Risk factors for febrile status epilepticus: a case-control study

Febrile Seizures: An Updated Narrative Review for Pediatric Ambulatory Care Providers

BACKGROUND

While generally self-limited, febrile seizures result in significant familial distress. Ambulatory pediatric care providers must be prepared to counsel families on the causes, risk factors, management principles, and prognosis of children with febrile seizures.

OBJECTIVE

To provide an updated, evidence-based review of febrile seizures focused on the needs of an ambulatory pediatric care provider.

METHODS

A narrative review of the literature prioritizing landmark articles, metanalyses, longitudinal population longitudinal cohort studies and national level guidelines.

RESULTS

Febrile seizures are aberrant physiological responses to fever in children caused by complex interactions of cytokine mediated neuroinflammation, environmental triggers, and genetic predisposition. Other than investigations to determine fever etiology, routine bloodwork, lumbar punctures, neuroimaging and electroencephalograms are low yield. The general prognosis is excellent, however, clinicians should be aware of long-term outcomes including: cognitive impairment with non-simple febrile seizures; neuropsychiatric associations; recurrent febrile seizure and epilepsy risk factors; and the association between complex febrile seizures and sudden unexpected death. Children with a high risk of recurrence, complex febrile seizures, limited access to care, or extreme parental anxiety may benefit from intermittent oral diazepam prophylaxis.

CONCLUSION

Clinicians should consider four management priorities: 1) terminating the seizure; 2) excluding critical differential diagnoses; 3) investigating fever etiology; and 4) providing adequate counselling to families. The clinical approach and prognosis of febrile seizure can be based on subtype. Children with non-simple (i.e. complex or febrile status epilepticus) febrile seizures require closer care than the vast majority of children with simple febrile seizures, who have excellent outcomes.

Fever-Associated Seizures or Epilepsy: An Overview of Old and Recent Literature Acquisitions

In addition to central nervous system infections, seizures and fever may occur together in several neurological disorders. Formerly, based on the clinical features and prognostic evolution, the co-association of seizure and fever included classical febrile seizures (FS) divided into simple, complex, and prolonged FS (also called febrile status epilepticus). Later, this group of disorders has been progressively indicated, with a more inclusive term, as "fever-associated seizures or epilepsy" (FASE) that encompasses: (a) FS divided into simple, complex, and prolonged FS; (b) FS plus; (c) severe myoclonic epilepsy in infancy (Dravet syndrome); (d) genetic epilepsy with FS plus; and (e) febrile infection-related epilepsy syndrome (FIRES). Among the FASE disorders, simple FS, the most common and benign condition, is rarely associated with subsequent epileptic seizures. The correlation of FS with epilepsy and other neurological disorders is highly variable. The pathogenesis of FASE is unclear but immunological and genetic factors play a relevant role and the disorders belonging to the FASE group show to have an underlying common clinical, immunological, and genetic pathway. In this study, we have reviewed and analyzed the clinical data of each of the heterogeneous group of disorders belonging to FASE.

The Utility of Infectious and Neurodiagnostic Testing in Children With Complex Febrile Seizures Requiring Mechanical Ventilation

A retrospective cohort analysis was performed on 79 consecutive patients between 6 months and 5 years admitted to a tertiary hospital with a diagnosis of complex febrile seizures requiring mechanical ventilation from 2011 to 2017 to determine the utility of infectious and neurologic diagnostics. Intubation was used as a proxy for severity of illness. The overall intensive care unit stay was short (95% intubated <24 hours, 88% admitted <3 days). No life-threatening infections were identified, and none required surgical interventions. Electroencephalogram (EEG) was obtained on 43%, 26% of which were abnormal. Sixty-six percent of patients were discharged on rescue benzodiazepine and 20% with maintenance antiseizure medications. Duration of follow-up averaged 4 years (range 1 month to 9 years); 8 patients (10%) were subsequently diagnosed with epilepsy. Our findings suggest that extensive diagnostic evaluations may not be necessary for children with complex febrile seizures requiring mechanical ventilation although the role of EEG is less understood.

[Dynamic change of hippocampal volume in children with recurrent febrile seizures]

OBJECTIVE

To study the change and significance of hippocampal volume (HCV) in children with recurrent febrile seizures.

