrile infection a few days before the onset of super-refractory status epilepticus, followed by refractory epilepsy and high morbidity in previously healthy children and young adults. To date, FIRES is incurable and irreversible. The clinical course may depend more on time than on therapy, while the outcome may depend more on the clinical spectrum than on therapy. Based on a literature search, retrospective data analysis, and personal observations, this review aimed to explore the clinical spectrum and therapeutic options for FIRES to improve outcomes by optimized and more standardized diagnosis and therapy, including adapted immunotherapy and a less aggressive approach to manage seizures, as seizure-freeness is difficult to achieve and, therefore, not the primary goal for cryptogenic FIRES.

Lidocaine as a potential therapeutic option for super-refractory status epilepticus: A case report

New-onset refractory status epilepticus (NORSE) is a rare and devastating condition and the prognosis is often poor, with half to two-thirds of survivors experiencing drug-resistant epilepsy, residual cognitive impairment, or functional disability, and the mortality rate is 16% to 27% for adults. We describe a patient with cryptogenic NORSE and favorable recovery from drug-resistant super-refractory SE after the use of intravenous lidocaine. The patient experienced fever and presented with refractory generalized tonic-clonic seizures. The cause was not found by performing extensive examinations, including cell surface autoantibodies and rat brain immunohistochemistry evaluations. The refractory SE with unresponsiveness to multiple anti-epileptic and prolonged sedative medications, which are necessary for prolonged mechanical ventilation, were ameliorated by additive treatment with intravenous lidocaine initiating at 1 mg/kg/h and maintaining at 2 mg/kg/h for 40 days, which led to freedom from intravenous sedative medication and mechanical ventilation. The patient was able to return to school. Lidocaine may be an optional treatment for cryptogenic NORSE.

Multimodal Management of Febrile Infection-Related Epilepsy Syndrome in a 17-Year-Old Male

New-onset refractory status epilepticus (NORSE) is a clinical presentation, not a specific diagnosis, in which healthy people are suddenly struck by prolonged seizures that do not respond to at least two anti-seizure drugs and do not have a clear structural, toxic, or metabolic cause.Febrile infection-related epilepsy syndrome (FIRES) is considered a sub-category of NORSE. Our patient is a 17-year-old male admitted to the pediatric ward after a self-limited convulsive episode at home, noted to occur following five days of upper respiratory infection symptoms accompanied by fever. After multiple generalized tonic-clonic seizures necessitating treatment, he went into status epilepticus despite multiple antiepileptic drugs. The possibility of FIRES had been considered from the onset of refractory status epilepticus; as a result, an intensive multimodal treatment regimen was proactively implemented with some clinical improvement.

Long-term outcomes in refractory status epilepticus

INTRODUCTION

Refractory status epilepticus (RSE) is a diagnosis that can be made when tonic-clonic status epilepticus (SE) and focal SE cannot be stopped by at least two anti-seizure medications after 30 and 60 minutes, respectively, from the time of commencement. It could result in mortality, loss of functionality, neurological deficiency, and other serious short- and long-term effects.

AREAS COVERED

This narrative review covers original clinical studies of any design and case series investigating long-term outcomes of RSE recorded after at least a year from the SE onset.

EXPERT OPINION

The future of a patient with RSE rests mostly on the long-term effects of this severe pathological condition, which may be accompanied with systemic complications like hyperthermia, hyperkalemia, acidosis, and/or stress cardiomyopathy. Younger patients with less severe RSE of shorter duration, particularly of the convulsive kind, are reported to have better long-term outcomes. Previous studies on the factors influencing the long-term outcomes of RSE, however, did not link the outcomes to treatment options for the condition. Such circumstances currently prevent making any definitive recommendations on the treatment of RSE until future research with adequate statistical power is completed.

Neuromodulation in new-onset refractory status epilepticus

Background

New-onset refractory status epilepticus (NORSE) and its subset of febrile infection-related epilepsy syndrome (FIRES) are devastating clinical presentations with high rates of mortality and morbidity. The recently published consensus on the treatment of these conditions includes anesthetics, antiseizure drugs, antivirals, antibiotics, and immune therapies. Despite the internationally accepted treatment, the outcome remains poor for a significant percentage of patients.

Methods

We conducted a systematic review of the use of neuromodulation techniques in the treatment of the acute phase of NORSE/FIRES using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Results

Our search strategy brought up 74 articles of which 15 met our inclusion criteria. A total of 20 patients were treated with neuromodulation. Thirteen cases represented FIRES and in 17 cases the NORSE remained cryptogenic. Ten had electroconvulsive therapy (ECT), seven had vagal nerve stimulation (VNS), and four had deep brain stimulation (DBS); one patient had initially VNS and later DBS. Eight patients were female and nine were children. In 17 out of 20 patients, the status epilepticus was resolved after neuromodulation, while three patients died.

Conclusion

NORSE can have a catastrophic course and the first treatment goal should be the fastest possible termination of status epilepticus. The data presented are limited by the small number of published cases and the variability of neuromodulation protocols used. However, they show some potential clinical benefits of early neuromodulation therapy, suggesting that these techniques could be considered within the course of FIRES/NORSE.

Safe and effective implantation and use of vagal nerve stimulation in new-onset refractory status epilepticus in early pregnancy: a case report

Introduction

The management of new-onset refractory status epilepticus (NORSE) in pregnancy may be complicated by anti-seizure medication (ASM) polytherapy-associated teratogenicity. We aim to demonstrate the safety and efficacy of vagal nerve stimulation (VNS) in a pregnant patient presenting with NORSE.

