Long-term follow-up of febrile infection-related epilepsy syndrome

Steroid-Responsive Involuntary Movements as a Remote Symptom of Febrile Infection-Related Epilepsy Syndrome

Febrile infection-related epilepsy syndrome (FIRES) is a rare epileptic encephalopathy that occurs in children or adolescents. To date, evidence for the management of the post-acute phase of FIRES is focused on drug-resistant epilepsy that continues from the acute phase. Information on involuntary movements, which are newly developed in the chronic phase, is limited. We report a 13-year-old boy, who had a history of FIRES at nine years of age and experienced worsening seizure control that was accompanied by unremitting involuntary　movements after two years of a fairly controlled period. The involuntary movements resulted in motor deterioration and forced him to be bedridden. Although no neuronal autoantibodies were detected, we hypothesized that the boy's neurological deterioration was triggered by an autoimmune response based on the elevation of serum anti-glutamic acid decarboxylase and serum anti-thyroid peroxidase antibodies and hypermetabolism of bilateral lenticular nuclei on 18-fluorodeoxyglucose positron emission tomography that resembled those reported in patients with other types of autoimmune encephalitis. Serial methylprednisolone pulse therapy and intravenous immunoglobulin therapy ameliorated involuntary movements and improved his activities of daily living. Late-onset involuntary movements, along with seizure exacerbation, may appear in the chronic phase of FIRES. Immunotherapy could be effective in treating these symptoms.

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.

The Beneficial Outcome of Subsequent Treatment with Anakinra during the Chronic Phase of Febrile Infection-Related Epilepsy Syndrome (FIRES): A Case Report

This case report presents the clinical course of an eight-year-old boy diagnosed with febrile infection-related epilepsy syndrome (FIRES) at the age of four. Following a febrile infection, the patient experienced his initial episode of serial generalized clonic seizures. The severity of his condition led to 11 hospital admissions, totaling 157 days of hospitalization. Anakinra was initially administered during the acute phase in 2019 but was discontinued after 29 days. In 2022, the patient experienced a chronic-phase exacerbation and underwent a second course of anakinra treatment, which demonstrated a positive effect on seizure activity. With a year of anakinra therapy, the patient exhibited significant improvement in both seizure frequency and severity. This report adds to the existing evidence supporting the potential use of anakinra in the treatment of FIRES, highlighting its effectiveness during the chronic phase and suggesting the potential benefits of subsequent administration.

Neuromodulation Techniques in Children with Super-Refractory Status Epilepticus

Status epilepticus (SE) is a life-threatening condition and medical emergency which can have lifelong consequences, including neuronal death and alteration of neuronal networks, resulting in long-term neurologic and cognitive deficits in children. When standard pharmacological treatment for SE is not successful in controlling seizures, the condition evolves to refractory SE (rSE) and finally to super-refractory SE (srSE) if it exceeds 24 h despite using anaesthetics. In this systematic review, we present literature data on the potential uses of clinical neuromodulation techniques for the management of srSE in children, including electroconvulsive therapy, vagus nerve stimulation, and deep brain stimulation. The evaluation of these techniques is limited by the small number of published paediatric cases (n = 25, one with two techniques) in peer-reviewed articles (n = 18). Although neuromodulation strategies have not been tested through randomised, prospective controlled clinical trials, this review presents the existing data and the potential benefits of neuromodulation therapy, suggesting that these techniques, when available, could be considered at earlier stages within the course of srSE intending to prevent long-term neurologic complications. Clinical trials aiming to establish whether early intervention can prevent long-term sequelae are necessary in order to establish the potential clinical value of neuromodulation techniques for the treatment of srSE in children.

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.

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.

Comparing late-onset epileptic spasm outcomes after corpus callosotomy and subsequent disconnection surgery between post-encephalitis/encephalopathy and non-encephalitis/encephalopathy

OBJECTIVE

We aimed to analyze the efficiency of corpus callosotomy (CC) and subsequent disconnection surgeries in patients with late-onset epileptic spasms (LOES) by comparing post-encephalitis/encephalopathy (PE) and non-encephalitis/encephalopathy (NE). We hypothesized these surgeries can control potential focal onset epileptic spasms (ES) in the NE group but not in the PE group.

METHODS

We retrospectively included 23 patients (12 with PE and 11 with NE) who initially underwent CC and subsequent disconnection surgeries (five NE). We compared the clinical courses, seizure types, MRI, video-EEG, epilepsy surgery, and seizure outcomes between the two groups.

RESULTS

The median age of LOES onset in the PE group was 2.8 (range 1.0-10.1 years) and 2.9 years (range 1.1-12.6) in the NE group. Bilateral MRI abnormalities were observed in both groups (PE, n = 12; NE, n = 3; P < 0.05). The PE group presented ES alone (n = 2), ES + focal seizures (FS) (n = 3), ES + generalized seizures (GS) (n = 3), and ES + FS + GS (n = 4) in addition to stimulus-induced startle seizures (SS) (n = 8) (mean 3.1 seizure types/patient). The NE group presented ES alone (n = 1), ES + FS (n = 2), and ES + FS + GS (n = 8) (mean 2.7 seizure types/patient). In the PE group, CC stopped ES (n = 1) and SS (n = 1) and achieved <50% SS (n = 3). In the NE group, CC achieved immediate ES-free status (n = 2) and < 50% ES (n = 1), and additional disconnection surgeries subsided all seizure types (n = 3) based on lateralized interictal/ictal EEG findings. LOES was significantly remitted by surgery in the NE group (6/11 [55%]) compared with the PE group (1/12 [8%]) (P < 0.05).

SIGNIFICANCE

LOES is a drug-resistant, focal/generalized/unknown onset ES. Lateralization of ES in NE could be achieved after CC and eliminated by further disconnection surgeries because of potential focal onset ES. LOES in PE had little benefit from CC for generalized onset ES. However, CC might reduce SS in patients in the PE group with multiple seizure types.