METHODS

A retrospective analysis was performed on the medical data and examination results of 34 children with recurrent febrile seizures who underwent two magnetic resonance plain scans of the head and the hippocampus from January 1, 2013 to September 30, 2019. According to the follow-up time, they were divided into the first follow-up group and the second follow-up group. According to prognosis, they were divided into a febrile seizure group, a non-febrile group and an epilepsy group. The change in HCV was analyzed and compared.

RESULTS

Total HCV was positively correlated with age (rs=0.683, P < 0.05). The second follow-up group had a significantly larger total HCV than the first follow-up group (P < 0.05). For both groups, preschool children (≥ 3 years old) had significantly larger total HCV, left HCV, and right HCV than those at an age of < 3 years (P < 0.05). For both groups, the children with persistent seizures had significantly lower average annual increment (ΔV) of total HCV, left HCV, and right HCV than those without persistent seizures (P < 0.05). There was no significant difference in ΔV of total HCV, left HCV, and right HCV among the febrile seizure, non-febrile seizure and epilepsy groups (P > 0.05).

CONCLUSIONS

HCV gradually increases with age in children with recurrent febrile seizures. Persistent seizures may damage the development of the hippocampus.

[Dynamic change of hippocampal volume in children with recurrent febrile seizures]

OBJECTIVE

To study the change and significance of hippocampal volume (HCV) in children with recurrent febrile seizures.

METHODS

A retrospective analysis was performed on the medical data and examination results of 34 children with recurrent febrile seizures who underwent two magnetic resonance plain scans of the head and the hippocampus from January 1, 2013 to September 30, 2019. According to the follow-up time, they were divided into the first follow-up group and the second follow-up group. According to prognosis, they were divided into a febrile seizure group, a non-febrile group and an epilepsy group. The change in HCV was analyzed and compared.

RESULTS

Total HCV was positively correlated with age (r_s=0.683, P < 0.05). The second follow-up group had a significantly larger total HCV than the first follow-up group (P < 0.05). For both groups, preschool children (≥ 3 years old) had significantly larger total HCV, left HCV, and right HCV than those at an age of < 3 years (P < 0.05). For both groups, the children with persistent seizures had significantly lower average annual increment (ΔV) of total HCV, left HCV, and right HCV than those without persistent seizures (P < 0.05). There was no significant difference in ΔV of total HCV, left HCV, and right HCV among the febrile seizure, non-febrile seizure and epilepsy groups (P > 0.05).

CONCLUSIONS

HCV gradually increases with age in children with recurrent febrile seizures. Persistent seizures may damage the development of the hippocampus.

Refractory and Super-refractory Status Epilepticus

Context

Refractory status epilepticus (RSE) and super-refractory status epilepticus (SRSE) are neurological emergencies with considerable mortality and morbidity. In this paper, we provide an overview of causes, evaluation, treatment, and consequences of RSE and SRSE, reflecting the lack of high-quality evidence to inform therapeutic approach.

Sources

This is a narrative review based on personal practice and experience. Nevertheless, we searched MEDLINE (using PubMed and OvidSP vendors) and Cochrane central register of controlled trials, using appropriate keywords to incorporate recent evidence.

Results

Refractory status epilepticus is commonly defined as an acute convulsive seizure that fails to respond to two or more anti-seizure medications including at least one nonbenzodiazepine drug. Super-refractory status epilepticus is a status epilepticus that continues for ≥24 hours despite anesthetic treatment, or recurs on an attempted wean of the anesthetic regimen. Both can occur in patients known to have epilepsy or de novo, with increasing recognition of autoimmune and genetic causes. Electroencephalography monitoring is essential to monitor treatment response in refractory/super-refractory status epilepticus, and to diagnose non-convulsive status epilepticus. The mainstay of treatment for these disorders includes anesthetic infusions, primarily midazolam, ketamine, and pentobarbital. Dietary, immunological, and surgical treatments are viable in selected patients. Management is challenging due to multiple acute complications and long-term adverse consequences.

Conclusions

We have provided a synopsis of best practices for diagnosis and management of refractory/superrefractory status epilepticus and highlighted the lack of sufficient high-quality evidence to drive decision making, ending with a brief foray into avenues for future research.

High genetic burden in 163 Chinese children with status epilepticus

PURPOSE

This study aimed to investigate the genetic aetiology in Chinese children diagnosed with status epilepticus (SE).

