Current understanding of febrile seizures and their long-term outcomes

Research progress on pathogenesis and treatment of febrile seizures

Febrile seizures (FSs) are the most common pediatric neurological disorder, affecting approximately 5 % of children aged 6 months to 5 years. While most FSs are self-limiting and benign, about 20-30 % present as complex FSs (CFSs), which pose a risk of acute brain injury and the development of temporal lobe epilepsy. Various factors, including age, geographical distribution, and type of infection influence the occurrence of FS. Infection is the primary external trigger for FS, while the underlying intrinsic factors are linked to the immature and incomplete myelination of the brain during specific developmental stages. Although the precise pathogenesis of FS is not yet fully understood, it is likely caused by the interaction of immature brain development, fever, neuroinflammation, and genetic susceptibility. This review discussed the pathogenesis of febrile seizures, focusing on factors such as age, fever, neuroinflammation, genetics, and intestinal microbiota, and summarized existing therapeutic approaches. Our review may facilitate the identification of new targets for mechanistic studies and clinical treatment of febrile seizures.

Stimuli-responsive nanoscale drug delivery system for epilepsy theranostics

Epilepsy is a common neurological disease characterized by distinct pathological changes in the epileptogenic zone. Antiseizure drugs (ASDs) are widely used as the primary treatment for epilepsy. To improve the efficiency of ASDs medication, stimuli-responsive nanoscale drug delivery systems (nanoDDSs), triggered by either endogenous or exogenous factors, have been developed and been considered as a noninvasive and spatial-temporal approach to epilepsy theranostics. In this review, we introduce the pathological variations observed in epileptic lesions such as dysregulated neurotransmitter systems, disrupted ion homeostasis, and dynamic inflammatory cytokine networks. Furthermore, we summarize the recent advances in functional nano-assemblies that could be activated by endogenous stimuli of pathological alterations or exogenous stimuli such as electricity, light, and other interventions. Finally, we discuss the remaining challenges and prospect the insight into perspective of future development in this field. In summary, this review aims to highlight the potential of stimuli-responsive nanoDDSs as precise, controllable and efficient strategies for addressing unresolved issues in epilepsy theranostics. STATEMENT OF SIGNIFICANCE: This review summarizes recent progress in pathological changes such as dysregulated neurotransmitter system, disrupted ion homeostasis and dynamic inflammatory cytokine network, and emphasizes endogenous/exogenous stimuli-responsive nanoscale platforms including neurotransmitter-, ion-, and other stimuli-responsive nanoDDSs, providing the prospects of smart nanoDDSs applications and discussing the challenges to offer generalized guideline for further development of epilepsy theranostics.

Identification of Reliable Reference Genes for Use in Gene Expression Studies in Rat Febrile Seizure Model

The study of the pathogenesis of febrile seizures and their consequences frequently necessitates gene expression analysis. The primary methodology employed for such analysis is reverse transcription with quantitative polymerase chain reaction (RT-qPCR). To ensure the accuracy of data obtained by RT-qPCR, it is crucial to utilize stably expressed reference genes. The objective of this study was to identify the most suitable reference genes for use in the analysis of mRNA production in various brain regions of rats following prolonged neonatal febrile seizures. The expression stability of eight housekeeping genes was evaluated using the online tool RefFinder in the dorsal and ventral hippocampal regions and in the temporal and medial prefrontal cortex of the brain. The Ppia gene exhibited the greatest stability of expression. Conversely, the genes with the least stable expression levels were Actb and Ywhaz; thus, it is not recommended to use them for normalization in a febrile seizure model. Additionally, the majority of housekeeping genes demonstrate age-related, region-specific fluctuations. Therefore, it is crucial to employ the appropriate housekeeping genes for each brain structure under investigation when examining the expression dynamics of genes of interest in a febrile seizure model.

Upregulations of high mobility group box 1 and TLR4/NF-κB signaling pathway in hippocampus and serum of rats with febrile seizure

PURPOSE

The aim of this study was to explore the alternations regarding the HMGB1 and TLR4/NF-κB signaling pathway in juvenile rats with febrile seizure (FS).

