Long-term neuropsychological outcomes in children with febrile infection-related epilepsy syndrome (FIRES) treated with anakinra

Trends in management of patients with new-onset refractory status epilepticus (NORSE) from 2016 to 2023: An interim analysis

In response to the evolving treatment landscape for new-onset refractory status epilepticus (NORSE) and the publication of consensus recommendations in 2022, we conducted a comparative analysis of NORSE management over time. Seventy-seven patients were enrolled by 32 centers, from July 2016 to August 2023, in the NORSE/FIRES biorepository at Yale. Immunotherapy was administered to 88% of patients after a median of 3 days, with 52% receiving second-line immunotherapy after a median of 12 days (anakinra 29%, rituximab 25%, and tocilizumab 19%). There was an increase in the use of second-line immunotherapies (odds ratio [OR] = 1.4, 95% CI = 1.1-1.8) and ketogenic diet (OR = 1.8, 95% CI = 1.3-2.6) over time. Specifically, patients from 2022 to 2023 more frequently received second-line immunotherapy (69% vs 40%; OR = 3.3; 95% CI = 1.3-8.9)-particularly anakinra (50% vs 13%; OR = 6.5; 95% CI = 2.3-21.0), and the ketogenic diet (OR = 6.8; 95% CI = 2.5-20.1)-than those before 2022. Among the 27 patients who received anakinra and/or tocilizumab, earlier administration after status epilepticus onset correlated with a shorter duration of status epilepticus (ρ = .519, p = .005). Our findings indicate an evolution in NORSE management, emphasizing the increasing use of second-line immunotherapies and the ketogenic diet. Future research will clarify the impact of these treatments and their timing on patient outcomes.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

SIGNIFICANCE

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

Second-line immunotherapy in new onset refractory status epilepticus

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

Case report: Febrile infection-related epilepsy syndrome in a 14-year-old girl with multiple organ failure and lethal outcome

We report a case of an otherwise healthy 14-year-old girl with febrile infection-related epilepsy syndrome (FIRES), multiple organ failure (MOF), and ultimately a lethal outcome. This is a rare case of FIRES with MOF and consecutive death. Only a few cases have been described in the literature. The adolescent girl was initially admitted to our pediatric emergency department with a first episode of generalized tonic-clonic seizures after a short history of fever a week before admission. Seizures progressed rapidly into refractory status epilepticus without any evidence of the underlying cause, and treatment subsequently had to be escalated to thiopental anesthesia. Since the initial diagnostics showed no promising leads, the rare syndrome of FIRES was suspected, representing a catastrophic epileptic encephalopathy linked to a prior benign febrile infection. Methylprednisolone, intravenous immunoglobulins, and a ketogenic diet were initiated. Respiratory, circulatory, kidney, and liver failure developed during treatment, requiring increasing intensive care. Multiple attempts to deescalate antiepileptic treatment resulted in recurrent status epilepticus. A cranial MRI on the 10th day of treatment revealed diffuse brain edema and no cerebral perfusion. The patient was declared dead on the 11th day of treatment. FIRES should be taken into account in previously healthy children with a new onset of difficult-to-treat seizures after a short febrile infection when no other cause is apparent. First-line treatment, besides seizure control, is the early initiation of immunomodulatory therapy and the start of a ketogenic diet. As treatment is difficult and MOF may develop, patients should be transferred to a specialized children's hospital providing full intensive care.

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

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

Mechanisms and Emerging Therapies for Treatment of Seizures in Pediatric Autoimmune Encephalitis and Autoinflammatory/Autoimmune-Associated Epilepsy

There has been increasing understanding of the role of inflammation in seizures and epilepsy, as well as targeted immunomodulatory treatments. In children, immune-mediated seizures often present acutely in the setting of autoimmune encephalitis and are very responsive to immunotherapy with low rates of subsequent epilepsy. Conversely, seizures in autoimmune-associated epilepsies, such as Rasmussen syndrome, can remain refractory to multimodal therapy, including immunomodulation. In this review, the authors discuss the presentations of immune-mediated seizures in children, underlying mechanisms, and emerging therapies.

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.

Timing of therapeutic interventions against infection-triggered encephalopathy syndrome: a scoping review of the pediatric literature

Our goal was to conduct a scoping review of the literature on the treatment of infection-triggered encephalopathy syndrome/acute encephalopathy in children, focusing on treatment targets and treatment initiation timing. We performed literature searches using PubMed for articles reporting treatments of infection-triggered encephalopathy syndrome/acute encephalopathy. We included articles describing specific treatments for acute encephalopathy with control groups. For the purpose of searching new therapies only experimentally tried in the case series, we also included case series studies without control groups in this review, if the studies contained at least two cases with clear treatment goals. Therapies were classified based on their mechanisms of action into brain protection therapy, immunotherapy, and other therapies. We operationally categorized the timing of treatment initiation as T1 (6-12 h), T2 (12-24 h), T3 (24-48 h), and T4 (>48 h) after the onset of seizures and/or impaired consciousness. Thirty articles were included in this review; no randomized control study was found. Eleven retrospective/historical cohort studies and five case-control studies included control groups with or without specific therapies or outcomes. The targeted conditions and treatment timing varied widely across studies. However, the following three points were suggested to be effective in multiple studies: (1) Careful seizure management and targeted temperature management within 12 h (T1) of onset of febrile seizure/prolonged impaired consciousness without multiple organ failure may reduce the development of acute encephalopathy with biphasic seizures and late reduced diffusion; (2) immunotherapy using corticosteroids, tocilizumab, or plasma exchange within 24 h (T1-T2) of onset of acute necrotizing encephalopathy may reduce sequelae; and (3) anakinra therapy and ketogenic diet demonstrate little evidence of neurologic sequelae reduction, but may reduce seizure frequency and allow for weaning from barbiturates, even when administered weeks (T4) after onset in children with febrile infection-related epilepsy syndrome. Although available studies have no solid evidence in the treatment of infection-triggered encephalopathy syndrome/acute encephalopathy, this scoping review lays the groundwork for future prospective clinical trials.

Long-term outcomes in refractory status epilepticus

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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