Case description

A 30-year old female, at 5-weeks' gestation presented with drug-refractory myoclonic status epilepticus, responsive only to high levels of anesthetic agents. The severity of seizures did not allow extubation, and the patient remained ventilated and sedated. VNS was implanted 26 days after seizure onset. The immediate post-operative output was 0.25 mA, which was rapidly titrated up to 0.5 mA the next morning, and to 0.75 mA that afternoon. This was further increased to 1.0 mA on 3rd day post-operation, and to 1.25 mA 7 days post-op. Myoclonic jerks diminished significantly 7 days post-op, allowing extubation. Twenty days after VNS implantation, no myoclonic jerks were observed. There was also a notable neurological improvement including increased alertness and mobility, and ability to obey commands. Drug overdose was subsequently found to be the most likely etiology of her NORSE. An early pregnancy assessment 17 days after VNS implantation showed a normally sited pregnancy, normal fetal heart activity and crown-rump length. The patient remained seizure free, gained functional independence and delivered a premature but otherwise healthy baby at 33 weeks' gestation.

Conclusion

NORSE is challenging to manage, further compounded in pregnancy due to the teratogenicity of ASMs and ASM polytherapy. This is the first case-study to report the safe implantation and use of VNS during the first trimester of pregnancy for the management of NORSE.

A practical approach to in-hospital management of new-onset refractory status epilepticus/febrile infection related epilepsy syndrome

New-onset refractory status epilepticus (NORSE) is "a clinical presentation, not a specific diagnosis, in a patient without active epilepsy or other preexisting relevant neurological disorder, with new onset of refractory status epilepticus without a clear acute or active structural, toxic, or metabolic cause." Febrile infection related epilepsy syndrome (FIRES) is "a subcategory of NORSE that requires a prior febrile infection, with fever starting between 2 weeks and 24 h before the onset of refractory status epilepticus, with or without fever at the onset of status epilepticus." These apply to all ages. Extensive testing of blood and CSF for infectious, rheumatologic, and metabolic conditions, neuroimaging, EEG, autoimmune/paraneoplastic antibody evaluations, malignancy screen, genetic testing, and CSF metagenomics may reveal the etiology in some patients, while a significant proportion of patients' disease remains unexplained, known as NORSE of unknown etiology or cryptogenic NORSE. Seizures are refractory and usually super-refractory (i.e., persist despite 24 h of anesthesia), requiring a prolonged intensive care unit stay, often (but not always) with fair to poor outcomes. Management of seizures in the initial 24-48 h should be like any case of refractory status epilepticus. However, based on the published consensus recommendations, the first-line immunotherapy should begin within 72 h using steroids, intravenous immunoglobulins, or plasmapheresis. If there is no improvement, the ketogenic diet and second-line immunotherapy should start within seven days. Rituximab is recommended as the second-line treatment if there is a strong suggestion or proof of an antibody-mediated disease, while anakinra or tocilizumab are recommended for cryptogenic cases. Intensive motor and cognitive rehab are usually necessary after a prolonged hospital stay. Many patients will have pharmacoresistant epilepsy at discharge, and some may need continued immunologic treatments and an epilepsy surgery evaluation. Extensive research is in progress now via multinational consortia relating to the specific type(s) of inflammation involved, whether age and prior febrile illness affect this, and whether measuring and following serum and/or CSF cytokines can help determine the best treatment.

Drug-resistant seizures associated with hyperinflammatory monocytes in FIRES

OBJECTIVE

Therapeutic strategies for patients with febrile infection-related epilepsy syndrome (FIRES) are limited, ad hoc, and frequently ineffective. Based on evidence that inflammation drives pathogenesis in FIRES, we used ex vivo stimulation of peripheral blood mononuclear cells (PBMCs) to characterize the monocytic response profile before and after therapy in a child successfully treated with dexamethasone delivered intrathecally six times between hospital Day 23 and 40 at 0.25 mg/kg/dose.

METHODS

PBMCs were isolated from serial blood draws acquired during refractory status epilepticus (RSE) and following resolution associated with intrathecal dexamethasone therapy in a previously healthy 9-year-old male that presented with seizures following Streptococcal pharyngitis. Cells were stimulated with bacterial or viral ligands and cytokine release was measured and compared to responses in age-matched healthy control PBMCs. Levels of inflammatory factors in the blood and CSF were also measured and compared to pediatric healthy control ranges.

RESULTS

During RSE, serum levels of IL6, CXCL8, HMGB1, S100A8/A9, and CRP were significantly elevated. IL6 was elevated in CSF. Ex vivo stimulation of PBMCs collected during RSE revealed hyperinflammatory release of IL6 and CXCL8 in response to bacterial stimulation. Following intrathecal dexamethasone, RSE resolved, inflammatory levels normalized in serum and CSF, and the PBMC hyperinflammatory response renormalized.

SIGNIFICANCE

FIRES may be associated with a hyperinflammatory monocytic response to normally banal bacterial pathogens. This hyperinflammatory response may induce a profound neutrophil burden and the consequent release of factors that further exacerbate inflammation and drive neuroinflammation. Intrathecal dexamethasone may resolve RSE by resetting this inflammatory feedback loop.

Investigating the genetic contribution in febrile infection-related epilepsy syndrome and refractory status epilepticus

Introduction

Febrile infection-related epilepsy syndrome (FIRES) is a severe childhood epilepsy with refractory status epilepticus after a typically mild febrile infection. The etiology of FIRES is largely unknown, and outcomes in most individuals with FIRES are poor.

Methods

Here, we reviewed the current state-of-the art genetic testing strategies in individuals with FIRES. We performed a systematic computational analysis to identify individuals with FIRES and characterize the clinical landscape using the Electronic Medical Records (EMR). Among 25 individuals with a confirmed FIRES diagnosis over the last decade, we performed a comprehensive review of genetic testing and other diagnostic testing.

Results

Management included use of steroids and intravenous immunoglobulin (IVIG) in most individuals, with an increased use of immunomodulatory agents, including IVIG, plasma exchange (PLEX) and immunosuppressants such as cytokine inhibitors, and the ketogenic diet after 2014. Genetic testing was performed on a clinical basis in almost all individuals and was non-diagnostic in all patients. We compared FIRES with both status epilepticus (SE) and refractory status epilepticus (RSE) as a broader comparison cohort and identified genetic causes in 36% of patients with RSE. The difference in genetic signatures between FIRES and RSE suggest distinct underlying etiologies. In summary, despite the absence of any identifiable etiologies in FIRES, we performed an unbiased analysis of the clinical landscape, identifying a heterogeneous range of treatment strategies and characterized real-world clinical practice.