MATERIALS AND METHODS

During the animal modeling of the FS, seizures were triggered every four days by hot water (45 °C), and repeated ten times. After forty days' modeling, rats were divided into different groups according to the degree of seizure (FS (0) - FS (V)). Reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate the mRNA expressions of the HMGB1, TLR4 and NF-κB in the hippocampus, while Western-blot (WB) and immunofluorescence (IF) were employed to assess protein expressions. The enzyme-linked immunosorbent assay (ELISA) was used for analyzing the protein expressions in peripheral blood.

RESULTS

The mRNA levels of the HMGB1, TLR4 and NF-κB in the hippocampus of both FS (V) and FS (IV) groups were significantly higher than WT, while there was no difference between FS (III) and WT. Concerning protein expressions, increased levels of the HMGB1, TLR4, and NF-κB in FS (V) were observed with a good consistency between the WB and IF, while no significant upregulation was shown in FS (IV). The ELISA results showed that the significance of the augmented proteins between the FS (V) and WT were smaller in the serum than the hippocampus.

CONCLUSIONS

Our study shows seizure degree-related upregulations of HMGB1 and TLR4/NF-κB signaling pathway both in hippocampus and serum of juvenile rats with FS, suggesting the involvement of TLR/NF-κB pathway in inflammation promoted by HMGB1 during FS.

Ultrastructural Analysis of the Large Neuronal Perikarya in an Injured Dentate Nucleus Using an Experimental Model of Hyperthermia-Induced Convulsions: The First Qualitative and Quantitative Study

Background: Febrile seizures are a common form of convulsions in childhood, with poorly known cellular mechanisms. The objective of this pioneering study was to provide qualitative and quantitative ultrastructural research on the large neuronal perikarya in the cerebellar dentate nucleus (DN), using an experimental model of hyperthermia-induced seizures (HSs), comparable to febrile seizures in children. Methods: The study used young male Wistar rats, divided into experimental and control groups. The HSs were evoked by a hyperthermic water bath at 45 °C for 4 min for four consecutive days. Specimens (1 mm3) collected from the DN were routinely processed for transmission electron microscopy studies. Results: The ultrastructure of the large neurons in the DN affected by hyperthermic stress showed variously pronounced lesions in the perikarya, including total cell disintegration. The most pronounced neuronal lesions exhibited specific morphological signs of aponecrosis, i.e., dark cell degeneration ('dark neurons'). In close vicinity to the 'dark neurons', the aponecrotic bodies were found. The findings of this qualitative ultrastructural study correspond with the results of the morphometric analysis of the neuronal perikarya. Conclusions: Our results may constitute interesting comparative material for similar submicroscopic observations on large DN neurons in HS morphogenesis and, in the future, may help to find potential treatment targets to prevent febrile seizures or reduce recurrent seizures in children.

Value of combining targeted emergency nursing with psychological nursing in children with febrile convulsions

BACKGROUND

Febrile convulsions are a common pediatric emergency that imposes significant psychological stress on children and their families. Targeted emergency care and psychological nursing are widely applied in clinical practice, but their value and impact on the management of pediatric febrile convulsions are unclear.

AIM

To determine the impact of targeted emergency nursing combined with psychological nursing on satisfaction in children with febrile convulsions.

METHODS

Data from 111 children with febrile convulsions who received treatment at Nantong Maternal and Child Health Care Hospital between June 2021 and October 2022 were analyzed. The control group consisted of 44 children who received conventional nursing care and the research group consisted of 67 children who received targeted emergency and psychological nursing. The time to fever resolution, time to resolution of convulsions, length of hospital stays, Pittsburgh Sleep Quality Index, patient compliance, nursing satisfaction of the parents, occurrence of complications during the nursing process, and parental anxiety and depression were compared between the control and research groups. Parental anxiety and depression were assessed using the Hamilton Rating Scale for Depression (HAMD) and the Hamilton Rating Scale for Anxiety (HAMA).

