Dietary Management of Children With Super-Refractory Status Epilepticus: A Systematic Review and Experience in a Single UK Tertiary Centre

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.

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.

Choice of pharmaceutical form as a key factor during ketogenic diet: a case report

West syndrome is a severe epilepsy syndrome characterised by the appearance of drug-resistant epileptic disorders associated with hypsarrhythmia and intellectual disability. Among non-pharmacological treatments, the ketogenic diet, which consists of low carbohydrate intake and a rich lipid intake, stands out. This treatment induces a state of ketosis, which has been related to a decrease in the number of seizures. It is essential to control the carbohydrate intake within drug treatment for these patients since many pharmaceutical forms, specifically liquid oral medication, may contain carbohydrates in the form of mono/polysaccharides or polyols. We describe the case report of an infant with drug-resistant West syndrome, treated with a ketogenic diet, whose antiseizure liquid medication impeded a proper response to the diet. After the substitution of these medications, the patient showed a remarkable decrease in the number of seizures.

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.

Ketogenic diet for super-refractory status epilepticus (SRSE) with NORSE and FIRES: Single tertiary center experience and literature data

Background and purpose

Ketogenic diet (KD) is an emerging treatment option for super-refractory status epilepticus (SRSE). We evaluated the effectiveness of KD in patients presenting SRSE including NORSE (and its subcategory FIRES).

Methods

A retrospective review of the medical records was performed at the Necker Enfants Malades Hospital. All children with SRSE in whom KD was started during the last 10 years were included. A systematic search was carried out for all study designs, including at least one patient of any age with SRSE in whom KD was started. The primary outcome was the responder rate and Kaplan-Meier survival curves were generated for the time-to-KD response. As secondary outcomes, Cox proportional hazard models were created to assess the impact of NORSE-related factors on KD efficacy.

Results

Sixteen children received KD for treatment of SRSE, and three had NORSE presentation (one infectious etiology, two FIRES). In medical literature, 1,613 records were initially identified, and 75 were selected for review. We selected 276 patients receiving KD during SRSE. The most common etiology of SRSE was acute symptomatic (21.3%), among these patients, 67.7% presented with NORSE of immune and infectious etiologies. Other etiologies were remote symptomatic (6.8%), progressive symptomatic (6.1%), and SE in defined electroclinical syndromes (14.8%), including two patients with genetic etiology and NORSE presentation. The etiology was unknown in 50.7% of the patients presenting with cryptogenic NORSE, of which 102 presented with FIRES. Overall, most patients with NORSE benefit from KD (p < 0.004), but they needed a longer time to achieve RSE resolution after starting KD compared with other non-NORSE SRSE (p = 0.001). The response to KD in the NORSE group with identified etiology compared to the cryptogenic NORSE was significantly higher (p = 0.01), and the time to achieve SE resolution after starting KD was shorter (p = 0.04).

Conclusions

The search for underlying etiology should help to a better-targeted therapy. KD can have good efficacy in NORSE; however, the time to achieve SE resolution seems to be longer in cryptogenic cases. These findings highlight the therapeutic role of KD in NORSE, even though this favorable response needs to be better confirmed in prospective controlled studies.

Management and prognosis of pediatric status epilepticus

Background

Pediatric status epilepticus is a neurological emergency with the potential for severe developmental and neurological consequences. Prompt diagnosis and management are necessary.

Objectives

To outline the existing best available evidence for managing pediatric and neonatal status epilepticus, in the light of emerging randomized controlled studies. We also focus on short and long-term prognoses.

Materials and methods

This is a systematic overview of the existing literature.

Results

Status epilepticus, its treatment, and prognosis are usually based on the continuation of seizure activity at 5 and 30 min. Refractory and super-refractory status epilepticus further complicates management and requires continuous EEG monitoring with regular reassessment and adjustment of therapy. Benzodiazepines have been accepted as the first line of treatment on the basis of reasonable evidence. Emerging randomized controlled trials demonstrate equal efficacy for parenterally administered phenytoin, levetiracetam, and valproic acid as second-line agents. Beyond this, the evidence for third-line options is sparse. However, encouraging evidence for midazolam and ketamine exists with further data required for immunological, dietary, and surgical interventions.

Conclusion

Our overview of the management of pediatric and neonatal status epilepticus based on available evidence emphasizes the need for evidence-based guidelines to manage status epilepticus that fails to respond to second-line treatment.

