New-Onset Status Epilepticus in Pediatric Patients: Causes, Characteristics, and Outcomes

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.

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

PURPOSE OF REVIEW

The concept and understanding of new-onset refractory status epilepticus (NORSE), and its subtype with prior fever known as febrile infection-related epilepsy syndrome (FIRES) have evolved in the recent past. This review aims to summarize the recent developments in the pathophysiology, diagnosis and management of these challenging conditions.

RECENT FINDINGS

NORSE and FIRES can have many different causes. Although the list of possible causes is still growing, they mostly fall in the categories of autoimmune encephalitis and genetic disorders. However, despite extensive investigations, most cases of NORSE and FIRES remain cryptogenic. Recent studies have pointed towards the key role of autoinflammation as a unifying pathophysiological mechanism in these cases. These findings also support the use of immunomodulatory treatment in this setting. Consensus recommendations on the management of NORSE and FIRES have recently been published.

SUMMARY

NORSE and FIRES remain challenging conditions to diagnose and treat. Recent findings from clinical and basic research and new recommendations, reviewed in this article, contribute to an emerging framework for management and future research.

Clinical Features and Management of Status Epilepticus in the Pediatric Intensive Care Unit

OBJECTIVES

Status epilepticus (SE) is associated with significant morbidity and mortality in children. SE in the pediatric intensive care unit (PICU) are not well characterized. The aim of this study is to retrospectively investigate the clinical features and treatment of seizures in children admitted to the PICU of our hospital.

METHODS

We retrospectively examined the clinical characteristics of patients aged between 1 month and 18 years who were admitted to our hospital with SE or who were diagnosed with SE after hospitalization and were followed up with continuous electroencephalographic monitoring between January 2015 and December 2019.

RESULTS

A total of 88 patients with SE, 50 (56.8%) boys and 38 (43.2%) girls, were included. The median age was 24 months (interquartile range, 12-80 months). When we evaluate the continuous electroencephalographic monitoring data, 27 (30.7%) were lateralized, 20 (22.7%) were multifocal, 30 (34.1%) were generalized, and 11 (12.5%) were bilateral independent epileptic activity. Seventy nine patients (89.8%) were evaluated as convulsive status epilepticus (CSE) and 9 (10.2%) as nonconvulsive status epilepticus (NCSE). Pediatric Risk of Mortality (PRISM III) score and mortality of patients with NCSE were higher ( P = 0.004 and P = 0.046, respectively). Thirteen eight patients (43.1%) were diagnosed as SE, 38 patients (43.1%) as refractory SE, and 12 patients (13.6%) as super-refractory SE. The overall mortality rate was 10.2%.

CONCLUSIONS

Status epilepticus is a neurological emergency that causes mortality and morbidity. Electroencephalographic monitoring is important for the recognition of seizures and rapid intervention. No superiority of second-line treatments or combined treatments was demonstrated in patients with SE.

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.

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.

Long-term outcomes of adult cryptogenic febrile infection-related epilepsy syndrome (FIRES)

Background

Cryptogenic febrile infection-related epilepsy syndrome (FIRES) is a rare but catastrophic encephalopathic condition. We aimed to investigate the long-term outcome in adult cryptogenic FIRES.

Methods

This was a retrospective study based on the prospective database in the neuro-intensive care unit of a tertiary hospital in China. Consecutive adult patients with cryptogenic FIRES between July 2007 to December 2021 were included. Long-term outcomes included function independence, the development of drug-resistant epilepsy (DRE), remote recurrent status epilepticus (SE), anti-seizure medications (ASMs), and changes in the brain Magnetic Resonance Imaging (MRI).

Results

A total of 11 adult patients with cryptogenic FIRES were identified from 270 patients with SE. Four (36%) patients died in the hospital, with three of them withdrawing treatments, and one patient died 12 months after discharge. After the follow-up ranging from 12 to 112 months, 6 (55%) patients were still alive, and all of them achieved functional independence [modified Rankin Scale (mRS) 0-3]. 45% (5/11) patients developed DRE, 18% (2/11) had remote recurrent SE, and 55% (6/11) were on polytherapy with ASMs at the last follow-up. Most of the patients with initial normal or abnormal MRI had abnormalities in the hippocampus at follow-up, and most of the other MRI abnormalities found in the acute stage disappeared over time.

Conclusion

The outcome of adult cryptogenic FIRES is daunting. More than one-third of patients die in the hospital. Survivors of cryptogenic FIRES may regain functional independence, but they usually develop DRE and receive polytherapy of ASMs for a long time.