METHODS

Next-generation sequencing, copy number variation (CNV) analysis, and other genetic testing methods were conducted for children with SE lacking an identifiable non-genetic aetiology. Furthermore, the phenotype and molecular data of patients with SE were retrospectively analysed.

RESULTS

Among children with SE lacking an identifiable non-genetic aetiology, 73 out of 163 children (44.8 %) were found to have causative variants associated with SE including 66 monogenic mutations in 22 genes and 7 CNVs. Based on the American College of Medical Genetics and Genomics scoring system, the monogenic variants included 64 pathogenic/likely pathogenic and 2 uncertain significance variants. SCN1A gene mutations (n = 32) were the most common cause, followed by TSC2 (n = 5), CACNA1A (n = 5), SCN2A (n = 4), SCN9A (n = 2) and DEPDC5 (n = 2) gene mutations. Sixteen mutations were identified in single genes. Furthermore, 51 (77.3 %) monogenic mutations were de novo. Age at SE onset < 1 year (odds ratio [OR] = 2.70, 95 % confidence interval [CI]: 1.25-5.83, p = 0.012) and co-morbidity of intellectual disability (OR = 3.36, 95 %CI: 1.61-6.99, p = 0.001) were independently associated with pathogenic genetic variants.

CONCLUSION

This study identified genetic aetiology in 44.8 % of patients with SE, which indicates a high burden of genetic aetiology among children with SE in China. Our findings highlight the importance for genetic testing of children with SE that lacks an identifiable non-genetic aetiology.

Genetic Contributions to Acquired Epilepsies

Whether genetic factors contribute to acquired epilepsies has long been controversial. Supporters observe that, among individuals exposed to seemingly the same brain insult, only a minority develops unprovoked seizures. Yet, only in relatively recent years have studies started to build a case for genetic contributions. Here, we appraise this emerging evidence, by providing a critical review of studies published in the field.

Sex-Dependent Signaling Pathways Underlying Seizure Susceptibility and the Role of Chloride Cotransporters

Seizure incidence, severity, and antiseizure medication (ASM) efficacy varies between males and females. Differences in sex-dependent signaling pathways that determine network excitability may be responsible. The identification and validation of sex-dependent molecular mechanisms that influence seizure susceptibility is an emerging focus of neuroscience research. The electroneutral cation-chloride cotransporters (CCCs) of the SLC12A gene family utilize Na⁺-K⁺-ATPase generated electrochemical gradients to transport chloride into or out of neurons. CCCs regulate neuronal chloride gradients, cell volume, and have a strong influence over the electrical response to the inhibitory neurotransmitter GABA. Acquired or genetic causes of CCCs dysfunction have been linked to seizures during early postnatal development, epileptogenesis, and refractoriness to ASMs. A growing number of studies suggest that the developmental expression of CCCs, such as KCC2, is sex-dependent. This review will summarize the reports of sexual dimorphism in epileptology while focusing on the role of chloride cotransporters and their associated modulators that can influence seizure susceptibility.

Risk Factors of Febrile Status Epilepticus

OBJECTIVE

We aimed to investigate the risk factors of febrile status epilepticus (FSE) in children.

MATERIALS & METHODS

This analytic case-control study was conducted on all patients' records with first febrile seizure (FS) admitted to 17 Shahrivar Hospital, Rasht, Iran during 2007-2014. Cases were children aged 6 to 60 months with FSE and controls were children with complex and simple FS. Data were gathered using a checklist including age, sex, type of milk consuming during first year, temperature, the interval between fever and seizure, family history of epilepsy and febrile seizure, and prematurity. Data were analyzed using Chi-square in SPSS 19.

RESULTS

Overall, 756 patients with FS participated including 39 patients with FSE, 194 complex febrile seizure (CFC) and 523 simple febrile seizure (SFC). Most of the patients (57.8%) experienced seizure with low-grade fever (<39 °C). The mean age in SFC group was significantly higher than FSE patients (P<0.05). A significant relation was noted between groups regarding body temperature during seizure (P=0.006), family history of FS (0.029), family history of epilepsy (P=0.042) and the premature birth (P=0.023). Significant relation was noted between FSE and CFC groups regarding body temperature during seizure (P=0.004), family history of FS (0.011), family history of epilepsy (P=0.037), and the premature birth (P=0.025) between FSE and CFC groups.