Modified low ratio ketogenic therapy in the treatment of adults with super-refractory status epilepticus

BACKGROUND

Induction of ketosis by manipulation of nutrition intake has been proposed as an adjunctive treatment for super-refractory status epilepticus (SRSE). However, the classical 4:1 ketogenic ratio may not meet the nutrition needs, specifically protein for critically ill adults. The aim of this study was to analyze the outcomes of adults with SRSE who received a lower ketogenic ratio of 2:1 grams of fat to non-fat grams, including 20%-30% of energy from medium chain triglycerides.

METHODS

We reviewed patients aged ≥18 years with SRSE treated with ketogenic therapy between July 2015 and December 2020 at two quaternary teaching hospitals in Melbourne, Australia. Data collected from medical records included patient demographics, nutrition prescription, clinical outcomes, and ketogenic therapy-related complications. The primary outcome of the study was to assess tolerability of ketogenic therapy.

RESULTS

Twelve patients (female = 7) were treated with ketogenic therapy for SRSE. Patients received between 4 and 8 antiseizure medications and 1-5 anesthetic agents prior to commencement of ketogenic therapy. Blood beta-hydroxybutyrate concentrations were variable (median = 0.5 mmol/L, range: 0.0-6.1 mmol/L). SRSE resolved in 10 cases (83%) after a median of 9 days (range: 2-21 days) following commencement of ketogenic therapy. Ketogenic therapy-associated complications were reported in five patients, leading to cessation in two patients.

CONCLUSION

Despite the challenge in maintaining ketosis during critical illness, low ratio 2:1 ketogenic therapy incorporating medium chain triglycerides is tolerable for adults with SRSE. Further studies are required to determine the optimal timing, nutrition prescription and duration of ketogenic therapy for SRSE treatment.

Chinese expert recommendations on ketogenic diet therapy for super-refractory status epilepticus

Super-refractory status epilepticus (SRSE) is a serious and life-threatening neurological condition. Ketogenic diet (KD) is a diet characterized by high fat, low carbohydrate, and moderate protein. As KD shows effectiveness in controlling seizures in more than half of SRSE patients, it can be a treatment option for SRSE. Currently, KD treatment for SRSE is based on personal experience and observational evidence has been published. In the context of a lack of a validated guideline, we convened a multicenter expert panel within the China Association Against Epilepsy (CAAE) Ketogenic Diet Commission to work out the Chinese expert recommendations on KD for SRSE. We summarize and discuss the latest clinical practice of KD for SRSE in critical care settings. Recommendations are given on patient selection, the timing of KD, diet implementation, and follow-up. More research data are needed in this area to support better clinical practice.

Neuroprotection by the Ketogenic Diet: Evidence and Controversies

The ketogenic diet (KD) is a high-fat low-carbohydrate diet that has been used for decades as a non-pharmacologic approach to treat metabolic disorders and refractory pediatric epilepsy. In recent years, enthusiasm for the KD has increased in the scientific community due to evidence that the diet reduces pathology and improves various outcome measures in animal models of neurodegenerative disorders, including multiple sclerosis, stroke, glaucoma, spinal cord injury, retinal degenerations, Parkinson's disease and Alzheimer's disease. Clinical trials also suggest that the KD improved quality of life in patients with multiple sclerosis and Alzheimer's disease. Furthermore, the major ketone bodies BHB and ACA have potential neuroprotective properties and are now known to have direct effects on specific inflammatory proteins, transcription factors, reactive oxygen species, mitochondria, epigenetic modifications and the composition of the gut microbiome. Neuroprotective benefits of the KD are likely due to a combination of these cellular processes and other potential mechanisms that are yet to be confirmed experimentally. This review provides a comprehensive summary of current evidence for the effectiveness of the KD in humans and preclinical models of various neurological disorders, describes molecular mechanisms that may contribute to its beneficial effects, and highlights key controversies and current gaps in knowledge.

Ketogenic diet as elective treatment in patients with drug-unresponsive hyperinsulinemic hypoglycemia caused by glucokinase mutations

Background

Hyperinsulinemic hypoglycemia (HI) is the most frequent cause of recurrent hypoglycemia in children. Despite diagnostic and therapeutic advances, it remains an important cause of morbidity, leading to neurological complications, such as psychomotor retardation and epilepsy. Patients with diffuse drug-unresponsive HI manifest neurological impairment and neurobehavioral problems, even though surgically treated with a near-total pancreatectomy. Based on the analogies between HI and GLUT1 deficiency, both presenting with neuroglycopenia and lack of alternative cerebral energy sources, we administered a ketogenic diet (KD) in three drug-unresponsive GCK-HI patients with the aim of preserving neurodevelopment and avoiding the need of a near-total pancreatectomy. They presented recurrent symptomatic hypoglycemia, intellectual disability and refractory epilepsy. Patients were treated with classical KD for 79, 27 and 18 months, respectively.