Discussion

FIRES remains one of the most enigmatic conditions in child neurology without any known etiologies to date despite significant efforts in the field, suggesting a clear need for further studies and novel diagnostic and treatment approaches.

New-Onset Refractory Status Epilepticus Due to a Novel MT-TF Variant

Objective

The gene MT-TF encodes the mitochondrial tRNA of phenylalanine (tRNAphe). Its variations have been described as extremely rare etiologies of a variety of mitochondrial phenotypes.

Methods

By means of whole-exome sequencing (WES), we detected a novel likely causative MT-TF variant (m.610T>C) in a family presenting with a combined movement disorder and epilepsy phenotype. The variant was present at 97% heteroplasmy in the peripheral blood and in a homoplasmic state in skin fibroblast-derived DNA.

Results

The inaugural manifestation in the index patient was new-onset refractory myoclonic status epilepticus (NORSE) at the age of 29 years. Her son presented later with developmental regression and myoclonic epilepsy. On the beginning of valproate because of ongoing myoclonic seizures, the index patient developed a generalized brain edema requiring bilateral craniotomy. In the course of the disease, epileptic manifestations abated, and both patients developed a severe movement disorder phenotype with prominent spastic-dystonic features. Both patients did not display any further sign of mitochondrial disease.

Discussion

Our report expands the clinicogenetic background of tRNAphedisease spectrum and highlights pitfalls in the diagnostics and management of mitochondrial epilepsy. The present findings advocate the introduction of rapid genetic testing in the diagnostic flow chart of NORSE in adults.

Is NORSE a meaningful clinical entity?

This article summarises the arguments for and against the proposition, debated at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures, that: 'NORSE is a meaningful clinical entity'. Here the two sides of the argument are briefly presented. This article is published as part of the special issue of Epilepsy & Behavior which are the proceedings of the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures.

Specific profiles of new-onset vs. non-inaugural status epilepticus: From diagnosis to 1-year outcome

While new-onset status epilepticus (NOSE) is a harbinger of chronic epilepsy, prospective medical data are sparse in terms of specifying whether the evolution of status epilepticus (SE) and seizure expression in NOSE resembles what occurs in patients who have already been diagnosed with epilepsy [non-inaugural SE (NISE)] in all aspects apart from its inaugural nature. The aim of this study was to compare the clinical, MRI, and EEG features that could distinguish NOSE from NISE. We conducted a prospective monocentric study in which all patients ≥18 years admitted for SE over a 6-month period were included. A total of 109 patients (63 NISE and 46 NOSE cases) were included. Despite similar modified Rankin scores before SE, several aspects of the clinical history distinguished NOSE from NISE patients. NOSE patients were older and frequently had neurological comorbidity and preexisting cognitive decline, but they had a similar prevalence of alcohol consumption to NISE patients. NOSE and NISE evolve in the same proportions as refractory SE (62.5% NOSE, 61% NISE) and share common features such as the same incidence (33% NOSE, 42% NISE, and p = 0.53) and volumes of peri-ictal abnormalities on MRI. However, in NOSE patients, we observed greater non-convulsive semiology (21.7% NOSE, 6% NISE, and p = 0.02), more periodic lateral discharges on EEG (p = 0.004), later diagnosis, and higher severity according to the STESS and EMSE scales (p < 0.0001). Mortality occurred in 32.6% of NOSE patients and 21% of NISE patients at 1 year (p = 0.19), but with different causes of death occurring at different time points: more early deaths directly linked to SE at 1 month occurred in the NOSE group, while there were more remote deaths linked to causal brain lesions in the NISE group at final follow-up. In survivors, 43.6% of the NOSE cases developed into epilepsy. Despite acute causal brain lesions, the novelty related to its inaugural nature is still too often associated with a delay in diagnosing SE and a poorer outcome, which justifies the need to more clearly specify the various types of SE to constantly raise awareness among clinicians. These results highlight the relevance of including novelty-related criteria, clinical history, and temporality of occurrence in the nosology of SE.

[Autoimmune encephalitis-Challenges and management in intensive medical care]

Despite relevant improvements in the diagnostics and treatment of autoimmune encephalitis (AE), severely affected patients still need treatment on the intensive care unit (ICU). Such complex disease states are sometimes difficult to bring under control and ICU complications have a negative influence on the outcome of treatment. A rapid diagnosis and timely initiation of immunotherapy are crucial to minimize ICU treatment and to avoid potentially severe complications. This article outlines the ICU treatment of autoimmune encephalitis and describes the most common challenges and complications of (neuro)intensive medical care and their management.

Seizure burden and neuropsychological outcomes of new-onset refractory status epilepticus: Systematic review

Background

Long-term sequelae of the new onset refractory status epilepticus (NORSE) include the development of epilepsy, cognitive deficits, and behavioral disturbances. The prevalence of these complications has been previously highlighted in case reports and case series: however, their full scope has not been comprehensively assessed.

Methods

We conducted a systematic review of the literature (PROSPERO ID CRD42022361142) regarding neurological and functional outcomes of NORSE at 30 days or longer following discharge from the hospital. A systematic review protocol was developed using guidance from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

Results

Of the 1,602 records for unique publications, 33 reports on adults and 52 reports on children met our inclusion criteria. They contained the description of 280 adults and 587 children of whom only 75.7 and 85% of patients, respectively had data on long-term follow-up. The mean age of adult and pediatric patients was 34.3 and 7.9 years, respectively; and the longest duration of follow up were 11 and 20 years, respectively. Seizure outcomes received major attention and were highlighted for 93.4 and 96.6% of the adult and pediatric NORSE patients, respectively. Seizures remained medically refractory in 41.1% of adults and 57.7% of children, while seizure freedom was achieved in only 26 and 23.3% of these patients, respectively. The long-term cognitive outcome data was provided for just 10.4% of the adult patients. In contrast, cognitive health data were supplied for 68.9% of the described children of whom 31.9% were moderately or severely disabled. Long-term functional outcomes assessed with various standardized scales were reported in 62.2 and 25.5% of the adults and children, respectively with majority of patients not being able to return to a pre-morbid level of functioning. New onset psychiatric disorders were reported in 3.3% of adults and 11.2% of children recovering from NORSE.