New-onset refractory status epilepticus (NORSE) in paediatric patients: causes, characteristics and outcomes

Background

New-onset refractory status epilepticus (NORSE) refers to patients without a previous history of seizures who have refractory status epilepticus for at least 72 hours without an identified aetiology. Despite the severe neurological sequelae of NORSE, little is known about this condition in paediatric patients.

Objective

To describe the profile of paediatric patients with NORSE, the profile of seizures, possible causes attributed to this condition, treatments offered to patients and the outcomes at discharge from the paediatric intensive care unit (PICU).

Methods

This retrospective, multicentre, descriptive study (case series) was conducted in the PICUs of three tertiary hospitals. We reviewed the medical records of all patients aged 0–16 years admitted to the participating PICUs between December 2013 and December 2017 with refractory status epilepticus, without a previous history of seizures or neurological disease.

Results

Fifteen patients (2.4%) had NORSE. The median age of patients was 62.3 (IQR 26.2–75.4) months. All patients experienced prodromes before progressing to refractory status epilepticus. Twelve patients (80%) had fever up to 24 hours before seizures. NORSE was classified as cryptogenic in 66% of patients. Twelve patients were treated with complementary therapies, in addition to anticonvulsants. There was no standardisation in the treatment of patients. The overall mortality rate was 20%.

Conclusions

NORSE is associated with high morbidity and mortality, without an identified aetiology in most cases and with a wide range of proposed therapies.

LncRNA ZFAS1 regulates the hippocampal neurons injury in epilepsy through the miR-15a-5p/OXSR1/NF-κB pathway

Long non-coding RNAs (lncRNAs) have been confirmed to be involved in epilepsy development. It has been reported that lncRNA ZFAS1 plays a vital regulatory role in epilepsy progression. Therefore, the role and molecular mechanism of ZFAS1 in epilepsy progression deserve further investigation. Mice status epilepticus (SE) model was constructed, and hippocampal neurons were isolated from mice hippocampus tissues. The expression of ZFAS1, miR-15a-5p and oxidative stress responsive 1 (OXSR1) were determined by quantitative real-time PCR. ELISA assay was used to detect the concentrations of inflammation factors. Cell viability and apoptosis were examined by MTT assay, EdU staining and flow cytometry. Western blot analysis was conducted to measure protein levels, and the productions of SOD and MDA were measured to assess cell oxidative stress. Dual-luciferase reporter assay and RIP assay were employed to validate the relationship between miR-15a-5p and ZFAS1 or OXSR1. LncRNA ZFAS1 was highly expressed in SE mice and SE-stimulated hippocampal neurons. Silenced ZFAS1 promoted viability, while inhibited inflammation, apoptosis and oxidative stress in SE-induced hippocampal neurons. MiR-15a-5p could be targeted by ZFAS1, and its inhibitor also reversed the suppressive effect of ZFAS1 knockdown on SE-induced hippocampal neurons injury. In addition, OXSR1 was a target of miR-15a-5p, and its silencing also could relieve SE-induced hippocampal neurons injury. OXSR1 overexpression reversed the inhibition effect of miR-15a-5p on SE-induced hippocampal neurons injury. Moreover, ZFAS1 positively regulated OXSR1 expression by sponging miR-15a-5p, thereby activating the NF-κB pathway. LncRNA ZFAS1 might contribute to the progression of epilepsy by regulating the miR-15a-5p/OXSR1/NF-κB pathway.

The Frequency of Refractory Status Epilepticus and Its Outcome in a Tertiary Care Hospital in Pakistan: A Retrospective Study

Background

Refractory status epilepticus (RSE) is a common neurologic emergency with refractory cases leading to increased rates of morbidity and mortality in patients. The lack of previous studies on the incidence, causes, and management of refractory status epilepticus in the pediatric population from our region prompted us to investigate further in this study.

Methods

We included retrospective data of all patients admitted to the pediatric intensive care unit (PICU) with a provisional diagnosis of RSE at a tertiary care hospital in Karachi from February 2019 to February 2021. No personal identification data was used, and confidentiality of the data was maintained throughout the analysis. The Statistical Package for the Social Sciences (SPSS) software version 22.0 (IBM SPSS Statistics, Armonk, NY, USA) was used to pool data and perform a descriptive analysis.