Review and standard operating procedures for collection of biospecimens and analysis of biomarkers in new onset refractory status epilepticus

New onset refractory status epilepticus (NORSE), including its subtype with a preceding febrile illness known as febrile infection-related epilepsy syndrome (FIRES), is one of the most severe forms of status epilepticus. The exact causes of NORSE are currently unknown, and there is so far no disease-specific therapy. Identifying the underlying pathophysiology and discovering specific biomarkers, whether immunologic, infectious, genetic, or other, may help physicians in the management of patients with NORSE. A broad spectrum of biomarkers has been proposed for status epilepticus patients, some of which were evaluated for patients with NORSE. Nonetheless, none has been validated, due to significant variabilities in study cohorts, collected biospecimens, applied analytical methods, and defined outcome endpoints, and to small sample sizes. The NORSE Institute established an open NORSE/FIRES biorepository for health-related data and biological samples allowing the collection of biospecimens worldwide, promoting multicenter research and sharing of data and specimens. Here, we suggest standard operating procedures for biospecimen collection and biobanking in this rare condition. We also propose criteria for the appropriate use of previously collected biospecimens. We predict that the widespread use of standardized procedures will reduce heterogeneity, facilitate the future identification of validated biomarkers for NORSE, and provide a better understanding of the pathophysiology and best clinical management for these patients.

Neuropathology of New-Onset Refractory Status Epilepticus (NORSE)

New-Onset Refractory Status Epilepticus (NORSE), including its subtype with a preceding febrile illness known as FIRES (Febrile Infection-Related Epilepsy Syndrome), is one of the most severe forms of status epilepticus. Despite an extensive workup (clinical evaluation, EEG, imaging, biological tests), the majority of NORSE cases remain unexplained (i.e., "cryptogenic NORSE"). Understanding the pathophysiological mechanisms underlying cryptogenic NORSE and the related long-term consequences is crucial to improve patient management and preventing secondary neuronal injury and drug-resistant post-NORSE epilepsy. Previously, neuropathological evaluations conducted on biopsies or autopsies have been found helpful for identifying the etiologies of some cases that were previously of unknown cause. Here, we summarize the findings of studies reporting neuropathology findings in patients with NORSE, including FIRES. We identified 64 cryptogenic cases and 66 neuropathology tissue samples, including 37 biopsies, 18 autopsies, and seven epilepsy surgeries (the type of tissue sample was not detailed for 4 cases). We describe the main neuropathology findings and place a particular emphasis on cases for which neuropathology findings helped establish a diagnosis or elucidate the pathophysiology of cryptogenic NORSE, or on described cases in which neuropathology findings supported the selection of specific treatments for patients with NORSE.

Cytokines in New-Onset Refractory Status Epilepticus Predict Outcomes

OBJECTIVE

The objective of this study was to investigate inflammation using cerebrospinal fluid (CSF) and serum cytokines/chemokines in patients with new-onset refractory status epilepticus (NORSE) to better understand the pathophysiology of NORSE and its consequences.

METHODS

Patients with NORSE (n = 61, including n = 51 cryptogenic), including its subtype with prior fever known as febrile infection-related epilepsy syndrome (FIRES), were compared with patients with other refractory status epilepticus (RSE; n = 37), and control patients without SE (n = 52). We measured 12 cytokines/chemokines in serum or CSF samples using multiplexed fluorescent bead-based immunoassay detection. Cytokine levels were compared between patients with and without SE, and between the 51 patients with cryptogenic NORSE (cNORSE) and the 47 patients with a known-etiology RSE (NORSE n = 10, other RSE n = 37), and correlated with outcomes.

RESULTS

A significant increase of IL-6, TNF-α, CXCL8/IL-8, CCL2, MIP-1α, and IL-12p70 pro-inflammatory cytokines/chemokines was observed in patients with SE compared with patients without SE, in serum and CSF. Serum innate immunity pro-inflammatory cytokines/chemokines (CXCL8, CCL2, and MIP-1α) were significantly higher in patients with cNORSE compared to non-cryptogenic RSE. Patients with NORSE with elevated innate immunity serum and CSF cytokine/chemokine levels had worse outcomes at discharge and at several months after the SE ended.

INTERPRETATION

We identified significant differences in innate immunity serum and CSF cytokine/chemokine profiles between patients with cNORSE and non-cryptogenic RSE. The elevation of innate immunity pro-inflammatory cytokines in patients with NORSE correlated with worse short- and long-term outcomes. These findings highlight the involvement of innate immunity-related inflammation, including peripherally, and possibly of neutrophil-related immunity in cNORSE pathogenesis and suggest the importance of utilizing specific anti-inflammatory interventions. ANN NEUROL 2023.

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.

Febrile infection-related Epilepsy Syndrome (FIRES): a severe encephalopathy with status epilepticus. Literature review and presentation of two new cases

FIRES is defined as a disorder that requires a prior febrile infection starting between 2 weeks and 24 h before the onset of the refractory status epilepticus with or without fever at the onset of status epilepticus. The patients, previously normal, present in the acute phase recurrent seizures and status epilepticus followed by a severe course with usually persistent seizures and residual cognitive impairment. Boundary with "new onset refractory status epilepticus (NORSE) has not clearly established. Pathogenetic hypothesis includes inflammatory or autoimmune mechanism with a possible genetic predisposition for an immune response dysfunction.Various types of treatment have been proposed for the treatment of the acute phase of the disorder to block the rapid seizures evolution to status epilepticus and to treat status epilepticus itself. Prognosis is usually severe both for control of the seizures and for cognitive involvement.FIRES is an uncommon but severe disorder which must be carefully considered in the differential diagnosis with other epileptic encephalopathy.

Long-term outcomes after NORSE: Treatment with vagus nerve stimulation

New-onset refractory status epilepticus (NORSE) is associated with high mortality, therapy-resistant epilepsy (TRE), and poor cognitive and functional outcomes. Some patients develop multifocal TRE, for whom surgery with a curative intention, is not an option. In these patients, vagus nerve stimulation (VNS) is performed as a palliative treatment. We report the long-term outcomes regarding seizure frequency, functional and cognitive outcome, and effectiveness of VNS in two patients with TRE as a consequence of NORSE. In the first patient with cryptogenic NORSE, VNS implantation occurred during the acute stage, probably contributing to the cessation of her status epilepticus. However, in the long-term follow-up, the patient persisted with daily multifocal seizures. In the second patient, VNS implantation was delayed to manage his epilepsy when the NORSE, ultimately due to autoimmune encephalitis, had resolved. During long-term follow-up, no reduction in seizure frequency was achieved. This evidence supporting the use of VNS in patients with TRE after NORSE warrants further investigation.