Conclusion

These findings concur with previous observations that the majority of adult and pediatric patients continue to experience recurrent seizures and suffer from refractory epilepsy. Moderate to severe cognitive disability, loss of functional independence, and psychiatric disorders represent a hallmark of chronic NORSE signifying the major public health importance of this disorder.

Perspective: Vagal nerve stimulation in the treatment of new-onset refractory status epilepticus

Introduction

Resistance to drug therapy is a major hurdle in new-onset refractory status epilepticus (NORSE) treatment and there is urgent need to develop new treatment approaches. Non-drug approaches such as neuromodulation offer significant benefits and should be investigated as new adjunct treatment modalities. An important unanswered question is whether desynchronizing networks by vagal nerve stimulation (VNS) may improve seizure control in NORSE patients.

Main text

We present a summary of published NORSE cases treated with VNS and our own data, discuss possible mechanisms of action, review VNS implantation timing, stimulation setting titration protocols and outcomes. Further, we propose avenues for future research.

Discussion

We advocate for consideration of VNS for NORSE both in early and late stages of the presentation and hypothesize a possible additional benefit from implantation in the acute phase of the disease. This should be pursued in the context of a clinical trial, harmonizing inclusion criteria, accuracy of documentation and treatment protocols. A study planned within our UK-wide NORSE-UK network will answer the question if VNS may confer benefits in aborting unremitting status epilepticus, modulate ictogenesis and reduce long-term chronic seizure burden.

A Pilot Study of High-Definition Transcranial Direct Current Stimulation in Refractory Status Epilepticus: The SURESTEP Trial

Refractory status epilepticus (RSE) is a life-threatening emergency with high mortality and poor functional outcomes in survivors. Treatment is typically limited to intravenous anesthetic infusions and multiple anti-seizure medications. While ongoing seizures can cause permanent neurological damage, medical therapies also pose severe and life-threatening side effects. We tested the feasibility of using high-definition transcranial direct current stimulation (hd-tDCS) in the treatment of RSE. We conducted 20-min hd-tDCS sessions at an outward field orientation, intensity of 2-mA, 4 + 1 channels, and customized for deployment over the electrographic maximum of epileptiform activity ("spikes") determined by real-time clinical EEG monitoring. There were no adverse events from 32 hd-tDCS sessions in 10 RSE patients. Over steady dosing states of infusions and medications in 29 included sessions, median spike rates/patient fell by 50% during hd-tDCS on both automated (p = 0.0069) and human (p = 0.0277) spike counting. Median spike rates for any given stimulation session also fell by 50% during hd-tDCS on automated spike counting (p = 0.0032). Immediately after hd-tDCS, median spike rates/patient remained down by 25% on human spike counting (p = 0.018). Compared to historical controls, hd-tDCS subjects were successfully discharged from the intensive care unit (ICU) 45.8% more often (p = 0.004). When controls were selected using propensity score matching, the discharge rate advantage improved to 55% (p = 0.002). Customized EEG electrode targeting of hd-tDCS is a safe and non-invasive method of hyperacutely reducing epileptiform activity in RSE. Compared to historical controls, there was evidence of a cumulative chronic clinical response with more hd-tDCS subjects discharged from ICU.

Inflammation as Treatment Target for Status Epilepticus

BACKGROUND

Status epilepticus (SE) is a serious neurological disease that manifests as prolonged seizures that last more than 5 minutes and between such episodes, patients do not regain consciousness. It can result in cognitive defects, brain damage, or even death. It is commonly known that one of the causes can be an inflammatory process, but here we will focus on inflammation as a result of new onset refractory status epilepticus and, related to this, new promising forms of SE treatment. Particular emphasis has been focused on new-onset refractory status epilepticus (NORSE).

METHODS

Based on public research databases, drugs with anti-inflammatory activity - commonly used in different spheres of medicine - have been reviewed as potentially treating status epilepticus.

RESULTS

There is seizable clinical research suggesting that drugs that decrease inflammatory processes might be effective in terminating status epilepticus.

CONCLUSION

There is growing evidence showing that adding anti-inflammatory drugs to basic antiepileptic treatment enhances the efficiency of the therapeutic process, with special potential in NORSE cases.

Early identification of NORSE and transfer to care setting with appropriate supports: A proposed algorithm

New-onset refractory status epilepticus (NORSE) is a clinical presentation where an individual develops refractory status epilepticus without active epilepsy, or related neurological conditions. A subset of these individuals has a preceding fever and would be diagnosed with febrile infection-related epilepsy syndrome (FIRES). The underlying etiology of this condition varies and includes autoimmune and viral encephalitides. These conditions require multiple specialized health care teams working collaboratively and specific resources for investigation of the underlying etiology and management to provide optimal patient care. In this paper, we provide: (1) recommendations upon early recognition of NORSE and FIRES, (2) guidance on the resources needed to optimally provide care, and (3) guidance on considerations to initiate transfer of patients to a more specialized medical center. Additional recommendations for resource-austere centers without the ability to transfer such patients are also discussed. These recommendations are only for adult patients with NORSE as pediatric patients may require additional special considerations.

The Increased Interleukin-6 Levels Can Be an Early Diagnostic Marker for New-Onset Refractory Status Epilepticus

New-onset refractory status epilepticus (NORSE) is a condition defined as the occurrence of refractory status epilepticus in patients without active epilepsy and no other acute causes of seizure. Although there is evidence that immune-mediated pathogenesis has a pivotal role in the epileptogenesis of NORSE, the diagnosis of NORSE is usually made on the clinical observation because there is no established biological marker suggesting the diagnosis of NORSE. We recently encountered a NORSE patient who was successfully treated with immunotherapy including tocilizumab, an anti-interleukin-6 (IL-6) receptor monoclonal antibody, and the markedly increased levels of serum and cerebrospinal fluid IL-6 were the only laboratory abnormality during the early treatment of the patient.