Results

Among the 687 patients who presented to the PICU with seizures, 50 (7.27%) patients were eventually diagnosed with RSE during the two-year period. The majority of the patients were male and less than one year of age. Infectious causes predominated our data cohort, and a four-drug regimen consisting of phenytoin, levetiracetam, valproic acid, and midazolam was able to terminate RSE in the majority of the patients in our setting (70%). The mortality rate was noted to be 22% among patients with RSE.

Conclusion

Morbidity and mortality among pediatric RSE patients are high in our settings. Urgent emergency services and timely cause-directed intervention could improve outcomes.

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.

A retrospective study of 92 children with new-onset refractory status epilepticus

Little is known of the etiology, course, and treatment of new-onset refractory status epilepticus (NORSE) in children. Here we identified etiologies, electroencephalography (EEG) characteristics, and neuroimaging findings among pediatric patients with NORSE and among two patient subgroups, febrile infection-related epilepsy syndrome (FIRES) group and non-FIRES group. We also examined treatments and risk factors related to poor prognosis. Ninety-two children with NORSE were identified in Children's Hospital of Chongqing Medical University between January 1, 2010 and September 1, 2020. The end date was chosen to guarantee at least a 6-month follow-up. Our results indicated that patients with FIRES account for 90% of pediatric patients with NORSE. The clinical, EEG, and neuroimaging results and prognosis were not significantly different between the FIRES group and non-FIRES group of individuals. 68.5% of our patients had unknown etiology, and viral etiology was the most common identified cause (26.1%). Electroencephalography might have a certain diagnostic value for NORSE. A gradual increase in seizure burden was obvious from the onset of disease, and continuous or recurrent ictal discharge lasting ≥ 30 min was quite common in our study. The mortality was 22.8% in our study. Among the 71 surviving patients, the outcome at discharge was poor but improved during follow-up, and 68.5% had good or fair outcomes at their last follow-up. A poor outcome was observed in 39 of 92 cases (42%), with 43.9% and 30% of individuals in the FIRES group and non-FIRES group, respectively, having a poor outcome. The presence of super refractory status epilepticus (SRSE), electrographic seizures and nonconvulsive status epilepticus (NCSE), and diffuse cortical edema and multifocal abnormality may be related to a poor prognosis. Our analysis did not indicate that prognosis was directly related to etiology or treatment. Management of NORSE is challenging, and the role of immunotherapy warrants further investigation.

Unraveling the enigma of new-onset refractory status epilepticus: a systematic review of aetiologies

BACKGROUND AND PURPOSE

New-onset refractory status epilepticus (NORSE) is a clinical presentation, neither a specific diagnosis nor a clinical entity. It refers to a patient without active epilepsy or other pre-existing relevant neurological disorder, with a NORSE without a clear acute or active structural, toxic or metabolic cause. This study reviews the currently available evidence about the aetiology of patients presenting with NORSE and NORSE-related conditions.

METHODS

A systematic search was carried out for clinical trials, observational studies, case series and case reports including patients who presented with NORSE, febrile-infection-related epilepsy syndrome or the infantile hemiconvulsion-hemiplegia and epilepsy syndrome.

RESULTS

Four hundred and fifty records were initially identified, of which 197 were included in the review. The selected studies were retrospective case-control (n = 11), case series (n = 83) and case reports (n = 103) and overall described 1334 patients both of paediatric and adult age. Aetiology remains unexplained in about half of the cases, representing the so-called 'cryptogenic NORSE'. Amongst adult patients without cryptogenic NORSE, the most often identified cause is autoimmune encephalitis, either non-paraneoplastic or paraneoplastic. Infections are the prevalent aetiology of paediatric non-cryptogenic NORSE. Genetic and congenital disorders can have a causative role in NORSE, and toxic, vascular and degenerative conditions have also been described.

CONCLUSIONS

Far from being a unitary condition, NORSE is a heterogeneous and clinically challenging presentation. The development and dissemination of protocols and guidelines to standardize diagnostic work-up and guide therapeutic approaches should be implemented. Global cooperation and multicentre research represent priorities to improve the understanding of NORSE.

New-Onset Refractory Status Epilepticus in Children: Etiologies, Treatments, and Outcomes

OBJECTIVES

To elucidate etiologies, treatment, functional and neurocognitive outcomes of children with new-onset refractory status epilepticus.

DESIGN

A single-center retrospective study.

SETTING

A tertiary care children's hospital.