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.

Neuromodulation in Super-refractory Status Epilepticus

SUMMARY

Status epilepticus (SE) is a severe condition that needs immediate pharmacological treatment to tackle brain damage and related side effects. In approximately 20% of cases, the standard treatment for SE does not control seizures, and the condition evolves to refractory SE. If refractory status epilepticus lasts more than 24 hours despite the use of anesthetic treatment, the condition is redefined as super-refractory SE (srSE). sRSE is a destructive condition, potentially to cause severe brain damage. In this review, we discuss the clinical neuromodulation techniques for controlling srSE when conventional treatments have failed: electroconvulsive therapy, vagus nerve stimulation, transcranial magnetic stimulation, and deep brain stimulation. Data show that neuromodulation therapies can abort srSE in >80% of patients. However, no randomized, prospective, and controlled trials have been completed, and data are provided only by retrospective small case series and case reports with obvious inclination to publication bias. There is a need for further investigation into the use of neuromodulation techniques as an early treatment of srSE and to address whether an earlier intervention can prevent long-term complications.

Therapeutic plasma exchange in clinical pediatric neurology practice: Experience from a tertiary referral hospital

OBJECTIVE

This study aims to retrospectively evaluate the long-term efficacy, tolerability, and safety of therapeutic plasma exchange (TPE) in children with various neuroimmunological disorders.

METHODS

This analysis was a single-center, retrospective cohort study of pediatric patients with neuroimmunological events undergoing TPE procedures in a tertiary referral center.

RESULTS

There were 23 patients, 14 boys (60.9%), aged at diagnosis onset 8 months to 16.8 years. The main indications of TPE were Guillain-Barré syndrome (GBS, n = 8), autoimmune encephalitis (n = 5), febrile infection-related epilepsy syndrome (FIRES, n = 4), and acute disseminated encephalomyelitis (ADEM, n = 3). There was no life-threatening complication due to the TPE procedures. Eight (34.8%) of 23 patients experienced 13 (7%) complications in 186 TPE procedures, mostly electrolyte disturbances (n = 5). None of patients discontinued TPE due to complications. Two (8.7%) of 23 patients had marked improvement, 6 (26.1%) had moderate and 11 (47.8%) had mild improvement after TPE. The last follow-up visit revealed neurological sequelae in 12 (52.2%) patients. Therapeutic plasma exchange was found to be more effective on GBS, autoimmune encephalitis and myasthenia gravis, less effective on ADEM and FIRES. There was no correlation between improvement with TPE and clinical parameters, including age, sex, diagnosis, disease duration before TPE, presence of intubation, and length of stay in the intensive care unit and hospital.

CONCLUSION

Therapeutic plasma exchange was found to be effective and well-tolerated in children with various types of neuroimmunological disorder, with at least mild improvement in approximately 80% of the patients and no life-threatening complications.

Clinical presentation of new onset refractory status epilepticus in children (the pSERG cohort)

Objective

We aimed to characterize the clinical profile and outcomes of new onset refractory status epilepticus (NORSE) in children, and investigated the relationship between fever onset and status epilepticus (SE).

Methods

Patients with refractory SE (RSE) between June 1, 2011 and October 1, 2016 were prospectively enrolled in the pSERG (Pediatric Status Epilepticus Research Group) cohort. Cases meeting the definition of NORSE were classified as "NORSE of known etiology" or "NORSE of unknown etiology." Subgroup analysis of NORSE of unknown etiology was completed based on the presence and time of fever occurrence relative to RSE onset: fever at onset (≤24 h), previous fever (2 weeks–24 h), and without fever.

Results

Of 279 patients with RSE, 46 patients met the criteria for NORSE. The median age was 2.4 years, and 25 (54%) were female. Forty (87%) patients had NORSE of unknown etiology. Nineteen (48%) presented with fever at SE onset, 16 (40%) had a previous fever, and five (12%) had no fever. The patients with preceding fever had more prolonged SE and worse outcomes, and 25% recovered baseline neurological function. The patients with fever at onset were younger and had shorter SE episodes, and 89% recovered baseline function.

Significance

Among pediatric patients with RSE, 16% met diagnostic criteria for NORSE, including the subcategory of febrile infection‐related epilepsy syndrome (FIRES). Pediatric NORSE cases may also overlap with refractory febrile SE (FSE). FIRES occurs more frequently in older children, the course is usually prolonged, and outcomes are worse, as compared to refractory FSE. Fever occurring more than 24 h before the onset of seizures differentiates a subgroup of NORSE patients with distinctive clinical characteristics and worse outcomes.

Possible Role of High-Dose Barbiturates and Early Administration of Parenteral Ketogenic Diet for Reducing Development of Chronic Epilepsy in Febrile Infection-Related Epilepsy Syndrome: A Case Report

We describe the efficacy of high-dose barbiturates and early administration of a parenteral ketogenic diet (KD) as initial treatments for acute status epilepticus (SE) in an 8-year-old girl with febrile infection-related epilepsy syndrome (FIRES). The patient was admitted to our hospital with refractory focal SE. Abundant epileptic discharges over the left frontal region were observed on electroencephalogram (EEG). Treatment with continuous infusion of thiamylal for 4 hours, increased incrementally to 40 mg/kg/h, successfully ended the clinical SE, and induced a burst-suppression coma. The infusion rate was then gradually decreased to 4 mg/kg/h over the next 12 hours. Parenteral KD was administered from days 6 to 21 of illness. Continuous infusion of thiamylal was switched to midazolam on day 10 without causing seizures or EEG exacerbations. The patient has remained seizure free in the 15 months since hospital discharge. The effectiveness of KD for the treatment of FIRES has attracted attention amongst clinicians, but KD treatment may need to last for 2 to 4 days before it can stop SE, a time period that could cause irreversible brain damage. Considering the severity of SE in our patient and the dose of barbiturates needed to treat it, we consider this case to have had a good clinical outcome. The results suggest that rapid termination of seizure using high-dose barbiturates in conjunction with early administration of parenteral KD could reduce the development of chronic epilepsy in patients with FIRES.