Seizures, Epilepsy, and NORSE Secondary to Autoimmune Encephalitis: A Practical Guide for Clinicians

The most recent International League Against Epilepsy (ILAE) classification has included "immune etiology" along with other well-known causes of epilepsy. This was possible thanks to the progress in detection of pathogenic neural antibodies (Abs) in a subset of patients, and resulted in an increased interest in identifying potentially treatable causes of otherwise refractory seizures. Most autoimmune encephalitides (AE) present with seizures, but only a minority of cases evolve to long-term epilepsy. The risk of epilepsy is higher for patients harboring Abs targeting intracellular antigens (T cell-mediated and mostly paraneoplastic, such as Hu, CV2/CRMP5, Ma2, GAD65 Abs), compared with patients with neuronal surface Abs (antibody-mediated and less frequently paraneoplastic, such as NMDAR, GABAbR, LGI1, CASPR2 Abs). To consider these aspects, conceptual definitions for two entities were provided: acute symptomatic seizures secondary to AE, and autoimmune-associated epilepsy, which reflect the different pathophysiology and prognoses. Through this manuscript, we provide an up-to-date review on the current state of knowledge concerning diagnosis and management of patients with Ab-mediated encephalitis and associated epilepsy. Special emphasis is placed on clinical aspects, such as brain magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) specificities, electroencephalographic (EEG) findings, cancer screening and suggestions for a rational therapeutic approach.

Early clinical features of new-onset refractory status epilepticus (NORSE) in adults

BACKGROUND

The aim of this study was to identify early clinical features of patients with new-onset refractory status epilepticus (NORSE) that could direct the treatment in the first days of hospitalisation.

METHODS

A retrospective cohort study of adult NORSE patients treated in the intensive care units of Helsinki University Hospital 2007-2018.

RESULTS

We found 19 adult NORSE patients who divided into three subgroups on the basis of their clinical features: viral encephalitis (n = 5, 26%), febrile infection-related epilepsy syndrome (FIRES) (n = 6, 32%) and afebrile NORSE (n = 8, 42%). FIRES and afebrile NORSE patients remained without confirmed etiology, but retrospectively two paraneoplastic and two neurodegenerative causes were suspected in the afebrile NORSE group. Viral encephalitis patients were median 64 years old (IQR 55-64), and four (80%) had prodromal fever and abnormal findings in the first brain imaging. FIRES patients were median 21 years old (IQR 19-24), all febrile and had normal brain imaging at onset. In the afebrile NORSE group, median age was 67 (IQR 59-71) and 50% had prodromal cognitive or psychiatric symptoms. FIRES patients differed from other NORSE patients by younger age (p = 0.001), respiratory prodromal symptoms (p = 0.004), normal brain MRI (p = 0.044) and lack of comorbidities (p = 0.011). They needed more antiseizure medications (p = 0.001) and anesthetics (p = 0.002), had a longer hospital stay (p = 0.017) and more complications (p < 0.001).

CONCLUSIONS

Among febrile NORSE patients, FIRES group was distinctive due to patients' young age, prodromal respiratory symptoms and normal first brain imaging. These features should be confirmed by subsequent studies as basis for selecting patients for early intensive immunotherapy.

Predicting the progression to super-refractory status epilepticus: A machine-learning study

AIM

Super-refractory status epilepticus (SRSE) is a status epilepticus (SE) that continues or recurs ≥24 h after the onset of anesthesia. We aimed to identify the predictors of progression to SRSE and the risk of 30-day mortality in patients with SRSE by using a machine learning technique.

METHODS

We reviewed consecutive SE episodes in patients aged ≥14 years at Baggiovara Civil Hospital (Modena, Italy) from 2013 to 2021. A classification and regression tree analysis was performed to develop a predictive model of progression to SRSE in SE patients. In SRSE patients, a multivariate analysis was conducted to identify predictors of 30-day mortality.

RESULTS

We included 705 patients, 16% of whom (113/705) progressed to SRSE. Acute symptomatic hypoxic etiology and age ≤ 68.5 years predicted the highest risk (87.1%) of progression to SRSE. Etiology other than acute symptomatic hypoxic and absence of NCSE predicted the lowest risk (3.6%) of progression to SRSE. The predictive model was accurate in 96.1% of patients not evolving to SRSE and in 48.7% of those evolving to SRSE. Among patients with SRSE, 46.9% (53/113) died within 30 days compared to 25.2% (149/592) of patients without SRSE (p < 0.001). Among patients with SRSE, older age was associated with increased 30-day mortality (odds ratio 1.075; 95% confidence interval: 1.031-1.112; p = 0.001).

CONCLUSIONS

Acute symptomatic hypoxic etiology and younger age are major predictors of progression to SRSE. In patients with SRSE, older age is associated with increased risk of short-term mortality.

FIRES—Pathophysiology, therapeutical approach, and outcome

Background

The acronym FIRES stands for febrile infection-related epileptic syndrome, which is a rare epileptic syndrome in the pediatric population. The initial presentation of FIRES is similar to febrile seizures (FS). Both start after a febrile episode; however, in FIRES the epileptic seizure evolves into a super refractory status epilepticus within days despite appropriate treatment. FIRES needs to be diagnosed early and treated by a multidisciplinary team to control the status epilepticus (SE) as fast as possible. Limiting the duration of the SE is paramount for the prevention of catastrophic sequelae such as severe neurologic disabilities or even death.

Objective/Conclusion

We describe possible pathophysiological mechanisms and summarize important clinical features of FIRES. The aim of this review is to raise awareness, foster early recognition and improve neurologic long-term outcomes. Moreover, we propose a diagnostic approach and list therapeutic options providing an algorithm.

Functional outcomes of patients with NORSE and FIRES treated with immunotherapy: A systematic review

OBJECTIVE

To determine the frequency of good functional outcomes in patients with NORSE and FIRES treated with immunotherapy.