Results

All patients became asymptomatic in a few days and showed an important improvement of the alert state. Epilepsy disappeared and no appearance of novel hypoglycemic lesions was detected with a brain MRI. Cognitive and adaptive abilities rapidly improved and normalized. IQ rose significantly from 81 to 111 (p = 0.04) in patient 1, from 82 vs 95 (p = 0.04) in patient 2, from 60 to 90 (p = 0.04) in patient 3.

Conclusions

We demonstrated the safety and efficacy of KD in the treatment of drug-unresponsive GCK-HI at a short and long-term. The neuroprotective effects of KD determined the recovery from epilepsy and intellectual disabilities and averted the need of a near-total pancreatectomy. All patients and their families reported an improvement of physical and psychosocial well-being, with a substantial improvement of their quality of life. These results might change the course and the quality of life of these patients and their families, having a relevant impact on human lives. Therefore, KD might be considered the elective treatment in unresponsive forms of GCK-HI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-02045-3.

Effects of a low-carbohydrate ketogenic diet on reported pain, blood biomarkers and quality of life in patients with chronic pain: A pilot randomised clinical trial

BACKGROUND

A low-carbohydrate ketogenic diet has been reported to improve chronic pain by reducing inflammation, oxidative stress, and sensitivity within the nervous system. The main aim of this trial is to evaluate the effects of a ketogenic diet on reported pain, blood biomarkers and quality of life in patients with chronic pain.

METHODS

Participants with chronic musculoskeletal pain were recruited for a 12-week diet intervention that commenced with a 3-week run-in diet removing ultra-processed foods, followed by randomisation to either a whole-food/well-formulated ketogenic diet (WFKD) or to continue with the minimally processed whole-food diet (WFD). Outcome measures included: average pain (visual analogue scale VAS), blood biomarkers, anthropometrics, adherence, depression, anxiety, sleep, ketones, quality of life, diet satisfaction and macronutrient intake.

RESULTS

Average weekly pain improved for both groups. WFKD group VAS reduced by 17.9 ± 5.2 mm (p = 0.004) and the WFD group VAS reduced 11.0 ± 9.0 mm (p = 0.006). Both groups also reported improved quality of life (WFKD = 11.5 ± 2.8%, p = 0.001 and WFD = 11.0 ± 3.5%, p = 0.014). The WFKD group also demonstrated significant improvements in pain interference (p = 0.013), weight (p < 0.005), depression (p = 0.015), anxiety (p = 0.013), and inflammation (hsCRP) (p = 0.009). Significant average pain reduction remained at three-month follow-up for both groups (WFKD p = 0.031, WFD p = 0.011).

CONCLUSION

The implementation of a whole-food diet that restricts ultra-processed foods is a valid pain management tool, however a low-carbohydrate ketogenic diets may have potentially greater pain reduction, weight loss and mood improvements.

Stuttering: A Disorder of Energy Supply to Neurons?

Stuttering is a disorder characterized by intermittent loss of volitional control of speech movements. This hypothesis and theory article focuses on the proposal that stuttering may be related to an impairment of the energy supply to neurons. Findings from electroencephalography (EEG), brain imaging, genetics, and biochemistry are reviewed: (1) Analyses of the EEG spectra at rest have repeatedly reported reduced power in the beta band, which is compatible with indications of reduced metabolism. (2) Studies of the absolute level of regional cerebral blood flow (rCBF) show conflicting findings, with two studies reporting reduced rCBF in the frontal lobe, and two studies, based on a different method, reporting no group differences. This contradiction has not yet been resolved. (3) The pattern of reduction in the studies reporting reduced rCBF corresponds to the regional pattern of the glycolytic index (GI; Vaishnavi et al., 2010). High regional GI indicates high reliance on non-oxidative metabolism, i.e., glycolysis. (4) Variants of the gene ARNT2 have been associated with stuttering. This gene is primarily expressed in the brain, with a pattern roughly corresponding to the pattern of regional GI. A central function of the ARNT2 protein is to act as one part of a sensor system indicating low levels of oxygen in brain tissue and to activate appropriate responses, including activation of glycolysis. (5) It has been established that genes related to the functions of the lysosomes are implicated in some cases of stuttering. It is possible that these gene variants result in a reduced peak rate of energy supply to neurons. (6) Lastly, there are indications of interactions between the metabolic system and the dopamine system: for example, it is known that acute hypoxia results in an elevated tonic level of dopamine in the synapses. Will mild chronic limitations of energy supply also result in elevated levels of dopamine? The indications of such interaction effects suggest that the metabolic theory of stuttering should be explored in parallel with the exploration of the dopaminergic theory.