New-onset refractory status epilepticus (NORSE)

New-onset refractory status epilepticus and its subcategory febrile infection-related epilepsy syndrome are rare devastating clinical presentations in those without pre-existing relevant history, often in schoolchildren or young adults, without a clear cause on initial investigations. A cause is later identified in up to half of adults, but in many fewer children. Patients often require protracted intensive care and are at significant risk of dying. Functional disability is common and subsequent chronic epilepsy is the norm, but some people do have good outcomes, even after prolonged status epilepticus. Patients need prompt investigations and treatment. Anaesthetic and antiseizure medications are supplemented by other treatment modalities, including the ketogenic diet. Despite limited evidence, it is appropriate to try to modify the presumed underlying pathogenesis with immune modulation early, with a more recent focus on using interleukin inhibitors. Optimising management will require concerted multicentre international efforts.

Proposal to optimize evaluation and treatment of Febrile infection-related epilepsy syndrome (FIRES): A Report from FIRES workshop

Febrile infection-related epilepsy syndrome (FIRES) is a rare catastrophic epileptic encephalopathy that presents suddenly in otherwise normal children and young adults causing significant neurological disability, chronic epilepsy, and high rates of mortality. To suggest a therapy protocol to improve outcome of FIRES, workshops were held in conjunction with American Epilepsy Society annual meeting between 2017 and 2019. An international group of pediatric epileptologists, pediatric neurointensivists, rheumatologists and basic scientists with interest and expertise in FIRES convened to propose an algorithm for a standardized approach to the diagnosis and treatment of FIRES. The broad differential for refractory status epilepticus (RSE) should include FIRES, to allow empiric therapies to be started early in the clinical course. FIRES should be considered in all previously healthy patients older than two years of age who present with explosive onset of seizures rapidly progressing to RSE, following a febrile illness in the preceding two weeks. Once FIRES is suspected, early administrations of ketogenic diet and anakinra (the IL-1 receptor antagonist that blocks biologic activity of IL-1β) are recommended.

Inflammation, ictogenesis, and epileptogenesis: An exploration through human disease

Epilepsy is seen historically as a disease of aberrant neuronal signaling manifesting as seizures. With the discovery of numerous auto-antibodies and the subsequent growth in understanding of autoimmune encephalitis, there has been an increasing emphasis on the contribution of the innate and adaptive immune system to ictogenesis and epileptogenesis. Pathogenic antibodies, complement activation, CD8+ cytotoxic T cells, and microglial activation are seen, to various degrees, in different seizure-associated neuroinflammatory and autoimmune conditions. These aberrant immune responses are thought to cause disruptions in neuronal signaling, generation of acute symptomatic seizures, and, in some cases, the development of long-term autoimmune epilepsy. Although early treatment with immunomodulatory therapies improves outcomes in autoimmune encephalitides and autoimmune epilepsies, patient identification and treatment selection are not always clear-cut. This review examines the role of the different components of the immune system in various forms of seizure disorders including autoimmune encephalitis, autoimmune epilepsy, Rasmussen encephalitis, febrile infection-related epilepsy syndrome (FIRES), and new-onset refractory status epilepticus (NORSE). In particular, the pathophysiology and unique cytokine profiles seen in these disorders and their links with diagnosis, prognosis, and treatment decision-making are discussed.

Therapeutic Options for Patients with Refractory Status Epilepticus in Palliative Settings or with a Limitation of Life-Sustaining Therapies: A Systematic Review

BACKGROUND

Refractory status epilepticus (RSE) represents a serious medical condition requiring early and targeted therapy. Given the increasing number of elderly or multimorbid patients with a limitation of life-sustaining therapy (LOT) or within a palliative care setting (PCS), guidelines-oriented therapy escalation options for RSE have to be omitted frequently.

OBJECTIVES

This systematic review sought to summarize the evidence for fourth-line antiseizure drugs (ASDs) and other minimally or non-invasive therapeutic options beyond guideline recommendations in patients with RSE to elaborate on possible treatment options for patients undergoing LOT or in a PCS.

METHODS

A systematic review of the literature in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, focusing on fourth-line ASDs or other minimally or non-invasive therapeutic options was performed in February and June 2020 using the MEDLINE, EMBASE and Cochrane databases. The search terminology was constructed using the name of the specific ASD or therapy option and the term 'status epilepticus' with the use of Boolean operators, e.g. "(brivaracetam) AND (status epilepticus)". The respective Medical Subject Headings (MeSH) and Emtree terms were used, if available.

RESULTS

There is currently no level 1, grade A evidence for the use of ASDs in RSE. The best evidence was found for the use of lacosamide and topiramate (level 3, grade C), followed by brivaracetam, perampanel (each level 4, grade D) and stiripentol, oxcarbazepine and zonisamide (each level 5, grade D). Regarding non-medicinal options, there is little evidence for the use of the ketogenic diet (level 4, grade D) and magnesium sulfate (level 5, grade D) in RSE. The broad use of immunomodulatory or immunosuppressive treatment options in the absence of a presumed autoimmune etiology cannot be recommended; however, if an autoimmune etiology is assumed, steroid pulse, intravenous immunoglobulins and plasma exchange/plasmapheresis should be considered (level 4, grade D). Even if several studies suggested that the use of neurosteroids (level 5, grade D) is beneficial in RSE, the current data situation indicates that there is formal evidence against it.

CONCLUSIONS

RSE in patients undergoing LOT or in a PCS represents a challenge for modern clinicians and epileptologists. The evidence for the use of ASDs in RSE beyond that in current guidelines is low, but several effective and well-tolerated options are available that should be considered in this patient population. More so than in any other population, advance care planning, advance directives, and medical ethical aspects have to be considered carefully before and during therapy.