METHODS

We performed a systematic search of the MedLine and EMBASE databases to gather studies including at least 5 patients with NORSE or FIRES and at least one patient treated with immunotherapy, and reporting functional outcomes. Good functional outcome was defined as a modified Rankin Scale (mRS) score ≤ 2 (or an equivalent measure) at the last available follow-up assessment. Only patients with known functional outcomes were included in the analysis.

RESULTS

We analyzed 16 studies including a total of 161 patients with NORSE. Six studies were carried out only with FIRES patients (n = 64). Of the 161 patients with NORSE, 141 (87.5%) received immunotherapy. Outcome data were available for 135, 56 of whom (41.4%) achieved good functional outcomes. Twenty-four of the 58 patients with FIRES treated with immunotherapy and for whom outcome data were available achieved good functional outcomes (41.3%). Mortality rates in patients with NORSE and FIRES treated with immunotherapy were 20/121 (16.5%) and 6/58 (10.3%), respectively. By type of immunotherapy, good functional outcomes were achieved in 36/89 patients receiving glucocorticoids (40.4%), 27/71 patients receiving IV immunoglobulins (38%), 11/37 patients treated with plasma exchange (29.7%), 5/17 patients receiving rituximab (29.4%), and 2/13 patients receiving cyclophosphamide (15.3%).

CONCLUSION

Despite the lack of randomised clinical trials, immunotherapy is frequently prescribed to patients with NORSE and FIRES. However, rates of functional dependence and mortality remain high in these patients. Second-line therapies achieved lower rates of good outcomes, probably because they were administered to patients with more severe, refractory disease.

International consensus recommendations for management of New Onset Refractory Status Epilepticus (NORSE) incl. Febrile Infection-Related Epilepsy Syndrome (FIRES): Statements and Supporting Evidence

OBJECTIVE

To develop consensus-based recommendations for the management of adult and paediatric patients with NORSE/FIRES based on best evidence and experience.

METHODS

The Delphi methodology was followed. A facilitator group of 9 experts was established, who defined the scope, users and suggestions for recommendations. Following a review of the current literature, recommendation statements concerning diagnosis, treatment and research directions were generated which were then voted on a scale of 1 (strongly disagree) to 9 (strongly agree) by a panel of 48 experts in the field. Consensus that a statement was appropriate was reached if the median score was greater or equal to 7, and inappropriate if the median score was less than or equal to 3. The analysis of evidence was mapped to the results of each statement included in the Delphi survey.

RESULTS

Overall, 85 recommendation statements achieved consensus. The recommendations are divided into five sections: 1) disease characteristics, 2) diagnostic testing and sampling, 3) acute treatment, 4) treatment in the post-acute phase, and 5) research, registries and future directions in NORSE/FIRES. The detailed results and discussion of all 85 statements are outlined herein. A corresponding summary of findings and practical flowsheets are presented in a companion article.

SIGNIFICANCE

This detailed analysis offers insight into the supporting evidence and the current gaps in the literature that are associated with expert consensus statements related to NORSE/FIRES. The recommendations generated by this consensus can be used as a guide for the diagnosis, evaluation, and management of patients with NORSE/FIRES, and for planning of future research.

International consensus recommendations for management of New Onset Refractory Status Epilepticus (NORSE) including Febrile Infection-Related Epilepsy Syndrome (FIRES): Summary and Clinical Tools

OBJECTIVE

To develop consensus-based recommendations for the management of adult and pediatric patients with NORSE/FIRES based on best available evidence and expert opinion.

METHODS

The Delphi methodology was followed. A facilitator group of 9 experts was established, who defined the scope, users and suggestions for recommendations. Following a review of the current literature, recommendation statements concerning diagnosis, treatment and research directions were generated which were then voted on a scale of 1 (strongly disagree) to 9 (strongly agree) by a panel of 48 experts in the field. Consensus that a statement was appropriate was reached if the median score was greater than or equal to 7, and inappropriate if the median score was less than or equal to 3.

RESULTS

Overall, 85 recommendation statements achieved consensus. The recommendations are divided into five sections: 1) disease characteristics, 2) diagnostic testing and sampling, 3) acute treatment, 4) treatment in the post-acute phase, and 5) research, registries and future directions in NORSE/FIRES. These are summarized in this article along with two practical clinical flowsheets: one for diagnosis and evaluation and one for acute treatment. A corresponding evidence-based analysis of all 85 recommendations alongside responses by the Delphi panel is presented in a companion article.

SIGNIFICANCE

The recommendations generated by this consensus can be used as a guide for the diagnosis, evaluation, and management of patients with NORSE/FIRES, and for planning of future research.

Immunity, Ion Channels and Epilepsy

Epilepsy is a common chronic neurological disorder in modern society. One of the major unmet challenges is that current antiseizure medications are basically not disease-modifying. Among the multifaceted etiologies of epilepsy, the role of the immune system has attracted considerable attention in recent years. It is known that both innate and adaptive immunity can be activated in response to insults to the central nervous system, leading to seizures. Moreover, the interaction between ion channels, which have a well-established role in epileptogenesis and epilepsy, and the immune system is complex and is being actively investigated. Some examples, including the interaction between ion channels and mTOR pathways, will be discussed in this paper. Furthermore, there has been substantial progress in our understanding of the pathophysiology of epilepsy associated with autoimmune encephalitis, and numerous neural-specific autoantibodies have been found and documented. Early recognition of immune-mediated epilepsy is important, especially in cases of pharmacoresistant epilepsy and in the presence of signs of autoimmune encephalitis, as early intervention with immunotherapy shows promise.