CONCLUSION

Considering risk factors of FSE including low body temperature, lower age, family history of FS and epilepsy, and premature birth is mandatory.

Plasma cytokines associated with febrile status epilepticus in children: A potential biomarker for acute hippocampal injury

OBJECTIVE

Our aim was to explore the association between plasma cytokines and febrile status epilepticus (FSE) in children, as well as their potential as biomarkers of acute hippocampal injury.

METHODS

Analysis was performed on residual samples of children with FSE (n = 33) as part of the Consequences of Prolonged Febrile Seizures in Childhood study (FEBSTAT) and compared to children with fever (n = 17). Magnetic resonance imaging (MRI) was obtained as part of FEBSTAT within 72 h of FSE. Cytokine levels and ratios of antiinflammatory versus proinflammatory cytokines in children with and without hippocampal T2 hyperintensity were assessed as biomarkers of acute hippocampal injury after FSE.

RESULTS

Levels of interleukin (IL)-8 and epidermal growth factor (EGF) were significantly elevated after FSE in comparison to controls. IL-1β levels trended higher and IL-1RA trended lower following FSE, but did not reach statistical significance. Children with FSE were found to have significantly lower ratios of IL-1RA/IL-1β and IL-1RA/IL-8. Specific levels of any one individual cytokine were not associated with FSE. However, lower ratios of IL-1RA/IL-1β, IL-1RA/1L-6, and IL-1RA/ IL-8 were all associated with FSE. IL-6 and IL-8 levels were significantly higher and ratios of IL-1RA/IL-6 and IL-1RA/IL-8 were significantly lower in children with T2 hippocampal hyperintensity on MRI after FSE in comparison to those without hippocampal signal abnormalities. Neither individual cytokine levels nor ratios of IL-1RA/IL-1β or IL-1RA/IL-8 were predictive of MRI changes. However, a lower ratio of IL-1RA/IL-6 was strongly predictive (odds ratio [OR] 21.5, 95% confidence interval [CI] 1.17-393) of hippocampal T2 hyperintensity after FSE.

SIGNIFICANCE

Our data support involvement of the IL-1 cytokine system, IL-6, and IL-8 in FSE in children. The identification of the IL-1RA/IL-6 ratio as a potential biomarker of acute hippocampal injury following FSE is the most significant finding. If replicated in another study, the IL-1RA/IL-6 ratio could represent a serologic biomarker that offers rapid identification of patients at risk for ultimately developing mesial temporal lobe epilepsy (MTLE).

Quantitative Evaluation of Medial Temporal Lobe Morphology in Children with Febrile Status Epilepticus: Results of the FEBSTAT Study

BACKGROUND AND PURPOSE

The pathogenesis of febrile status epilepticus is poorly understood, but prior studies have suggested an association with temporal lobe abnormalities, including hippocampal malrotation. We used a quantitative morphometric method to assess the association between temporal lobe morphology and febrile status epilepticus.

MATERIALS AND METHODS

Brain MR imaging was performed in children presenting with febrile status epilepticus and control subjects as part of the Consequences of Prolonged Febrile Seizures in Childhood study. Medial temporal lobe morphologic parameters were measured manually, including the distance of the hippocampus from the midline, hippocampal height:width ratio, hippocampal angle, collateral sulcus angle, and width of the temporal horn.

RESULTS

Temporal lobe morphologic parameters were correlated with the presence of visual hippocampal malrotation; the strongest association was with left temporal horn width (P < .001; adjusted OR, 10.59). Multiple morphologic parameters correlated with febrile status epilepticus, encompassing both the right and left sides. This association was statistically strongest in the right temporal lobe, whereas hippocampal malrotation was almost exclusively left-sided in this cohort. The association between temporal lobe measurements and febrile status epilepticus persisted when the analysis was restricted to cases with visually normal imaging findings without hippocampal malrotation or other visually apparent abnormalities.

CONCLUSIONS

Several component morphologic features of hippocampal malrotation are independently associated with febrile status epilepticus, even when complete hippocampal malrotation is absent. Unexpectedly, this association predominantly involves the right temporal lobe. These findings suggest that a spectrum of bilateral temporal lobe anomalies are associated with febrile status epilepticus in children. Hippocampal malrotation may represent a visually apparent subset of this spectrum.