PATIENTS

All patients between 1 month and 21 years old admitted with new-onset refractory status epilepticus between January 2004 and July 2017.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Clinical presentation, laboratory data, imaging studies, and treatments were collected during hospitalization. Outcomes were assessed at hospital discharge and follow-up in the outpatient neurology clinic based on functional and neurocognitive outcomes as well as development of epilepsy. A total of 674 unique patients presented with status epilepticus of which 40 had new-onset refractory status epilepticus. Patients were classified into either refractory status epilepticus or super-refractory status epilepticus. The etiology of most children with new-onset refractory status epilepticus remained cryptogenic. The most common identified etiology was viral (20%). None of the patients had a contributory positive neuronal antibody test. Several treatments were tried including immunotherapy which was used in half of the patients. Five patients died (12.5%) during the acute phase of their disease, with four lost to follow-up. Twenty out of the remaining 31 patients (65%) developed epilepsy and 18 (58%) had persistent neurocognitive impairment. There was no statistical significant difference in various outcome measures and various etiologies, patients' characteristics, and treatments.

CONCLUSIONS

In this single-center cohort, more than half of the children with new-onset refractory status epilepticus did not have an identifiable etiology. Unlike adult patients, the presence of positive neuronal antibody syndrome was rare. There was no difference in outcome between those with or without an identifiable etiology. As expected, patients with super-refractory status epilepticus had worse functional and neurocognitive outcomes. More standardized diagnostic and treatment algorithms are needed along with prospective multicenter studies.

Long-term outcomes after childhood convulsive status epilepticus

PURPOSE OF REVIEW

It is widely accepted that childhood convulsive status epilepticus (CSE) has associated short-term and long-term mortality and morbidity. However, the role of CSE itself on subsequent adverse outcomes is still debated. In addition, whether prolonged seizures cause any long-term hippocampal injury and developmental or memory impairment is uncertain. In this review, we aim to provide an overview of long-term outcomes after childhood CSE, highlighting data from recent literature on this subject.

RECENT FINDINGS

Long-term outcome after childhood CSE is favorable in previously normal children, with low incidence of epilepsy, motor and intellectual disability, behavioral impairment and need for special educational provision. Mesial temporal sclerosis is uncommon in children after prolonged febrile seizures. There is substantial morbidity after childhood CSE, but this is seen primarily in children with symptomatic causes and preexisting neurological abnormalities. Cause is the primary determinant of outcomes after childhood CSE and the additional effect of CSE characteristics such as seizure duration seems to be less than previously believed.

SUMMARY

Childhood CSE is associated with substantial neurological, cognitive and behavioral morbidity. Early identification of these difficulties and appropriate intervention are likely to have a major positive impact on their quality of life.

Breaking a Cycle of Dependence to Improve Neurology Education: A Qualitative Study Exploring Pediatric Residents' Perspectives

Objective. To understand pediatric residents' experiences and attitudes toward learning neurology; and to identify facilitators and barriers to learning neurology during residency. Study Design. Qualitative study using focus groups of pediatric residents at Stanford during November 2017. Focus groups were audio-recorded and transcribed verbatim. Investigators independently coded the transcripts and reconciled codes to develop themes using constant comparison associated with grounded theory. Results. Eighteen pediatric residents participated in 3 focus groups. Four themes emerged: (1) residents feel unprepared and uncomfortable; (2) intrinsic and extrinsic factors contribute to residents' dependence on neurologists; (3) residents desire more teaching; and (4) residents are motivated to overcome their dependence on neurologists and optimize their learning. Conclusion. Pediatric residents are motivated to acquire more skills to assess and manage patients with neurological conditions. They recognize key factors that contribute to a cycle of dependence that impedes their learning and offer strategies to overcome these barriers.

Unusual cause of fever, vision loss and super refractory status epilepticus in association with simian virus 40 (SV40)

We present a case of a 23-year-old man with history of fever followed by painless complete vision loss, with subsequent new-onset refractory status epilepticus (NORSE). He initially developed bilateral retinitis. A few days later, he started having focal seizures, and subsequently developed super-refractory status epilepticus, requiring anaesthetic agents. MRI brain revealed multifocal cortical and subcortical hyperintensities in occipital and temporoparietal regions without contrast enhancement. MRI repeated a month later showed new lesions with non-visualisation of some previous lesions. Finally, a brain biopsy was done which revealed presence of lymphocytic infiltrate with SV40 inclusions in oligodendrocyte. We propose the affliction of an atypical virus affecting the retina and brain grey and white matter, presenting with NORSE in our patient. Future similar cases and isolation of the virus may help in establishing the conclusive diagnosis.