RESULTS

The fever resolution, convulsion disappearance, and hospitalization times were longer in the control group compared with the research group (P < 0.0001). The time to falling asleep, sleep time, sleep quality, sleep disturbance, sleep efficiency, and daytime status scores were significantly better in the research group compared with the control group (P < 0.0001). The HAMD and HAMA scores for parents of children in the research group were lower than the scores in the control group after nursing (P < 0.05). Compliance with treatment of children in the research group was higher than in the control group (P < 0.05). Parental satisfaction with nursing in the research group was higher than in the control group (P < 0.05). The total complication rate of children in the control group was higher than in the research group (P < 0.05).

CONCLUSION

Combining psychological nursing with targeted emergency nursing improved the satisfaction of children's families and compliance with treatment and promoted early recovery of clinical symptoms and improvement of sleep quality.

Clinical Profile and Predictors of Recurrent Simple Febrile Seizure

BACKGROUND

Recurrent simple febrile seizure (SFS) refers to febrile seizure (FS) that recurs within 24 hours. Patients with recurrent SFS often undergo unnecessary neurodiagnostic tests. To address this, we compared the clinical characteristics of recurrent SFS with those of SFS and investigated the risk factors associated with recurrent SFS.

METHODS

We retrospectively reviewed electronic medical records of patients aged six to 60 months who had been hospitalized for FS at two training hospitals between January 2016 and December 2019. The primary outcome was a comparison of the clinical features of patients with SFS and recurrent SFS. Additionally, the risk factors associated with seizure recurrence within 24 hours were evaluated.

RESULTS

Three quarters (n = 191, 75.2%) of the 254 enrolled patients experienced a single seizure episode during the febrile illness period. The remaining 63 patients (24.8%) were diagnosed with recurrent SFS. Significant differences between SFS and recurrent SFS were observed in the history of recurrent SFS, time from fever onset to seizure, and body temperature on hospital arrival. Multiple logistic regression analysis revealed that a history of previous recurrent SFS (odds ratio [OR] 10.161) and a body temperature below 39°C on arrival (OR 2.377) were significantly associated with early seizure recurrence.

CONCLUSIONS

This study highlights that early FS recurrence is common and has a self-limiting clinical course similar to that of SFS. We recommend close monitoring of the patient for six to eight hours when a history of early recurrence is present or if the seizure occurs at a low body temperature.

Characteristics and Risk Factors of Central Nervous System Infection in Children With Febrile Seizures

OBJECTIVE

The aim of the present study is to evaluate the necessity of performing lumbar puncture in patients experiencing febrile seizures, considering the epidemiology specific to Brazil.

METHODS

A retrospective cross-sectional study was performed from January 2017 to December 2021.

RESULTS

A total of 469 children with seizure and fever were analyzed. The identified event was the first in 65.9% (n = 309). A total of 54.2% (n = 254) of patients had a simple febrile seizure. Infectious focus, excluding previous central nervous system (CNS) infection, was identified in 35.6% (n = 167) patients. Meningitis was identified in 7.7% (n = 36) patients, all of them were viral. Patients with CNS infection had a higher frequency of symptoms such as nausea and vomiting, drowsiness, headache, and higher level of leukocytosis. A longer duration of fever was found to be more strongly associated with CNS infection.

CONCLUSIONS

When considering the use of lumbar puncture in febrile seizure, it is important to conduct a comprehensive evaluation that considers multiple factors, including clinical signs, symptoms, and the overall clinical context. Meningeal signs may be less prominent, and other symptoms such as lethargy, irritability, and vomiting may serve as more reliable indicators. Although clinical examination suggestive of meningitis remains an important factor, the recurrence of febrile seizures and a longer length of fever can provide additional insights and aid in decision-making regarding lumbar puncture.

Comparison of clinical characteristics and disease burden of febrile seizures in children with and without COVID-19

BACKGROUND

Febrile seizures (FS) are the most common seizure disorder in children and a common neurologic complication in children with coronavirus disease 2019 (COVID-19). This study aimed to identify differences in clinical characteristics and disease burden between FS with and without COVID-19.