Risk factors for subsequent febrile seizures in the FEBSTAT study

OBJECTIVES

To identify risk and risk factors for developing a subsequent febrile seizure (FS) in children with a first febrile status epilepticus (FSE) compared to a first simple febrile seizure (SFS). To identify home use of rescue medications for subsequent FS.

METHODS

Cases included a first FS that was FSE drawn from FEBSTAT and Columbia cohorts. Controls were a first SFS. Cases and controls were classified according to established FEBSTAT protocols. Cumulative risk for subsequent FS over a 5-year period was compared in FSE versus SFS, and Cox proportional hazards regression was conducted. Separate analysis examined subsequent FS within FSE. The use of rescue medications at home was assessed for subsequent FS.

RESULTS

Risk for a subsequent FSE was significantly increased in FSE versus SFS. Any magnetic resonance imaging (MRI) abnormality increased the risk 3.4-fold (p < 0.05), adjusting for age at first FS and FSE and in analyses restricted to children whose first FS was FSE (any MRI abnormality hazard ratio [HR] 2.9, p < 0.05). The risk for a second FS of any type or of subsequent FS lasting >10 min over the 5-year follow-up did not differ in FSE versus SFS. Rectal diazepam was administered at home to 5 (23.8%) of 21 children with subsequent FS lasting ≥10 min.

SIGNIFICANCE

Compared to controls, FSE was associated with an increased risk for subsequent FSE, suggesting the propensity of children with an initial prolonged seizure to experience a prolonged recurrence. Any baseline MRI abnormality increased the recurrence risk when FSE was compared to SFS and when FSE was studied alone. A minority of children with a subsequent FS lasting 10 min or longer were treated with rectal diazepam at home, despite receiving prescriptions after the first FSE. This indicates the need to further improve the education of clinicians and parents in order to prevent subsequent FSE.

Evaluation of Risk Factors Associated with First Episode Febrile Seizure

INTRODUCTION

Febrile seizure (FS) is the single most common type of seizure seen in children between 6 months to 5 years of age. The purpose of our study was to identify the risk factors associated with the first episode of febrile seizures, which would help in the better management and preventive measures in children at risk for FS episodes.

AIM

To evaluate the risk factors associated with the first episode of febrile seizures in Indian children.

MATERIALS AND METHODS

This was a hospital based, case control study. The purpose of this study was to identify the risk factors associated with the first FS episode in children. Seventy (70) children between age 6 months to 5 years with their first episode of FS were compared with 70 children with fever but without seizures based on various risk factors.

RESULTS

The mean age was 24.90±16.11 months in cases and 26.34±16.93 months in controls. Male: female ratio was 2:1. A positive family history was found in 31.4% of first degree and 11.4% in second degree relatives. Mean maximum temperature was 102.06±1.1°F and URI (upper respiratory infection) was most common cause of fever. Antenatal complication was significantly higher in the case group. RBC (Red Blood Cells) indices like lower mean haemoglobin, MCV (Mean Corpuscular Volume), MCH (Mean Corpuscular Haemoglobin concentration) and higher RDW (Red Cell Distribution Width) values were seen in patients. Serum sodium, Serum calcium and random blood sugar values of the cases were significantly lower than those of controls (p<0.05).

CONCLUSION

Our study shows that male gender, family history of febrile seizures, peak body temperature, underlying cause of fever, antenatal complications, low serum calcium, sodium, blood sugar and microcytic hypochromic anaemia are the risk factors associated with the occurrence of first episode of febrile seizure and, thus, preventive measures in removing these risk factors could lead to a decrease in incidence of FS.

Febrile Seizures and Febrile Seizure Syndromes: An Updated Overview of Old and Current Knowledge

Febrile seizures are the most common paroxysmal episode during childhood, affecting up to one in 10 children. They are a major cause of emergency facility visits and a source of family distress and anxiety. Their etiology and pathophysiological pathways are being understood better over time; however, there is still more to learn. Genetic predisposition is thought to be a major contributor. Febrile seizures have been historically classified as benign; however, many emerging febrile seizure syndromes behave differently. The way in which human knowledge has evolved over the years in regard to febrile seizures has not been dealt with in depth in the current literature, up to our current knowledge. This review serves as a documentary of how scientists have explored febrile seizures, elaborating on the journey of knowledge as far as etiology, clinical features, approach, and treatment strategies are concerned. Although this review cannot cover all clinical aspects related to febrile seizures at the textbook level, we believe it can function as a quick summary of the past and current sources of knowledge for all varieties of febrile seizure types and syndromes.