New-onset refractory status epilepticus and febrile infection-related epilepsy syndrome

New-onset refractory status epilepticus (NORSE) and febrile infection-related epilepsy syndrome (FIRES) are relatively rare clinical presentations. They are characterized by de novo onset of refractory status epilepticus (RSE) without clearly identifiable acute or active cause (structural, toxic, or metabolic). We reviewed the literature using PubMed reports published between 2003 and 2019 and summarized the clinical, neurophysiological, imaging, and treatment findings. Focal motor seizures, which tend to evolve into status epilepticus, characterize the typical presentation. Disease course is biphasic: acute phase followed by chronic phase with refractory epilepsy and neurological impairment. Aetiology is unknown, but immune-inflammatory-mediated epileptic encephalopathy is suspected. Electroencephalograms show variety in discharges (sporadic or periodic, focal, generalized, or more frequently bilateral), sometimes with a multifocal pattern. About 70% of adult NORSE have abnormal magnetic resonance imaging (MRI); in paediatric series of FIRES, 61.2% of patients have a normal brain MRI at the beginning and only 18.5% during the chronic phase. No specific therapy for FIRES and NORSE currently exists; high doses of barbiturates and ketogenic diet can be used with some effectiveness. Recently, anakinra and tocilizumab, targeting interleukin pathways, have emerged as potential specific therapies. Mortality rate is around 12% in children and even higher in adults (16-27%).

Neurocritical care and target immunotherapy for febrile infection-related epilepsy syndrome

Febrile infection-related epilepsy syndrome (FIRES) is an intractable neurological disease characterized by an unexplained refractory status epilepticus triggered by febrile infection. A Consensus definition of FIRES was proposed in 2018, and its clinical features and prognosis are gradually being clarified. However, the development of effective treatments has been hindered as the etiology of this rare disease is as yet unelucidated. The basic approach to the management of FIRES, like other forms of epilepsy, is based on the control of seizures, however seizures are extremely intractable and require intravenous administration of large doses of anticonvulsants, mainly barbiturates. This treatment strategy produces various complications including respiratory depression and drug hypersensitivity syndrome, which make it more difficult to control seizures. Consequently, it is crucial to predict these events and to formulate a planned treatment strategy. As well, it is important to grow out of conventional treatment strategies that rely on only anticonvulsants, and alternative therapies are gradually being developed. One such example is the adoption of a ketogenic diet which may lead to reduced convulsions as well as improve intellectual prognosis. Further, overproduction of inflammatory cytokines in the central nervous system has been shown to be strongly related to the pathology of FIRES which has led to attempts at immunomodulation therapy including anti-cytokine therapy.

The ketogenic diet for paediatric patients with super-refractory status epilepticus in febrile infection-related epilepsy syndrome

Objective

To investigate the effect and safety of ketogenic diet (KD) for the treatment of paediatric patients with super-refractory status epilepticus (SRSE) in febrile infection-related epilepsy syndrome (FIRES).

Method

From January 1, 2015 to October 31, 2017, ten critically ill paediatric patients with SRSE in FIRES were included in this study and treated with KD. The treatment effects of KD were evaluated by using continuous encephalography (CEEG) and amplitude-integrated electro-encephalography (aEEG).

Results

All 10 patients fulfilled the diagnostic criteria of SRSE in FIRES and achieved ketosis within 24–72 h following the administration of KD. CEEG and aEEG were monitored for several weeks to assess the efficacy of KD on status epilepticus (SE). SE was contained in 8 patients within 2 to 19 days after initiation of KD, and KD was discontinued in the other 2 patients. One of the 10 patients demonstrated severe adverse effects.

Conclusion

KD may be an alternative and safe treatment option in critical paediatric patients with SRSE in FIRES.

Febrile Infection-Related Epilepsy Syndrome (FIRES): A Literature Review and Case Study

Febrile infection-related epilepsy syndrome (FIRES) is a catastrophic epileptic syndrome that strikes previously healthy children aged 3-15 years and has an unknown pathogenesis and few treatments. These children experience a nonspecific febrile illness that is followed by prolonged refractory status epilepticus. Although the etiology is unknown, FIRES has a biphasic presentation, with the acute phase beginning as seizure activity lasting 1-12 weeks, then followed by the chronic phase, which is characterized by refractory seizures that cluster every 2-4 weeks, and may continue to be multifocal and independent. Treatment of FIRES is difficult, typically unresponsive to antiepileptic drugs. Some children resolve temporarily with drug-induced burst suppression comas. Other therapies such as a ketogenic diet have limited benefit. The outcome varies with the length of the acute phase and is usually poor, with up to 30% of cases ending in death and 66-100% of survivors having intellectual disability. The authors present a case of a 6-year-old child presenting with FIRES and refractory status epilepticus, which continued despite multidrug therapy. The patient underwent immunomodulatory therapy with the eventual resolution of status, but she developed a chronic, moderately severe encephalopathy, including intractable epilepsy. This case highlights the challenges of FIRES and the potential of immunomodulatory therapies for children with this disorder.

The short-term and long-term outcome of febrile infection-related epilepsy syndrome in children

BACKGROUND

The febrile infection-related epilepsy syndrome (FIRES) is a catastrophic epileptic encephalopathy which developed the refractory status epilepticus following or during a nonspecific febrile illness. To analyze the short-term and long-term outcome of FIRES in the children, we retrospectively analyzed the related data.

METHODS

The motor outcome was evaluated by modified Rankin scale (mRS). Poor motor outcome was defined as a mRS score of 4 or higher at discharge. Significant motor decline was defined as the mRS difference more than 2 before hospital admission and at discharge.

RESULTS

We totally enrolled 25 patients for analysis. Four patients were expired during hospitalization, and one patient was lost to follow-up after discharge. Therefore, a total 20 patients were finally analyzed. The age of disease onset ranged from 1.6 to 17.2 years (mean: 9.6 ± 4.4 years). Newly acquired epilepsy and cognitive deficit occurred in 100% and 61%, respectively. The duration of the anesthetic agents ranged from 7 to 149 days (mean: 34.2 ± 36.1 days). The duration of anesthetic agent usage (p = 0.011), refractory epilepsy (p = 0.003), and the use of ketogenic diet (p = 0.004) were significantly associated with the poor long-term motor outcome, and the number of anesthetic agents tended to be associated with the poor long-term motor outcome (p = 0.050). In-hospital mortality was 16%. Significant functional decline at discharge occurred in 100%. However, there was improvement in long-term follow-up.

CONCLUSION

The outcome of FIRES is poor with significant mortality and morbidities. Refractory epilepsy with cognitive deficit in survived cases is common, but improvement is possible.