MATERIALS AND METHODS

We conducted a retrospective analysis of medical data at our hospital from December 2019 to July 2023, focusing on hospitalized patients under the age of 14 diagnosed with FS who underwent COVID-19 polymerase chain reaction (PCR) testing. Descriptive statistics and analysis of variance were employed to compare the COVID-19 and non-COVID-19 groups in terms of clinical characteristics and disease burden.

RESULTS

A total of 514 patients were included, with 106 testing positive for COVID-19 and 408 testing negative. Patients with COVID-19 were older (34.87 ± 6.16 vs. 28.61 ± 11.35 months, P < 0.001) and had a higher proportion of males (79.2% vs. 62.3%, P = 0.001). The COVID-19 group had longer seizure durations (4.57 ± 4.38 vs. 3.22 ± 2.91 min, P = 0.006) and more complex FS (25.5% vs. 15.9%, P = 0.022). Laboratory tests showed lower lymphocyte counts in the COVID-19 group (1.87 ± 1.48 vs. 2.75 ± 1.51 × 103/µL, P < 0.001) and higher creatine kinase levels (158.49 ± 82.89 vs. 110.89 ± 56.11 U/L, P < 0.001). No significant differences were found in hospital costs, length of hospitalization, and intensive care unit admissions.

CONCLUSION

Clinicians should be knowledgeable about the distinct clinical characteristics of FS in children with COVID-19. Despite distinct features, the prognosis remains favorable and does not require excessive intervention. Ongoing monitoring and research are needed to fully understand the impact of COVID-19 on FS and optimize management strategies.

Higher Risk of Psychiatric Disorders in Children With Febrile Seizures: A Nationwide Cohort Study in Taiwan

BACKGROUND

Febrile seizures occur commonly in children aged between six months and six years. A previous Danish study found a positive correlation between febrile seizures and the overall incidence of psychiatric disorders. This population-based nationwide observational study was conducted to investigate the association between febrile seizures and different psychiatric disorders in Taiwan and the associated risk factors.

METHODS

This cohort study used data from the National Health Insurance Research Database in Taiwan-a nationwide claims database covering >99% of the Taiwanese population. The study period was from January 2000 to December 2015; the overall median follow-up time was 11.04 ± 10.95 years. Overall, 2464 children with febrile seizures diagnosed between 2000 and 2015 met the inclusion criteria, and 7392 children without febrile seizures matched by index year, age, and sex were included in the control cohorts. Febrile seizures and psychiatric disorders were measured as the exposure and main outcomes, respectively.

RESULTS

Children with febrile seizures (n = 2463) were at a high risk of psychiatric disorders (adjusted hazard ratio, 4.70; 95% confidence interval [CI], 2.44 to 7.30; P < 0.001). The risk for anxiety was the highest (adjusted hazard ratio, 21.92; 95% CI, 11.40 to 34.05; P < 0.001).

CONCLUSIONS

When treating children with febrile seizures, particular attention should be paid to the symptoms of psychiatric disorders, as early referral may be beneficial for these children.

The protective effect of breastfeeding on febrile seizures: a systematic review with meta-analysis