Summary of recommendations for the management of infantile seizures: Task Force Report for the ILAE Commission of Pediatrics

Evidence-based guidelines, or recommendations, for the management of infants with seizures are lacking. A Task Force of the Commission of Pediatrics developed a consensus document addressing diagnostic markers, management interventions, and outcome measures for infants with seizures. Levels of evidence to support recommendations and statements were assessed using the American Academy of Neurology Guidelines and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The report contains recommendations for different levels of care, noting which would be regarded as standard care, compared to optimal care, or "state of the art" interventions. The incidence of epilepsy in the infantile period is the highest of all age groups (strong evidence), with epileptic spasms the largest single subgroup and, in the first 2 years of life, febrile seizures are the most commonly occurring seizures. Acute intervention at the time of a febrile seizure does not alter the risk for subsequent epilepsy (class 1 evidence). The use of antipyretic agents does not alter the recurrence rate (class 1 evidence), and there is no evidence to support initiation of regular antiepileptic drugs for simple febrile seizures (class 1 evidence). Infants with abnormal movements whose routine electroencephalography (EEG) study is not diagnostic, would benefit from video-EEG analysis, or home video to capture events (expert opinion, level U recommendation). Neuroimaging is recommended at all levels of care for infants presenting with epilepsy, with magnetic resonance imaging (MRI) recommended as the standard investigation at tertiary level (level A recommendation). Genetic screening should not be undertaken at primary or secondary level care (expert opinion). Standard care should permit genetic counseling by trained personal at all levels of care (expert opinion). Genetic evaluation for Dravet syndrome, and other infantile-onset epileptic encephalopathies, should be available in tertiary care (weak evidence, level C recommendation). Patients should be referred from primary or secondary to tertiary level care after failure of one antiepileptic drug (standard care) and optimal care equates to referral of all infants after presentation with a seizure (expert opinion, level U evidence). Infants with recurrent seizures warrant urgent assessment for initiation of antiepileptic drugs (expert opinion, level U recommendation). Infantile encephalopathies should have rapid introduction and increment of antiepileptic drug dosage (expert opinion, level U recommendation). There is no high level evidence to support any particular current agents for use in infants with seizures. For focal seizures, levetiracetam is effective (strong evidence); for generalized seizures, weak evidence supports levetiracetam, valproate, lamotrigine, topiramate, and clobazam; for Dravet syndrome, strong evidence supports that stiripentol is effective (in combination with valproate and clobazam), whereas weak evidence supports that topiramate, zonisamide, valproate, bromide, and the ketogenic diet are possibly effective; and for Ohtahara syndrome, there is weak evidence that most antiepileptic drugs are poorly effective. For epileptic spasms, clinical suspicion remains central to the diagnosis and is supported by EEG, which ideally is prolonged (level C recommendation). Adrenocorticotropic hormone (ACTH) is preferred for short-term control of epileptic spasms (level B recommendation), oral steroids are probably effective in short-term control of spasms (level C recommendation), and a shorter interval from the onset of spasms to treatment initiation may improve long-term neurodevelopmental outcome (level C recommendation). The ketogenic diet is the treatment of choice for epilepsy related to glucose transporter 1 deficiency syndrome and pyruvate dehydrogenase deficiency (expert opinion, level U recommendation). The identification of patients as potential candidates for epilepsy surgery should be part of standard practice at primary and secondary level care. Tertiary care facilities with experience in epilepsy surgery should undertake the screening for epilepsy surgical candidates (level U recommendation). There is insufficient evidence to conclude if there is benefit from vagus nerve stimulation (level U recommendation). The key recommendations are summarized into an executive summary. The full report is available as Supporting Information. This report provides a comprehensive foundation of an approach to infants with seizures, while identifying where there are inadequate data to support recommended practice, and where further data collection is needed to address these deficits.

