Effect of topiramate, in combination with lidocaine, and phenobarbital, in acute encephalitis with refractory repetitive partial seizures

Lidocaine as a potential therapeutic option for super-refractory status epilepticus: A case report

New-onset refractory status epilepticus (NORSE) is a rare and devastating condition and the prognosis is often poor, with half to two-thirds of survivors experiencing drug-resistant epilepsy, residual cognitive impairment, or functional disability, and the mortality rate is 16% to 27% for adults. We describe a patient with cryptogenic NORSE and favorable recovery from drug-resistant super-refractory SE after the use of intravenous lidocaine. The patient experienced fever and presented with refractory generalized tonic-clonic seizures. The cause was not found by performing extensive examinations, including cell surface autoantibodies and rat brain immunohistochemistry evaluations. The refractory SE with unresponsiveness to multiple anti-epileptic and prolonged sedative medications, which are necessary for prolonged mechanical ventilation, were ameliorated by additive treatment with intravenous lidocaine initiating at 1 mg/kg/h and maintaining at 2 mg/kg/h for 40 days, which led to freedom from intravenous sedative medication and mechanical ventilation. The patient was able to return to school. Lidocaine may be an optional treatment for cryptogenic NORSE.

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.

Acute encephalopathy with biphasic seizures and late reduced diffusion: Predictive EEG findings

BACKGROUND

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a common type of acute encephalopathy in Japan; the condition is clinically characterized by prolonged seizures as the initial neurological symptom, followed by late seizures 4-6 days later. It is difficult to differentiate AESD from prolonged febrile seizures (PFSs). Here, we explored the use of electroencephalography to differentiate AESD from PFSs.

METHODS

We studied the electroencephalograms (EEGs) of children <6 years of age diagnosed with AESD or PFSs; all EEGs were recorded within 48 h of seizure onset (i.e., before the late seizures of AESD). Two pediatric neurologists evaluated all EEGs, focusing on the basic rhythm, slowing during wakefulness/arousal by stimuli, spindles, fast waves, and slowing during sleep.

RESULTS

The EEGs of 14 children with AESD and 31 children with PFSs were evaluated. Spindles were more commonly reduced or absent in children with AESD than in those with PFSs (71% vs. 31%, p = 0.021). Fast waves were also more commonly reduced or absent in children with AESD (21% vs. 0%, p = 0.030). The rates of all types of slowing did not differ between children with AESD and those with PFSs, but continuous or frequent slowing during sleep was more common in the former (50% vs. 17%, p = 0.035).

CONCLUSIONS

EEG findings may usefully differentiate AESD from PFSs. Reduced or absent spindles/fast waves and continuous or frequent slowing during sleep are suggestive of AESD in children with prolonged seizures associated with fever.

Guidelines for the diagnosis and treatment of acute encephalopathy in childhood

The cardinal symptom of acute encephalopathy is impairment of consciousness of acute onset during the course of an infectious disease, with duration and severity meeting defined criteria. Acute encephalopathy consists of multiple syndromes such as acute necrotizing encephalopathy, acute encephalopathy with biphasic seizures and late reduced diffusion and clinically mild encephalitis/encephalopathy with reversible splenial lesion. Among these syndromes, there are both similarities and differences. In 2016, the Japanese Society of Child Neurology published 'Guidelines for the Diagnosis and Treatment of Acute Encephalopathy in Childhood', which made recommendations and comments on the general aspects of acute encephalopathy in the first half, and on individual syndromes in the latter half. Since the guidelines were written in Japanese, this review article describes extracts from the recommendations and comments in English, in order to introduce the essence of the guidelines to international clinicians and researchers.

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.

Therapeutic burst-suppression coma in pediatric febrile refractory status epilepticus

BACKGROUND

Evidence for the beneficial effect of therapeutic burst-suppression coma in pediatric patients with febrile refractory status epilepticus is limited, and the clinical outcomes of this treatment strategy are largely unknown. Therefore, the aim of this study was to explore the outcomes of therapeutic burst-suppression coma in a series of children with febrile refractory status epilepticus.

METHODS

We retrospectively reviewed consecutive pediatric patients with febrile refractory status epilepticus admitted to our pediatric intensive care unit between January 2000 and December 2013. The clinical characteristics were analyzed.