Vagus nerve stimulation in refractory and super-refractory status epilepticus - A systematic review

RATIONALE

Refractory status epilepticus (RSE) is the persistence of status epilepticus despite second-line treatment. Super-refractory SE (SRSE) is characterized by ongoing status despite 48 h of anaesthetic treatment. Due to the high case fatality in RSE of 16-39%, off label treatments without strong evidence of efficacy in RSE are often administered. In single case-reports and small case series totalling 28 patients, acute implantation of VNS in RSE was associated with 76% and 26% success rate in generalized and focal RSE respectively. We performed an updated systematic review of the literature on efficacy of VNS in RSE/SRSE by including all reported patients.

METHODS

We systematically searched EMBASE, CENTRAL, Opengre.eu, and ClinicalTrials.gov, and PubMed databases to identify studies reporting the use of VNS for RSE and/or SRSE. We also searched conference abstracts from AES and ILAE meetings.

RESULTS

45 patients were identified in total of which 38 were acute implantations of VNS in RSE/SRSE. Five cases had VNS implantation for epilepsia partialis continua, one for refractory electrical status epilepticus in sleep and one for acute encephalitis with refractory repetitive focal seizures. Acute VNS implantation was associated with cessation of RSE/SRSE in 74% (28/38) of acute cases. Cessation did not occur in 18% (7/38) of cases and four deaths were reported (11%); all of them due to the underlying disease and unlikely related to VNS implantation. Median duration of the RSE/SRSE episode pre and post VNS implantation was 18 days (range: 3-1680 days) and 8 days (range: 3-84 days) respectively. Positive outcomes occurred in 82% (31/38) of cases.

CONCLUSION

VNS can interrupt RSE and SRSE in 74% of patients; data originate from reported studies classified as level IV and the risk for reporting bias is high. Further prospective studies are warranted to investigate acute VNS in RSE and SRSE.

Ketogenic Diet as a Treatment for Super-Refractory Status Epilepticus in Febrile Infection-Related Epilepsy Syndrome

Background: Febrile infection-related epilepsy syndrome (FIRES) is a fatal epileptic encephalopathy associated with super-refractory status epilepticus (SRSE). Several treatment strategies have been proposed for this condition although the clinical outcomes are poor. Huge efforts from neurointensivists have been focused on identifying the characteristics of FIRES and treatment to reduce the mortality associated with this condition. However, the role of ketogenic diet (KD) in FIRES is not fully understood.

Methods: We performed a retrospective review of patients who met the diagnostic criteria of FIRES, SRSE, and were treated with KD between 2015 and 2018 at the Department of Pediatrics, Xiangya Hospital of Central South University. The following data were recorded: demographic features, clinical presentation, anticonvulsant treatment, timing and duration of KD and follow-up information. Electroencephalography recordings were reviewed and analyzed.

Results: Seven patients with FIRES were put on KD (5 via enteral route, and 2 via intravenous line) for SRSE in the PICU. The median age was 8. Four patients were male and 3 were female. Although patients underwent treatment with a median of 4 antiepileptic drugs and 2 anesthetic agents, the status epilepticus (SE) persisted for 7–31 days before KD initiation. After KD initiation, all patients achieved ketosis and SE disappeared within an average of 5 days (IQR 3.5), although there were minor side effects. In 6 patients, a unique pattern was identified in the EEG recording at the peak period. After initiation of KD, the number of seizures reduced, the duration of seizure shortened, the background recovered and sleep architecture normalized in the EEG recordings. The early initiation of KD (at the onset of SE) in the acute phase of patients decreased the mRS score in the subsequent period (p = 0.012, r = 0.866).

Conclusions: The characteristic EEG pattern in the acute phase promoted timely diagnosis of FIRES. Our data suggest that KD may be a safe and promising therapy for FIRES with SRSE, and that early initiation of KD produces a favorable prognosis. Therefore, KD should be applied earlier in the course of FIRES. Intravenous KD can be an effective alternative route of administration for patients who may not take KD enterally.

Functional deficiency in endogenous interleukin-1 receptor antagonist in patients with febrile infection-related epilepsy syndrome

OBJECTIVE

We recently reported successful treatment of a child with febrile infection-related epilepsy syndrome (FIRES), a subtype of new onset refractory status epilepticus, with the recombinant interleukin-1 (IL1) receptor antagonist (IL1RA) anakinra. On this basis, we tested whether endogenous IL1RA production or function is deficient in FIRES patients.

METHODS

Levels of IL1β and IL1RA were measured in serum and cerebrospinal fluid (CSF). The inhibitory activity of endogenous IL1RA was assessed using a cell-based reporter assay. IL1RN gene variants were identified by sequencing. Expression levels for the secreted and intracellular isoforms of IL1RA were measured in patient and control cells by real-time polymerase chain reaction.

RESULTS

Levels of endogenous IL1RA and IL1β were elevated in the serum and CSF of patients with FIRES (n = 7) relative to healthy controls (n = 10). Serum from FIRES patients drove IL1R signaling activity and potentiated IL1R signaling in response to exogenous IL1β in a cell-based reporter assay. Functional assessment of endogenous IL1RA activity in 3 FIRES patients revealed attenuated inhibition of IL1R signaling. Sequencing of IL1RN in our index patient revealed multiple variants. This was accompanied by reduced expression of intracellular but not secreted isoforms of IL1RA in the patient's peripheral blood mononuclear cells.

INTERPRETATION

Our findings suggest that FIRES is associated with reduced expression of intracellular IL1RA isoforms and a functional deficiency in IL1RA inhibitory activity. These observations may provide insight into disease pathogenesis for FIRES and other inflammatory seizure disorders and may provide a valuable biomarker for therapeutic decision-making. Ann Neurol 2019;85:526-537.

Long-term outcomes of status epilepticus: A critical assessment

We reviewed 37 studies reporting long-term outcomes after a status epilepticus (SE) episode in pediatric and adult populations. Study design, length of follow-up, outcome measures, domains investigated (mortality, SE recurrence, subsequent epilepsy, cognitive outcome, functional outcome, or quality of life), and predictors of long-term outcomes are summarized. Despite heterogeneity in the design of prior studies, overall risk of poor long-term outcome after SE is high in both children and adults. Etiology is the main determinant of outcome, and the effect of age or SE duration is often difficult to distinguish from the underlying cause. The effect of the treatment on long-term outcome after SE is still unknown.