Symptomatic neonatal seizures followed by febrile status epilepticus: the two-hit hypothesis for the subsequent development of epilepsy

Neonatal seizures have been associated with the later development of postneonatal epilepsy, mainly beginning within the first year of life. Mechanisms of epileptogenesis in the immature brain still need to be fully elucidated but a two-hit hypothesis, showing that an early insult heightens later susceptibility to seizure-induced brain damage, has been demonstrated in animal models. We describe 2 cases of preterm babies sustaining recurrent neonatal seizures in the context of a severe perinatal brain damage who presented with symptomatic epilepsy only after the occurrence of an episode of febrile status epilepticus. In the context of preexisting perinatal brain damage, febrile status epilepticus acted as a second hit for developing epilepsy, confirming animal evidence.

Actual insights into the clinical management of febrile seizures

Febrile seizures (FS) are a benign epileptic manifestation of infancy occurring between 3 months and 5 years of age and affecting an estimated 2-5 % of children. They have usually no important negative effects on motor and cognitive development. Simple FS (generalized seizures, lasting less than 10 min and single episodes during the same febrile event) have a benign prognosis in almost all cases and do not require an extensive diagnostic workup. In complex FS (focal semiology and lasting more than 10 min, more than one episode during the same febrile event), a more detailed clinical, electroencephalographic, laboratory, and neuroimaging evaluation is necessary because of a higher percentage of underlying detectable causes and a mildly higher risk for later development of epilepsy. Febrile status epilepticus is the most severe type of complex FS even if its morbidity and mortality is extremely low. Simple FS plus (more than one convulsive episode in 24 h) have the same benign prognosis of simple FS. Neither intermittent nor continuous prophylaxis is actually recommended both in simple and complex FS because its side effects outweigh its possible benefits.

CONCLUSION

This review summarizes recent developments into the clinical management of FS including a suggested algorithm for simple and complex FS, the concept of simple FS plus, the controversies about the relationships between FS and hippocampal sclerosis, the relationships between FS and complex syndrome such as Dravet syndrome, genetic epilepsy with FS plus or febrile infection-related epilepsy syndrome, and the results of recent epidemiologic studies on febrile status epilepticus.

Sex-specific consequences of early life seizures

Seizures are very common in the early periods of life and are often associated with poor neurologic outcome in humans. Animal studies have provided evidence that early life seizures may disrupt neuronal differentiation and connectivity, signaling pathways, and the function of various neuronal networks. There is growing experimental evidence that many signaling pathways, like GABAA receptor signaling, the cellular physiology and differentiation, or the functional maturation of certain brain regions, including those involved in seizure control, mature differently in males and females. However, most experimental studies of early life seizures have not directly investigated the importance of sex on the consequences of early life seizures. The sexual dimorphism of the developing brain raises the question that early seizures could have distinct effects in immature females and males that are subjected to seizures. We will first discuss the evidence for sex-specific features of the developing brain that could be involved in modifying the susceptibility and consequences of early life seizures. We will then review how sex-related biological factors could modify the age-specific consequences of induced seizures in the immature animals. These include signaling pathways (e.g., GABAA receptors), steroid hormones, growth factors. Overall, there are very few studies that have specifically addressed seizure outcomes in developing animals as a function of sex. The available literature indicates that a variety of outcomes (histopathological, behavioral, molecular, epileptogenesis) may be affected in a sex-, age-, region-specific manner after seizures during development. Obtaining a better understanding for the gender-related mechanisms underlying epileptogenesis and seizure comorbidities will be necessary to develop better gender and age appropriate therapies.

The challenges and innovations for therapy in children with epilepsy

Major advances have been made in the diagnosis, evaluation and management of children with epilepsy over the past 15 years. There has been a marked increase in genetic diagnoses of a number of key childhood-onset epilepsy syndromes, such as Dravet syndrome, which has been linked to mutations in the SCN1A gene. The reorganization and reclassification of epilepsies, devised by the International League Against Epilepsy, has stimulated specialists to reassess their diagnostic practices; however, many studies have not addressed the global issues in treating children with epilepsy-specifically, the challenges of diagnosis through to optimal, and appropriate, therapeutic management. Also, Class I evidence-based data that are needed as a foundation for the development of treatment guidelines worldwide are lacking. Epilepsy is common, and the impact of this disease crosses age ranges and should be managed at all levels of care from community to quaternary care. In this Review, existing data and new therapeutic management approaches are discussed with the aim of highlighting the incidence of standard practices that may not be based on clinical evidence.