RESULTS

Thirty-five patients (23 boys; age range: 1-18years) were enrolled, of whom 28 (80%) developed super-refractory status epilepticus. All of the patients received the continuous administration of intravenous antiepileptic drugs for febrile refractory status epilepticus, and 26 (74.3%) achieved therapeutic burst-suppression coma. All of the patients received mechanical ventilatory support, and 26 (74.3%) received inotropic agents. Eight (22.9%) patients died within 1month. The neurologically functional outcomes at 6months were good in six (27.3%) of the 22 survivors, of whom two returned to clinical baseline. The patients with therapeutic burst-suppression coma were significantly associated with hemodynamic support than the patients with electrographic seizures control (p=0.03), and had a trend of higher 1-month mortality rate, worse 6months outcomes, and a longer duration of hospitalization.

CONCLUSIONS

Our results suggest that therapeutic burst-suppression coma to treat febrile refractory status epilepticus may lead to an increased risk of hemodynamic instability and a trend of worse outcomes.

Analysis of Fulminant Cerebral Edema in Acute Pediatric Encephalitis

BACKGROUND

Acute pediatric encephalitis with fulminant cerebral edema can rapidly become fatal or result in devastating neurological sequelae.

METHODS

All cases coded with the discharge diagnosis of acute encephalitis between January 2000 and December 2010 were reviewed. Of the 1038 children with acute pediatric encephalitis, 25 were enrolled in our study with ages ranging from 5 months to 16 years.

RESULTS

The major neurological symptoms included an altered level of consciousness (72%), vomiting (60%), and headache (48%). The onset of neurological symptoms to signs of brain herniation ranged from 0 days to 9 days. Nineteen (76%) patients had a seizure 24-48 hours prior to showing signs of fulminant cerebral edema, and 12 (48%) patients developed status epilepticus. Sixteen patients died, and no survivors returned to baseline. Risk factors for seizures and status epilepticus were compared between the fulminant cerebral edema group (n = 25, 19 seizures, including 12 status epilepticus) and control group (nonfulminant cerebral edema) (n = 1013, 444 seizures, including 141 status epilepticus; p = 0.001 for seizures and p < 0.001 for status epilepticus).

CONCLUSION

Our findings indicate that preceding seizures and status epilepticus are significant risk factors for fulminant cerebral edema in children with acute encephalitis.

Management of Status Epilepticus in Children

Status epilepticus is a common pediatric neurological emergency. Management includes prompt administration of appropriately selected anti-seizure medications, identification and treatment of seizure precipitant(s), as well as identification and management of associated systemic complications. This review discusses the definitions, classification, epidemiology and management of status epilepticus and refractory status epilepticus in children.

Effect of Antiepileptic Drugs for Acute and Chronic Seizures in Children with Encephalitis

BACKGROUND

Encephalitis presents with seizures in the acute phase and increases the risk of late unprovoked seizures and epilepsy. This study aimed to evaluate the effect of antiepileptic drugs in pediatric patients with acute seizures due to encephalitis and epilepsy.

PATIENTS AND METHODS

Cases of acute pediatric encephalitis between January 2000 and December 2010 were reviewed. Clinical data, including onset at age, seizure type, seizure frequency, effects of antiepileptic drugs, and prognosis were analyzed.

RESULTS

During the study period, 1038 patients (450 girls, 588 boys) were enrolled. Among them, 44.6% (463) had seizures in the acute phase, 33% had status epilepticus, and 26% (251) developed postencephalitic epilepsy. At one year of follow-up, 205 of the 251 patients with postencephalitic epilepsy were receiving antiepileptic drugs while 18% were seizure free even after discontinuing the antiepileptic drugs. Among those with postencephalitic epilepsy, 67% had favorable outcomes and were using <2 anti-epileptic drugs while 15% had intractable seizures and were using ≥ 2 antiepileptic drugs. After benzodiazepines, intravenous phenobarbital was preferred over phenytoin as treatment of postencephalitic seizures in the acute phase. For refractory status epilepticus, high-dose topiramate combined with intravenous high-dose phenobarbital or high-dose lidocaine had less side effects.

