Neurocritical care and target immunotherapy for 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.

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.

[Electroencephalogram characteristics of 26 children with febrile infection-related epilepsy syndrome]

OBJECTIVES

To investigate the electroencephalogram (EEG) characteristics and progression of febrile infection-related epilepsy syndrome (FIRES) in children, aiming to enhance diagnosis and treatment approaches.

METHODS

A retrospective analysis was conducted on 26 children with FIRES between May 2017 and December 2021.

RESULTS

All 26 children (100%) presented with fever at the onset, followed by frequent convulsions that rapidly progressed into convulsive status. Ventilator support was required for 22 cases (85%). During the acute phase, EEG features demonstrated the disappearance of background activity and physiological sleep cycles in all children. Diffuse slow waves and multifocal slow spike slow waves were observed as abnormal waves during the interictal period. A characteristic pattern of focal low amplitude fast wave initiation was detected in all children during seizure episodes. In the chronic phase, the background EEG activity gradually recovered, and the presence of abnormal waves was relatively limited. The characteristic pattern of focal slow wave rhythm initiation was evident during seizure episodes. Additionally, extreme δ brushes were observed in four cases (15%).

CONCLUSIONS

These findings suggest that EEG manifestations in children with FIRES exhibit distinctive patterns during the acute and chronic stages, providing significant value for early diagnosis and clinical staging. Extreme δ brushes may be one of the distinctive markers of children with FIRES.

FIRES—Pathophysiology, therapeutical approach, and outcome

Background

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

Objective/Conclusion

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

Ketogenic Diet for a Young Adult Patient With Chronic-Phase Febrile Infection-Related Epilepsy Syndrome

Febrile infection-related epilepsy syndrome (FIRES) is a rare disease, whereby refractory status epilepticus (a severe epileptic syndrome) occurs in previously healthy individuals following a febrile illness. Here, we report a patient with FIRES who received ketogenic diet (KD) therapy initiated in the chronic phase. A 21-year-old man presented with status epilepticus, following fever and headache. In the acute phase, his seizures were refractory to conventional antiepileptic drugs and were suppressed only by intravenous anesthetics. In the chronic phase, he showed frequent seizures with concurrent severe cognitive decline. Twenty-seven months after onset, the patient was started on KD. Consequently, his seizure frequency rapidly reduced while his cognitive function slowly improved, albeit incompletely. Recently, KD has been shown to both reduce seizures and improve cognitive prognoses in children with FIRES. Although early KD may help in both seizure control and cognitive prognosis, it is likely that KD can be applied to adult patients with chronic FIRES.

New onset refractory status epilepticus: State of the art

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

Sevoflurane as bridge therapy for plasma exchange and Anakinra in febrile infection-related epilepsy syndrome

Febrile infection–related epilepsy syndrome (FIRES) is a devastating immune inflammatory–mediated epileptic encephalopathy. Herein, we discuss a previously healthy 8‐year‐old boy with FIRES in whom high dosages of conventional and nonconventional anesthetics were ineffective in treating SE, as were ketogenic diet, intravenous corticosteroids, and immunoglobulins. After 29 days of prolonged SRSE, the patient was successfully treated with sevoflurane paired with plasma exchange, for a total of five days, thus obtaining a stable EEG suppression burst pattern with no adverse events. Anakinra at the dosage of 100 mg b.i.d. was started seven days after sevoflurane and plasma exchange had been discontinued and was effective in ensuring non‐recurrence of SE. Sevoflurane as bridge therapy for immunosuppressive treatment could be considered an early, safe, and effective option in treating convulsive SE in which an autoimmune‐inflammatory etiology can reasonably be hypothesized.

Hypothesis: Febrile infection-related epilepsy syndrome is a microglial NLRP3 inflammasome/IL-1 axis-driven autoinflammatory syndrome

FIRES (febrile infection-related epilepsy syndrome) is a protracted neuroinflammatory condition of obscure cause. It mainly afflicts school-age children and often leads to permanent neurological sequelae. Most treatments to date have been of limited efficacy, while ketogenic diet and anti-interleukin-1 therapy appear beneficial for some patients. Research into this clinical entity is hampered by its rarity and complexity. Nonetheless, accumulating evidence derived from basic investigations and clinical observations converges to implicate the autoinflammatory nature of this syndrome. A closer analysis of current literature suggests that microglia and the NLRP3 inflammasome might be the pivotal cellular and molecular players in FIRES pathogenesis, respectively. Through evidence synthesis, herein we formulate the working hypothesis of overactivation of microglial NLRP3 inflammasome/interleukin-1 axis as the driving event in FIRES by creating a proinflammatory and proconvulsive milieu. The reverberation between neuroinflammation and seizure forms a vicious cycle. The unique properties of microglia might also contribute to unopposed IL-1 signalling and incessant sterile neuroinflammation in this context. The potential therapeutic relevance of the proposed conceptual framework is discussed.

The role of inflammatory mediators in epilepsy: Focus on developmental and epileptic encephalopathies and therapeutic implications

In recent years, there has been an increasing interest in the potential involvement of neuroinflammation in the pathogenesis of epilepsy. Specifically, the role of innate immunity (that includes cytokines and chemokines) has been extensively investigated either in animal models of epilepsy and in clinical settings. Developmental and epileptic encephalopathies (DEE) are a heterogeneous group of epileptic disorders, in which uncontrolled epileptic activity results in cognitive, motor and behavioral impairment. By definition, epilepsy in DEE is poorly controlled by common antiepileptic drugs but may respond to alternative treatments, including steroids and immunomodulatory drugs. In this review, we will focus on how cytokines and chemokines play a role in the pathogenesis of DEE and why expanding our knowledge about the role of neuroinflammation in DEE may be crucial to develop new and effective targeted therapeutic strategies to prevent seizure recurrence and developmental regression.

An atypical case of febrile infection-related epilepsy syndrome following acute encephalitis: impact of physiotherapy in regaining locomotor abilities in a patient with neuroregression

Encephalitis refers to inflammation of the brain parenchyma. It is potentially life-threatening with the highest incidence and severity in younger children. Febrile infection-related epilepsy syndrome (FIRES) is a condition, in which a child develops a nonspecific febrile illness that may not persist when the initial seizure activity begins. However, an electroencephalogram (EEG) shows that the child is in status epilepticus. We report the case of a five-year-old male who presented with difficulty to maintain sitting posture, and inability to stand and walk without support, following viral encephalitis at the age of one year. He had motor, visual, speech and cognitive impairment along with a seizure disorder. The physiotherapy interventions including neurodevelopmental treatment (NDT) and sensory integration (SI) helped in regaining locomotion ability in the child. The study aims to assess the impact of physiotherapy interventions on regaining locomotor ability in a child with FIRES following infective encephalitis.

Protecting the blossoming brain - Neurocritical care in children

This special issue of the Biomedical Journal is entirely dedicated to the latest updates regarding the medical efforts to preserve the fragile young brain after injury. Thereby, we learn about symptoms and diseases such as different forms of epilepsy, acute encephalopathy, increased intracranial pressure, and posthaemorrhagic hydrocephalus, as well as about their origins, such as infection, autoimmune diseases, preterm birth, or abusive head trauma. Moreover, diagnosis and surveillance techniques are discussed, including ultrasound of the optic nerve sheath diameter and multimodal monitoring. Finally, we discover various established and emerging therapeutic approaches, comprising target temperature management, ketogenic diet, and immunomodulation.