Several potential risk factors have been identified in the etiopathogenesis of febrile seizures (FS), including the type and extent of breastfeeding (BF). Given the lack of conclusive data, this study aims to systematically evaluate the evidence on the association between BF and FS. We conducted a systematic review and meta-analysis according to PRISMA guidelines. The search was conducted using descriptors for FS, BF, and formula feeding in MEDLINE, Embase, and Web of Science databases. We included observational studies that compared the incidence of FS between those who had ever breastfed and those who were formula fed. The study protocol was registered on the PROSPERO platform under the number CRD42023474906. A total of 1,893,079 participants from 8 datasets were included. Our main analysis showed no significant association of any type of BF on the incidence of FS compared with formula-fed children (OR: 0.84; CI: 0.67-1.04; I2 = 78%; Cochran's Q = 0.0001), although meta-regression showed that BF was associated with a lower incidence of FS in preterm infants. Our secondary outcome showed a significantly reduced incidence of FS in children who received BF exclusively (OR: 0.80; CI: 0.65-0.99; I2 = 70%; Cochran's Q = 0.02).    Conclusion: There was no significant reduction in the incidence of FS in those who were breastfed compared to formula feeding. However, our meta-regression analysis indicated an association between BF and a lower incidence of FS in preterm infants. Additionally, children who exclusively received BF had a significantly reduced incidence of FS. These findings should be further investigated in prospective cohorts. What is Known: • Breastfeeding can modify risk factors for febrile seizures, such as susceptibility to viral and bacterial infections, micronutrient deficiencies, and low birth weight. • However, studies have shown conflicting results regarding the impact of breastfeeding on febrile seizures. What is New: • When comparing any breastfeeding pattern with no breastfeeding, there is no significant difference in the incidence of febrile seizures. • When comparing exclusive breastfeeding with no breastfeeding, there may be a decrease in the occurrence of febrile seizures.

Additive interaction between birth asphyxia and febrile seizures on autism spectrum disorder: a population-based study

BACKGROUND

Autism Spectrum Disorder (ASD) is a pervasive neurodevelopmental disorder that can significantly impact an individual's ability to socially integrate and adapt. It's crucial to identify key factors associated with ASD. Recent studies link both birth asphyxia (BA) and febrile seizures (FS) separately to higher ASD prevalence. However, investigations into the interplay of BA and FS and its relationship with ASD are yet to be conducted. The present study mainly focuses on exploring the interactive effect between BA and FS in the context of ASD.

METHODS

Utilizing a multi-stage stratified cluster sampling, we initially recruited 84,934 Shanghai children aged 3-12 years old from June 2014 to June 2015, ultimately including 74,251 post-exclusion criteria. A logistic regression model was conducted to estimate the interaction effect after controlling for pertinent covariates. The attributable proportion (AP), the relative excess risk due to interaction (RERI), the synergy index (SI), and multiplicative-scale interaction were computed to determine the interaction effect.

RESULTS

Among a total of 74,251 children, 192 (0.26%) were diagnosed with ASD. The adjusted odds ratio for ASD in children with BA alone was 3.82 (95% confidence interval [CI] 2.42-6.02), for FS alone 3.06 (95%CI 1.48-6.31), and for comorbid BA and FS 21.18 (95%CI 9.10-49.30), versus children without BA or FS. The additive interaction between BA and FS showed statistical significance (P < 0.001), whereas the multiplicative interaction was statistically insignificant (P > 0.05).

LIMITATIONS

This study can only demonstrate the relationship between the interaction of BA and FS with ASD but cannot prove causation. Animal brain experimentation is necessary to unravel its neural mechanisms. A larger sample size, ongoing monitoring, and detailed FS classification are needed for confirming BA-FS interaction in ASD.

CONCLUSION

In this extensive cross-sectional study, both BA and FS were significantly linked to ASD. The coexistence of these factors was associated with an additive increase in ASD prevalence, surpassing the cumulative risk of each individual factor.

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.

Identification of two novel and one rare mutation in DYRK1A and prenatal diagnoses in three Chinese families with intellectual Disability-7