CONCLUSIONS

Children with encephalitis have a high rate of postencephalitic epilepsy. Phenobarbital and clonazepam are the most common drugs used, alone or in combination, for postencephalitic epilepsy.

Flupirtine effectively prevents development of acute neonatal seizures in an animal model of global hypoxia

Current first-line drugs for the treatment of neonatal seizures have limited efficacy and are associated with side effects. Uncontrolled seizures may exacerbate brain injury and contribute to later-life neurological disability. Therefore, it is critical to develop a treatment for neonatal seizures that is effective and safe. In early-life, when the γ-aminobutyric acid (GABA) inhibitory system is not fully developed, potassium channels play an important role in controlling excitability. An earlier study demonstrated that flupirtine, a KCNQ potassium channel opener, is more efficacious than diazepam and phenobarbital for the treatment of chemoconvulsant-induced neonatal seizures. In newborns, seizures are most commonly associated with hypoxic-ischemic encephalopathy (HIE). Thus, in the present study, we examined the efficacy of flupirtine to treat neonatal seizures in an animal model of global hypoxia. Our results showed that flupirtine dose dependently blocks the occurrence of behavioral seizures in pups during hypoxia. Additionally, flupirtine inhibits the development of hypoxia-induced clinical seizures and associated epileptiform discharges, as well as purely electrographic (subclinical) seizures. These results suggest that flupirtine is an effective anti-seizure drug, and that further studies should be conducted to determine the time window within which it's administration can effectively treat neonatal seizures.

Lidocaine for Status Epilepticus in Pediatrics

BACKGROUND

Our goal was to perform a systematic review of the literature on the use of intravenous lidocaine in pediatrics for status epilepticus (SE) and refractory status epilepticus (RSE) to determine its impact on seizure control.

METHODS

All articles from MEDLINE, BIOSIS, EMBASE, Global Health, HealthStar, Scopus, Cochrane Library, the International Clinical Trials Registry Platform (inception to November 2014), and gray literature were searched. The strength of evidence was adjudicated using both the Oxford and Grading of Recommendations Assessment, Development, and Evaluation methodologies by two independent reviewers.

RESULTS

Overall, 20 original studies were identified, with 19 manuscripts and one meeting abstract. Two hundred and thirty-five pediatric patients were treated for 252 episodes of SE/RSE. Patients had varying numbers of antiepileptic drugs (two to eight) on board before lidocaine therapy. During 20 of the 252 (7.9%) episodes of SE/RSE, phenytoin was on board. The dose regimen of lidocaine varied, with some using bolus dosing alone; others used a combination of bolus and infusion therapy. Overall, 60.0% of seizures responded to lidocaine, with complete cessation and greater than 50% reduction seen in 57.6% and 12.3%, respectively. Patient outcomes were sparingly reported.

CONCLUSIONS

There currently exists Oxford level 2b, Grading of Recommendations Assessment Development, and Evaluation C evidence to support the consideration of lidocaine for SE and RSE in the pediatric population. Further prospective studies of lidocaine administration in this setting are warranted.

Effect of levetiracetam in acute encephalitis with refractory, repetitive partial seizures during acute and chronic phase

AIM

To clarify the effect of levetiracetam (LEV) for acute and chronic seizure control in acute encephalitis with refractory, repetitive partial seizures (AERRPS).

METHODS

We retrospectively reviewed the clinical course of six AERRPS cases treated with LEV, and explored the acute phase termination by withdrawal from barbiturate-induced coma under artificial ventilation, and the reduction in seizure frequency during the chronic phase. LEV was administrated orally or via nasogastric tubes as an add-on agent during acute (n=3; age 8-10 years) and chronic (n=3; age 19-30 years) AERRPS.

RESULTS

In the acute phase, administration of LEV (50-60 mg/kg/d) in combination with phenobarbital (n=3; peak 57.9-76.1 μg/ml) and potassium bromide (n=2; 30-36 mg/kg/d)) resulted in successful reduction of intravenous barbiturate dosage and withdrawal from artificial ventilation. In the chronic phase, seizure frequency reduced by >75% for 5-18 months with LEV 750-1500 mg/d.

CONCLUSION

LEV may affect seizure control in AERRPS, particularly during the chronic phase, through its unique action of inhibition of excitatory neurotransmitter release. The regimen of oral barbiturate, potassium bromide and LEV would be worth for trial during the acute phase of AERRPS.