Child Neurology: Initial Presentation of PCDH19-Related Epilepsy with New Onset Refractory Status Epilepticus and Treatment with Anakinra

PCDH19-

related epilepsy is a developmental and epileptic encephalopathy typically presenting with epilepsy and varying degrees of intellectual disability. Seizures typically present in clusters of focal or generalized seizures, sometimes in the setting of fever. We present the case of a 7-month-old girl presenting with new-onset refractory status epilepticus (NORSE) that followed routine vaccine administration and ensuing cytokine storm. She was diagnosed with a pathogenic variant in PCDH19. The patient required five anti-seizure medications and pentobarbital-induced burst suppression for control of seizures. She was noted to have elevated serum cytokine levels (IL-2, IL-4, IL-10, IL-13, IL-17, IL-1 IL-1β, and IL-8) and CSF cytokine levels (IL-6 and IL-13). Anakinra was initiated and titrated based on serial cytokine levels, with doses ranging from 5-20 mg/kg/day resulting in reduction in cytokine levels and seizure reduction. By 14 months of age, she was able to be maintained on three active anti-seizure medications and with ketogenic diet for seizure control.

Long non-coding RNA Tug1 regulates inflammation in microglia and in status epilepticus rats through the NF-κB signaling pathway

Background

Inflammation plays an important role in the pathogenesis of status epilepticus (SE). The long non-coding RNA (lncRNA) taurine up-regulated gene1 (Tug1) plays a well-defined role in inflammatory diseases. However, the molecular mechanism of Tug1 in SE progression remains unknown. In present study, we investigated whether Tug1 is involved in microglial inflammation in SE rats.

Methods

The SE rat model was established via intraperitoneal injection of lithium chloride-pilocarpine. RNA-binding protein immunoprecipitation (RIP) and RIP sequencing were carried out in rat microglia (RM). Tug1 cloned into the adenovirus was overexpressed in the microglia. Knockdown of Tug1 was performed via siRNA transfection. The level of Tug1 and inflammatory factors IL-1β and TNF-α was examined by real-time polymerase chain reaction (RT-PCR) and western blotting. Protein levels of p65, p-p65, p-ΙκΒα and ΙκΒα were assessed by western blotting.

Results

The RIP-seq result showed 14 lncRNAs that bound to the NF-κB p65 protein in RM. The lncRNA Tug1 directly interacted with p65. The level of declined Tug1 was decreased in the hippocampus of SE rats. Overexpression of Tug1 reduced the LPS-induced inflammation and M1/M2 polarization of microglia, while knockdown of Tug1 aggravated the inflammatory response in microglia. Accordingly, the protein levels of p-p65/p65 and p-ΙκΒα/ΙκΒα were reduced in the Tug1-overexpression microglia and elevated in the Tug1-knockdown microglia.

Conclusions

These findings indicate that Tug1 modulates the inflammation in microglia through the NF-κB signal pathway, and the Tug1/P65 axis are like to play a significant role in the inflammatory processes, providing a valid target for the therapy of SE.

Neurological and cognitive outcomes after antibody-negative autoimmune encephalitis in children

AIM

To characterize the neurological and cognitive outcomes in children with antibody-negative autoimmune encephalitis (Ab-negative AE).

METHOD

A cohort of children presenting to our institution over a 10-year period with autoimmune encephalitis was identified by structured retrospective review of medical records. Clinical features at presentation and final follow-up were recorded. Neuropsychological testing was performed in a subset of patients. Outcomes after Ab-negative AE were compared with outcomes after N-methyl-D-aspartate receptor antibody encephalitis (NMDARE).

RESULTS

Forty-four patients (26 females, 18 males, median age 9y 2mo [interquartile range 4y 5mo-11y 8mo], 23 with NMDARE) with a diagnosis of autoimmune encephalitis were included. Postencephalitic epilepsy was more frequent after Ab-negative AE compared to NMDARE (61% vs 14%, p=0.002). Cognitive testing was performed in a subset of patients (n=21; Ab-negative AE=11, NMDARE=10). Full-scale IQ was lower after Ab-negative AE than NMDARE (mean IQ 75 vs 92, p=0.02), primarily because of reduced verbal comprehension index (80 vs 98, p=0.01) and working memory index (77 vs 95, p=0.09). The cognitive function most commonly impaired was executive function (80% [8/10] vs 22% [2/9]).

INTERPRETATION

Ab-negative AE was associated with poorer cognitive outcomes than NMDARE at 1-year follow-up. Further studies are required to evaluate if immunotherapy can be optimized to improve outcome.

[A case of febrile infection-related epilepsy syndrome requiring prolonged intensive care management: a trial of intravenous ketamine and intrathecal dexamethasone therapy]

A 16-year-old male was brought to the emergency room with fever and status epilepticus, and was diagnosed with febrile infection-related epilepsy syndrome (FIRES). Seizure control was not achieved and the patient developed multiple complications. Ketamine infusion therapy and intrathecal dexamethasone therapy were administered, in addition to other anti-seizure treatment and immunotherapy for super-refractory status epilepticus (SRSE). The patient was weaned from the ventilator on day 170 and was able to live at home, although he continued to experience monthly focal motor seizures and moderate motor impairment. This case suggests that more aggressive treatment might be an option in FIRES with prolonged SRSE.

New-onset refractory status epilepticus (NORSE) and febrile infection-related epilepsy syndrome (FIRES) of unknown aetiology: A comparison of the incomparable?

PURPOSE

The discussion is ongoing whether new-onset refractory status epilepticus (NORSE) in adults and febrile infection-related epilepsy syndrome (FIRES) in children are one syndrome if the aetiology is unknown. In this study we will compare an adult cohort with NORSE and a paediatric cohort with FIRES in order to determine if they are similar or different.

METHODS

We retrospectively compared 18 adults with NORSE versus 48 children with FIRES, both cohorts without identifiable cause despite extensive investigations. We analyzed demographic and clinical data using Mann-Whitney-U and χ²- tests.

RESULTS

NORSE affected more women (78% vs. 42%; P = 0.009) than in FIRES. Median acute hospital stay was longer in FIRES (35 days [interquartile range, IQR=36] vs. 20 days [IQR=19]; P<0.001). FIRES was treated more frequently with coma therapy (82% vs. 28%; P<0.001) and with a higher median number of antiseizure medicines (7 [IQR=5] vs. 4 [IQR=2]; P<0.001). Children with FIRES showed a higher cerebrospinal fluid (CSF) cell count (10 cells/μl; P = 0.002) but a lower CSF protein level than adults with NORSE (48 mg/dl; P = 0.028). Immunotherapy was administered more frequently in FIRES (73% vs. 22%; P<0.001) than in NORSE. Group differences in number of antiseizure medicines after hospital stay (P = 0.229) and in overall mortality (P = 0.327) were not significant.