Background and purpose: Intellectual disability-7 (MRD7) is a subtype disorder of intellectual disability (MRD) involving feeding difficulties, hypoactivity, and febrile seizures at an age of early onset, then progressive intellectual and physical development deterioration. We purposed to identify the underlying causative genetic factors of three individuals in each Chinese family who presented with symptoms of intellectual disability and facial dysmorphic features. We provided prenatal diagnosis for the three families and genetic counseling for the prevention of this disease. Methods: We collected retrospective clinical diagnostic evidence for the three probands in our study, which included magnetic resonance imaging (MRI), computerized tomography (CT), electroencephalogram (EEG), and intelligence tests for the three probands in our study. Genetic investigation of the probands and their next of kin was performed by Trio-whole exome sequencing (WES). Sanger sequencing or quantitative PCR technologies were then used as the next step to verify the variants confirmed with Trio-WES for the three families. Moreover, we performed amniocentesis to explore the state of the three pathogenic variants in the fetuses by prenatal molecular genetic diagnosis at an appropriate gestational period for the three families. Results: The three probands and one fetus were clinically diagnosed with microcephaly and exhibited intellectual developmental disability, postnatal feeding difficulties, and facial dysmorphic features. Combining probands' clinical manifestations, Trio-WES uncovered the three heterozygous variants in DYRK1A: a novel variant exon3_exon4del p.(Gly4_Asn109del), a novel variant c.1159C>T p.(Gln387*), and a previously presented but rare pathogenic variant c.1309C>T p.(Arg437*) (NM_001396.5) in three families, respectively. In light of the updated American College of Medical Genetic and Genomics (ACMG) criterion, the variant of exon3_exon4del and c.1159C>T were both classified as likely pathogenic (PSV1+PM6), while c1309C>T was identified as pathogenic (PVS1+PS2_Moderate+PM2). Considering clinical features and molecular testimony, the three probands were confirmed diagnosed with MRD7. These three discovered variants were considered as the three causal mutations for MRD7. Prenatal diagnosis detected the heterozygous dominant variant of c.1159C>T p.(Gln387*) in one of the fetuses, indicating a significant probability of MRD7, subsequently the gestation was intervened by the parents' determination and professional obstetrical operation. On the other side, prenatal molecular genetic testing revealed wild-type alleles in the other two fetuses, and their parents both decided to sustain the gestation. Conclusion: We identified two novel and one rare mutation in DYRK1A which has broadened the spectrum of DYRK1A and provided evidence for the diagnosis of MRD7 at the molecular level. Besides, this study has supported the three families with MRD7 to determine the causative genetic factors efficiently and provide concise genetic counseling for the three families by using Trio-WES technology.

Clinical features of febrile seizures in children with COVID-19: an observational study from a tertiary care hospital in China

Background

Febrile seizures are a common neurologic manifestation in children with coronavirus disease 2019 (COVID-19). Compared to seasonal respiratory viruses, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a pronounced neurological impact, with the result that febrile seizures with COVID-19 may exhibit unique clinical features.

Materials and methods

We conducted a retrospective study in a tertiary care hospital in China. We collected medical record information on febrile seizures with COVID-19, including demographic characteristics, clinical features, laboratory tests, and disease burden. Subsequently, the data were then analyzed descriptively.

Results

A total of 103 children diagnosed with febrile seizures and positive COVID-19 PCR results were included in our study. Among them, 81 (78.6%) were males and 22 (21.4%) were females. The age of onset of febrile seizures ranged from 14 to 57 months, with a mean age of 34.9 ± 6.24 months. Complex febrile seizures were observed in 34 (33%) cases. Antiseizure medications were administered to 24 (23.3%) patients. Laboratory tests showed a white blood cell count of (27.05 ± 8.20) × 103/µl, a neutrophil count of (20.09 ± 5.66) × 103/µl and a lymphocyte count of (6.44 ± 1.86) × 103/µl. A creatine kinase level was significantly elevated, with a mean value of (412.00 ± 158.96) U/L. The mean length of stay was 4.36 days. Twelve patients (11.7%) required intensive care services, but there were no deaths or patients remaining on antiseizure medications after discharge.

Conclusion

In the post-epidemic era of COVID-19, pediatric clinicians should be aware of the changing clinical features of febrile seizures associated with COVID-19. The average age of onset has increased, with a higher proportion of males. Length of stay and hospitalization costs did not increase significantly. The prognosis remained favorable, although a small number of children required intensive care services during the acute phase.

Febrile Seizures

Febrile seizures (FSs) are the most common cause of pediatric seizures. They are defined as seizures in children age 6 months to 5 years with a temperature higher than 100.4°F, although they are more common at higher temperatures. A family history of FS is the most common risk factor. FSs are classified into three types (simple, complex, or febrile status epilepticus) based on duration and quality, with simple FSs accounting for many cases. Most FSs persist for less than 10 minutes and are self-limiting. Approximately one-third of patients will have recurrence of FSs. Safe and effective prophylaxis for FS has yet to be identified. Most patients will not have any long-term sequelae, although there is an increased risk of epilepsy, particularly for those with febrile status epilepticus. FSs are associated with caregiver anxiety, "fever phobia," and high health care use, emphasizing the importance of education and reassurance for both the provider and family. [Pediatr Ann. 2023;52(10):e388-e393.].