Status epilepticus and refractory status epilepticus management

Status epilepticus (SE) describes persistent or recurring seizures without a return to baseline mental status and is a common neurologic emergency. SE can occur in the context of epilepsy or may be symptomatic of a wide range of underlying etiologies. The clinician's aim is to rapidly institute care that simultaneously stabilizes the patient medically, identifies and manages any precipitant conditions, and terminates seizures. Seizure management involves "emergent" treatment with benzodiazepines followed by "urgent" therapy with other antiseizure medications. If seizures persist, then refractory SE is diagnosed and management options include additional antiseizure medications or infusions of midazolam or pentobarbital. This article reviews the management of pediatric SE and refractory SE.

Management of pediatric status epilepticus

OPINION STATEMENT

Status epilepticus (SE) is a medical emergency consisting of persistent or recurring seizures without a return to baseline mental status. SE can be divided into subtypes based on seizure types and underlying etiologies. Management should be implemented rapidly and based on pre-determined care pathways. The aim is to terminate seizures while simultaneously identifying and managing precipitant conditions. Seizure management involves "emergent" treatment with benzodiazepines (lorazepam intravenously, midazolam intramuscularly, or diazepam rectally) followed by "urgent" therapy (phenytoin/fosphenytoin, phenobarbital, levetiracetam or valproate sodium). If seizures persist, "refractory" treatments include infusions of midazolam or pentobarbital. Prognosis is dependent on the underlying etiology and seizure persistence. This article reviews the current management strategies for pediatric convulsive SE.

Antineuronal antibodies and infectious pathogens in severe acute pediatric encephalitis

The pathogenesis of acute encephalitis is divided into either direct infection or by immune-mediated inflammation, but the cause is still unknown. This retrospective study aimed to screen antineuronal antibodies in children with severe acute encephalitis. Thirty-four children (22 boys and 12 girls) underwent assessments such as antineuronal antibodies survey for autoimmune encephalitis and polymerase chain reaction/viral culture and antibody assays for all commonly recognized causes of infectious encephalitis. Sixteen (47.1%) were positive for autoantibodies, including antiglutamic acid decarboxylase antibodies in 16 and voltage-gated potassium channel complex antibodies in 1. Sixteen patients (47.1%) had presumed infectious etiologies, including 6 with influenza, 6 with Mycoplasma pneumoniae, 3 with enterovirus, and 1 with herpes simplex virus. In this study, influenza and Mycoplasma pneumoniae infection are the main presumed causes of severe acute encephalitis in children, although an immune-mediated mechanism may also play a role.

Limbic encephalitis in Taiwanese children and adolescence: a single center study

BACKGROUND

Non-viral limbic encephalitis, which may be paraneoplastic or idiopathic, is increasingly recognized in adults and children. Early identification of potential patients, who have neuronal autoantibodies to intracellular or neuronal surface antigens in order to give appropriate immunotherapy, is key to improving the prognosis. This cross-sectional study describes the clinical manifestation and the serological evidence of the presence of neuronal antibodies in Taiwanese children with limbic encephalitis.

METHOD

We enrolled children and adolescents who had been hospitalized due to nonviral limbic encephalitis. Serum samples from these patients were collected to screen antibodies against intracellular antigens [amphiphysin, Ma2, Ri, Yo, Hu and antiglutamic acid decarboxylase (GAD)] and neuronal surface antigens [N-methyl-d-aspartate (NMDA) receptor, γ-amino butyric acid (GABAB) receptor and voltage-gated potassium channel complexes (VGKCs)].

RESULTS

All of the 10 enrolled patients had acute onset of fever and rapid clinical deterioration. They had persistent neuropsychiatric symptoms and 90% developed refractory epilepsy, despite six patients having been treated with methylprednisolone pulse therapy or intravenous immunoglobulin (IVIG) at the acute stage. In the laboratory findings, half of the cases were positive for antibodies with regards to intracellular antigens (amphiphysin or GAD). The general outcomes, assessed by Glasgow Outcome Scale, were similar between patients with and those without the antibodies (Mann-Whitney U test, p = 0.43). One patient, who was positive for antibodies to amphiphysin 10 years after disease onset, still had a significant response to oral prednisolone therapy. At the end of the follow-up period, no cancer or insulin-dependent diabetes mellitus was detected in any of the patients.