New onset refractory status epilepticus (NORSE)

PURPOSE

To summarize the clinical features, suggested work-up, treatment and prognosis of new-onset refractory status epilepticus (NORSE), a condition recently defined as the occurrence of refractory status epilepticus (RSE) in a patient without active epilepsy, and without a clear acute or active structural, toxic or metabolic cause; and of the related syndrome of febrile infection-related epilepsy syndrome (FIRES), also recently defined as a subgroup of NORSE preceded by a febrile illness between 2 weeks and 24 h prior to the onset of RSE.

METHOD

Narrative review of the medical literature about NORSE and FIRES.

RESULTS

NORSE and FIRES mainly affect school-age children and young adults. A prodromal phase with flu-like symptoms precedes the SE onset in two third of NORSE cases, and by definition in all FIRES. Status epilepticus usually starts with repeated focal seizures with secondary bilateralization. Most cases evolve to super RSE (SRSE) and have unfavorable outcome, with short-term mortality of 12-27%, long-term disability and epilepsy. No specific imaging or laboratory abnormalities have been identified so far that allows an early diagnosis and half of adult cases remain of unknown etiology. A standardized diagnostic algorithm is provided and. Autoimmune encephalitis is the most frequent identified cause. In the absence of specific diagnosis, immunotherapy could be tried in addition to antiepileptic treatment.

CONCLUSIONS

This review presents the rare but devastating syndrome of NORSE, including the subcategory of FIRES. Early recognition with complete work-up is primordial to identify the underlying cause and promptly start appropriate treatment.

Pediatric refractory and super-refractory status epilepticus

PURPOSE

To summarize the available evidence related to pediatric refractory status epilepticus (RSE) and super-refractory status epilepticus (SRSE), with emphasis on epidemiology, etiologies, therapeutic approaches, and clinical outcomes.

METHODS

Narrative review of the medical literature using MEDLINE database.

RESULTS

RSE is defined as status epilepticus (SE) that fails to respond to adequately used first- and second-line antiepileptic drugs. SRSE occurs when SE persist for 24 h or more after administration of anesthesia, or recurs after its withdrawal. RSE and SRSE represent complex neurological emergencies associated with long-term neurological dysfunction and high mortality. Challenges in management arise as the underlying etiology is not always promptly recognized and therapeutic options become limited with prolonged seizures. Treatment decisions mainly rely on case series or experts' opinions. The comparative effectiveness of different treatment strategies has not been evaluated in large prospective series or randomized clinical trials. Continuous infusion of anesthetic agents is the most common treatment for RSE and SRSE, although many questions on optimal dosing and rate of administration remain unanswered. The use of non-pharmacological therapies is documented in case series or reports with low level of evidence. In addition to neurological complications resulting from prolonged seizures, children with RSE/SRSE often develop systemic complications associated with polypharmacy and prolonged hospital stay.

CONCLUSION

RSE and SRSE are neurological emergencies with limited therapeutic options. Multi-national collaborative efforts are desirable to evaluate the safety and efficacy of current RSE/SRSE therapies, and potentially impact patients' outcomes.

Febrile Infection-Related Epilepsy Syndrome (FIRES), a possible cause of super-refractory status epilepticus. Case report

Introducción: El estado epiléptico superrefractario (EES) es una patología con importante morbimortalidad que afecta el ambiente neuronal según el tipo y duración de las crisis.Presentación del caso: Se presenta el caso de un escolar con estado epiléptico superrefractario y crisis multifocales. Se descartaron causas metabólicas, estructurales, infecciosas, toxicológicas y autoinmunes y se utilizaron diferentes manejos anticonvulsivantes sin respuesta, lográndose control de las crisis 6 semanas después del ingreso a UCI. Se realizó un seguimiento de 12 años, periodo en el que el paciente presentó múltiples recaídas del estado epiléptico asociadas a la presencia de epilepsia refractaria con múltiples tipos de crisis, en su mayoría vegetativas; además se dio involución cognitiva.Discusión: Esta forma de estado epiléptico corresponde al síndrome de estado epiléptico facilitado por fiebre (FIRES), entidad de posible origen inmunológico conocida por ser refractaria al tratamiento agudo y al manejo cró- nico de la epilepsia y que se presenta como secuela. Su evolución no se ha descrito a largo plazo y por tanto no hay consenso sobre el manejo en la fase crónica.Conclusión: Es importante considerar esta etiología en estado epiléptico superrefractario para utilizar de forma temprana diferentes estrategias terapéuticas, como la dieta cetogénica, que permitan, por un lado, controlar su condición crítica y las crisis epilépticas a largo plazo y, por el otro, mejorar el pronóstico cognitivo, logrando así un impacto en la calidad de vida.

Roseolovirus-associated encephalitis in immunocompetent and immunocompromised individuals

The roseoloviruses, human herpesvirus (HHV)-6A, HHV-6B, and HHV-7, can cause severe encephalitis or encephalopathy. In immunocompetent children, primary HHV-6B infection is occasionally accompanied by diverse clinical forms of encephalitis. Roseolovirus coinfections with heterologous viruses and delayed primary HHV-7 infection in immunocompetent adults result in very severe neurological and generalized symptoms. Recovery from neurological sequelae is slow and sometimes incomplete. In immunocompromised patients with underlying hematological malignancies and transplantation, frequent single or simultaneous reactivation of roseoloviruses elicit severe, lethal organ dysfunctions, including damages in the limbic system, brain stem, and hippocampus. Most cases have been due to HHV-6B with HHV-6A accounting for 2-3%. The most severe manifestation of HHV-6B reactivation is post-transplantation limbic encephalitis. Seizures, cognitive problems, and abnormal EEG are common. Major risk factors for HHV-6B-associated encephalitis include unrelated cord blood cell transplantation and repeated hematopoietic stem cell transplantation. Rare genetic disorders, male gender, certain HLA constellation, and immune tolerance to replicating HHV-6 in persons carrying chromosomally integrated HHV-6 might also predispose an individual to roseolovirus-associated brain damage. At this time, little is known about the risk factors for HHV-7-associated encephalitis. Intrathecal glial cell destruction due to virus replication, overexpression of proinflammatory cytokines, and viral mimicry of chemokines all contribute to brain dysfunction. High virus load in the cerebrospinal fluid, hippocampal astrogliosis, and viral protein expression in HHV-6B-associated cases and multiple microscopic neuronal degeneration in HHV-7-associated cases are typical laboratory findings. Early empirical therapy with ganciclovir or foscarnet might save the life of a patient with roseolovirus-associated encephalitis.