CONCLUSION

In our explorative comparison, differences prevailed. NORSE and FIRES should be compared prospectively in age-matched cohorts.

New onset refractory status epilepticus: State of the art

NORSE (new onset refractory status epilepticus) has recently been defined as a clinical presentation, not a specific diagnosis, in a patient without active epilepsy or other preexisting relevant neurological disorder, with new onset of refractory status epilepticus without a clear acute or active structural, toxic or metabolic cause. It includes the concept of FIRES described in children with a similar condition but preceded by a 2-14-day febrile illness. NORSE constitutes the acute phase of an entity preceded by a prodromal phase which may be accompanied by numerous manifestations (febrile episode, behavioural changes, headache, …), and followed by a chronic phase marked by long-term neurological sequelae, cognitive impairment, epilepsy and functional disability. There are many causes of NORSE: autoimmune, infectious, genetic, toxic, … but in half of the cases, despite an exhaustive assessment, the cause remains undetermined. Paraneoplastic and non-paraneoplastic autoimmune encephalitis remains by far the leading cause of NORSE. For these reasons, immunotherapy should be considered rapidly in parallel with the treatment of the status epilepticus, including in cryptogenic NORSE. Good communication with the family is important because the management of the acute phase is long and difficult. Although mortality remains high (11-22%), and sequelae can be severe, the majority of survivors can have a good or fair outcome.

An ultra-long new onset refractory status epilepticus: Winning the battle but losing the war?

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Enduring epileptic seizures can lead to a wide array of neuroradiological and EEG alterations.

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Even in case of resolution, ultra-long NORSE has severe and disabling consequences.

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NORSE of unknown etiology is a therapeutic challenge.

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This case points out the need for disease modifying treatments in NORSE.

New onset refractory status epilepticus (NORSE), is a rare and challenging condition occurring in previously healthy people. The etiology often remains undiscovered and is frequently associated with an unfavorable outcome. We report the electroclinical and neuroradiological evolution of an ultra-long case of NORSE of unknown etiology.

A 38-year-old woman with a prodrome of fever, vomiting and diarrhea was admitted to our Intensive Care Unit for refractory convulsive status epilepticus (SE). Her past medical history was unremarkable. Extensive examinations were negative for potential viral, autoimmune and metabolic etiologies. Despite multiple therapeutical attempts with antiseizures medications, anesthetics and immunotherapy, seizures persisted. After nearly 6 months of enduring seizures, SE finally ceased and the patient gradually recovered to a minimum state of awareness. She was then able to communicate through one-word utterances and to understand simple tasks. At a three-years follow-up, she developed multifocal drug-resistant epilepsy, subcortical myoclonus and severe spastic quadraparesis, becoming completely dependent for activities of daily living.

To our knowledge, this represents one of the longest cases of NORSE with final status resolution at this time. However, ultra-long SE in this case led to severe and disabling neurological sequelae. Future studies focused on disease modifying treatments for refractory SE are needed.

Fever-Associated Seizures or Epilepsy: An Overview of Old and Recent Literature Acquisitions

In addition to central nervous system infections, seizures and fever may occur together in several neurological disorders. Formerly, based on the clinical features and prognostic evolution, the co-association of seizure and fever included classical febrile seizures (FS) divided into simple, complex, and prolonged FS (also called febrile status epilepticus). Later, this group of disorders has been progressively indicated, with a more inclusive term, as "fever-associated seizures or epilepsy" (FASE) that encompasses: (a) FS divided into simple, complex, and prolonged FS; (b) FS plus; (c) severe myoclonic epilepsy in infancy (Dravet syndrome); (d) genetic epilepsy with FS plus; and (e) febrile infection-related epilepsy syndrome (FIRES). Among the FASE disorders, simple FS, the most common and benign condition, is rarely associated with subsequent epileptic seizures. The correlation of FS with epilepsy and other neurological disorders is highly variable. The pathogenesis of FASE is unclear but immunological and genetic factors play a relevant role and the disorders belonging to the FASE group show to have an underlying common clinical, immunological, and genetic pathway. In this study, we have reviewed and analyzed the clinical data of each of the heterogeneous group of disorders belonging to FASE.

Cryptogenic new-onset refractory status epilepticus responded to anti-interleukin-6 treatment

OBJECTIVE

The aim of this case report was to describe a potential anti-interleukin (IL)-6 treatment for cryptogenic new-onset refractory status epilepticus (C-NORSE).

BACKGROUND

Although an underlying immune-mediated pathogenesis is considered present in some C-NORSE cases, many cases do not respond to classical immunotherapies.

CASE REPORT

We describe the case of a 46-year-old woman with C-NORSE who achieved cessation of long-lasting status epilepticus following administration of tocilizumab, an IL-6 receptor-blocking antibody, although the final outcome was poor.

CONCLUSIONS

Anti-IL-6 treatment may prove effective in stopping status epilepticus in some C-NORSE cases.

New-Onset Refractory Status Epilepticus (NORSE): The Queen Square Neuro-ICU experience

The introduction and widespread adoption of the term 'NORSE' - new-onset refractory status epilepticus - raises both fundamental conceptual and pragmatic questions. We studied a cohort of patients with 'NORSE' at the National Hospital for Neurology and Neurosurgery to investigate the clinical features, treatment responses, and outcomes with a focus on sub-group analysis. We identified 26 cases of 'NORSE'. There was no difference in prognosis between 'NORSE' and non-'NORSE' RSE, nor in any sub-analysis in the 'NORSE' cohort. We discuss the utility and validity of the term NORSE as a descriptor for a subgroup with RSE in whom the underlying etiologies are heterogeneous and pathophysiological mechanisms are unknown.