CONCLUSION

This study provides evidence for a potential association between antibodies and limbic encephalitis. The presence of antibodies, especially antibodies to GAD, may serve as an indicator for immunotherapy.

VGKC complex antibodies in pediatric severe acute encephalitis: a study and literature review

BACKGROUND

Antibodies to surface proteins like voltage-gated potassium channel (VGKC) complexes are increasingly found in different neurologic diseases and encephalitis in adults and recently, in children. Detecting such antibodies can help identify forms of encephalitis that may respond to immuno-therapies. However, there are few reports on VGKC complex antibodies in pediatric severe acute encephalitis.

METHODS

This study retrospectively reviewed antibodies to VGKC, leucine-rich glioma-inactivated 1 (Lgi1), and contactin-associated protein-like 2 (Caspr2) in 46 children with severe acute encephalitis. Published cases of VGKC complex antibodies in pediatric encephalitis in the period of 2000-2012 were also reviewed.

RESULTS

Elevated VGKC complex antibodies (>100pM) were detected in one of the 46 children with severe acute encephalitis. The 4-year and 6-month-old girl presented with seizure and disturbed consciousness. Viral PCR/culture and serologic evidence of influenza A infection was noted. She also had complications of epilepsy, impaired cognition, and altered behavior and psychology. Antibodies to Lgi1 and Caspr2 were not detected. Ten previously published reports revealed that VGKC complex antibodies can occur in children with limbic encephalitis and acute or sub-acute encephalitis.

CONCLUSION

The incidence of VGKC complex antibodies in pediatric severe acute encephalitis is not high with only one (2.2%) of 46 children in this study. And, this is the first report on the association of VGKC complex antibodies and patients with influenza A-related severe acute encephalitis. The mechanism of VGKC complex antibodies in pediatric severe acute encephalitis warrants further study.

Antiglutamic acid decarboxylase antibodies in children with encephalitis and status epilepticus

Encephalitis may present with seizures or status epilepticus, and the etiology is usually presumed. Specific antibodies to ion channels, receptors, and other synaptic proteins were identified during the past decade. However, only a few studies investigated antiglutamic acid decarboxylase antibodies and antibodies to cell membrane ion channels or surface antigens in pediatric encephalitis and status epilepticus. We examined antibodies to glutamic acid decarboxylase and cell membrane ion channels or surface antigens in acute-phase serum from 17 children with encephalitis and status epilepticus. Antiglutamic acid decarboxylase antibody titers were compared with those of control children manifesting therapy-resistant epilepsy. Antiglutamic acid decarboxylase antibody titers were significantly higher in those with encephalitis and status epilepticus than in those with therapy-resistant epilepsy. No patient demonstrated antibodies to cell membrane ion channels or surface antigens. Six children exhibited positive antiglutamic acid decarboxylase antibodies. One child died, three manifested postencephalitic epilepsy with neurologic deficits, and two recovered well. Higher antiglutamic acid decarboxylase antibody titers were evident in the children with encephalitis and status epilepticus. Clinicians should be aware of the potential role of antiglutamic acid decarboxylase antibodies in children with encephalitis and status epilepticus.

Amplitude-integrated electroencephalography in patients with acute encephalopathy with refractory, repetitive partial seizures

We report amplitude-integrated EEG findings in two children with acute encephalopathy with refractory, repetitive partial seizures. Both patients had a febrile illness one week before the onset of seizure. They had reduction of consciousness and repetitive seizures refractory to first-line antiepileptic drugs. Seizure frequency rapidly increased and evolved into status epilepticus. Continuous seizure monitoring with amplitude-integrated EEG revealed frequent subclinical seizures which were missed by direct observation. In addition, the site of origin of seizures was multifocal, and seizure foci shifted from one hemisphere to the other. Their seizures were controlled after an administration of high-dose phenobarbital. Continuous seizure monitoring with amplitude-integrated EEG will contribute to correct estimation of seizure burden and efficacy of antiepileptic drugs in children with acute encephalopathy with refractory, repetitive partial seizures.