Cannabidiol as a Potential Treatment for Febrile Infection-Related Epilepsy Syndrome (FIRES) in the Acute and Chronic Phases

Febrile infection-related epilepsy syndrome (FIRES) is a devastating epilepsy affecting normal children after a febrile illness. FIRES presents with an acute phase with super-refractory status epilepticus and all patients progress to a chronic phase with persistent refractory epilepsy. The typical outcome is severe encephalopathy or death. The authors present 7 children from 5 centers with FIRES who had not responded to antiepileptic drugs or other therapies who were given cannabadiol (Epidiolex, GW Pharma) on emergency or expanded investigational protocols in either the acute or chronic phase of illness. After starting cannabidiol, 6 of 7 patients' seizures improved in frequency and duration. One patient died due to multiorgan failure secondary to isoflourane. An average of 4 antiepileptic drugs were weaned. Currently 5 subjects are ambulatory, 1 walks with assistance, and 4 are verbal. While this is an open-label case series, the authors add cannabidiol as a possible treatment for FIRES.

Plasmapheresis for refractory status epilepticus Part II: A scoping systematic review of the pediatric literature

BACKGROUND

Our goal was to perform a scoping systematic review of the literature on the use of plasmapheresis or plasma exchange (PE) for refractory status epilepticus (RSE) in children.

METHODS

Articles from MEDLINE, BIOSIS, EMBASE, Global Health, Healthstar, Scopus, Cochrane Library, the International Clinical Trials Registry Platform, clinicaltrials.gov (inception to May 2016), reference lists of relevant articles, and gray literature were searched. The strength of evidence was adjudicated using both the Oxford and GRADE methodology by two independent reviewers.

RESULTS

Twenty-two original articles were identified, with 37 pediatric patients. The mean age of the patients was 8.3 years (age median: 8.5, range: 0.6 years-17 years). Seizure response to PE therapy occurred in 9 of the 37 patients (24.3%) included in the review, with 7 patients (18.9%) displaying resolution of seizures and 2 patients (5.4%) displaying a partial reduction in seizure volume. Twenty-eight of the 37 patients (75.7%) had no response to PE therapy. No adverse events were recorded.

CONCLUSIONS

Oxford level 4, GRADE D evidence exists to suggest little to no benefit of PE in pediatric RSE. Routine application of PE for pediatric RSE cannot be recommended at this time.

Generation of Febrile Seizures and Subsequent Epileptogenesis

Febrile seizures (FSs) occur commonly in children aged from 6 months to 5 years. Complex (repetitive or prolonged) FSs, but not simple FSs, can lead to permanent brain modification. Human infants and immature rodents that have experienced complex FSs have a high risk of subsequent temporal lobe epilepsy. However, the causes of FSs and the mechanisms underlying the subsequent epileptogenesis remain unknown. Here, we mainly focus on two major questions concerning FSs: how fever triggers seizures, and how epileptogenesis occurs after FSs. The risk factors responsible for the occurrence of FSs and the epileptogenesis after prolonged FSs are thoroughly summarized and discussed. An understanding of these factors can provide potential therapeutic targets for the prevention of FSs and also yield biomarkers for identifying patients at risk of epileptogenesis following FSs.

Etiological associations and outcome predictors of acute electroencephalography in childhood encephalitis

OBJECTIVES

To examine EEG features in a retrospective 13-year cohort of children with encephalitis.

METHODS

354 EEGs from 119 patients during their admission were rated blind using a proforma with demonstrated inter-rater reliability (mean k=0.78). Patients belonged to 12 etiological groups that could be grouped into infectious and infection-associated (n=47), immune-mediated (n=36) and unknown (n=33). EEG features were analyzed between groups and for risk of abnormal Liverpool Outcome Score and drug resistant epilepsy (DRE) at last follow up.

RESULTS

86% children had an abnormal first EEG and 89% had at least one abnormal EEG. 55% had an abnormal outcome, and 13% had DRE after median follow-up of 7.3years (2.0-15.8years). Reactive background on first EEGs (9/11, p=0.04) and extreme spindles (4/11, p<0.001) distinguished patients with anti-N-Methyl-d-Aspartate Receptor encephalitis. Non-reactive EEG background (48% first EEGs) predicted abnormal outcome (OR 3.8, p<0.001). A shifting focal seizure pattern, seen in FIRES (4/5), anti-voltage gated potassium channel (2/3), Mycoplasma (1/10), other viral (1/10) and other unknown (1/28) encephalitis, was most predictive of DRE after multivariable analysis (OR 11.9, p<0.001).

CONCLUSIONS

Non-reactive EEG background and the presence of shifting focal seizures resembling migrating partial seizures of infancy are predictors of abnormal outcome and DRE respectively in childhood encephalitis.

SIGNIFICANCE

EEG is a sensitive but non-discriminatory marker of childhood encephalitis. We highlight the EEG features that predict abnormal outcome and DRE.

Hippocampal Changes in Febrile Infection-Related Epilepsy Syndrome (FIRES)

Background

Febrile seizures are the most common seizure disorder in childhood, associated with a significant rise in body temperature. However, post-infectious refractory afebrile form of seizures in previously healthy children is being increasingly recognized in around the world, which evolves into a chronic refractory form of epilepsy. The term ‘Febrile infection-related epilepsy syndrome’ (FIRES) has been proposed for these conditions and represents a refractory severe post-infectious epileptic condition in previously normal children.

Case Report

We report the initial and follow-up MR imaging findings in a 5year-old with refractory epilepsy post-febrile seizures.

Conclusions

In summary, acute post-infectious seizures are increasingly being recognized across the globe with the newly coined term ‘Febrile infection-related epilepsy syndrome’(FIRES) for this group of immune-mediated epileptic encephalopathy in previously healthy children. This has three phases: episode of simple febrile infection, followed by acute refractory seizures and lastly the chronic phase of neuropsychological impairments and seizures.