Are brief febrile seizures benign? A systematic review and narrative synthesis

Febrile seizures affect 2%-5% of U.S. children and are considered benign although associated with an increased risk of epilepsy and, rarely, with sudden unexplained death. We compared rates of mortality, neurodevelopmental disorders, and neuropathology in young children with simple and complex febrile seizures to healthy controls. We systematically reviewed studies of 3- to 72-month-old children with simple or complex febrile seizures ≤30 min. We searched studies with outcome measures on mortality, neurodevelopment, or neuropathology through July 18, 2022. Bias risk was assessed per study design. Each outcome measure was stratified by study design. PROSPERO registration is CRD42022361645. Twenty-six studies met criteria reporting mortality (11), neurodevelopment (11), and neuropathology (13), including 2665 children with febrile seizures and 1206 seizure-free controls. Study designs varied: 15 cohort, 2 cross-sectional, 3 case-control, 5 series, and 1 case report. Mortality outcomes showed stark contrasts. Six cohort studies following children after febrile seizure (n = 1348) reported no deaths, whereas four child death series and 1 case report identified 24.1% (108/449) deaths associated with simple (n = 104) and complex (n = 3) febrile seizures ≤30 min. Minor hippocampal histopathological anomalies were common in sudden deaths with or without febrile seizure history. Most electroencephalography (EEG) studies were normal. Neuroimaging studies suggested increased right hippocampal volumes. When present, neurodevelopmental problems usually preexisted febrile-seizure onset. Risk bias was medium or high in 95% (18/19) of cohort and case-control studies vs medium to low across remaining study designs. Research on outcomes after simple or brief complex febrile seizures is limited. Cohort studies suffered from inadequate sample size, bias risk, and limited follow-up durations to make valid conclusions on mortality, neurodevelopment, and neuropathology. Sudden death registries, focused on a very small percentage of all cases, strongly suggest that simple febrile seizures are associated with increased mortality. Although most children with febrile seizures have favorable outcomes, longer-term prospective studies are needed.

Comprehensive Evaluation of Inflammatory Biomarkers and Osmolarity to Distinguish Simple and Complex Febrile Seizures in Children

With limited sample sizes and varying study outcomes regarding complete blood count (CBC)-associated biomarkers and their febrile seizure (FS) classification, along with limited research on osmolarity, this study aims to evaluate CBC-associated biomarkers, including osmolarity, for a comprehensive view of their diagnostic value. This single-center retrospective study used data from 364 children (aged 5-60 months) diagnosed with FS. The patients were categorized into simple FS (n = 221) and complex FS (n = 143) groups. CBC and biochemical tests, including sodium, potassium, chloride, glucose, blood urea nitrogen, and C-reactive protein levels, were evaluated. The neutrophil-to-lymphocyte ratio (NLR), mean platelet volume-to-lymphocyte ratio, and osmolarity were calculated and compared between FS types and the number of seizures. Receiver operating characteristic (ROC) curve analysis was conducted to assess the predictive utility of these markers. Inflammatory markers, including NLR, were ineffective in predicting FS types. Complex FS cases exhibited a significantly lower osmolarity than simple FS cases. The area under the ROC curve for osmolarity to distinguish complex FS was 0.754, while other markers did not reach the desired threshold of 0.700. Including osmolarity in the classification of FS has clinical applicability. Physicians may consider osmolarity as an additional tool to aid in clinical decision-making.

Febrile Seizures Cause a Rapid Depletion of Calcium-Permeable AMPA Receptors at the Synapses of Principal Neurons in the Entorhinal Cortex and Hippocampus of the Rat

Febrile seizures (FSs) are a relatively common early-life condition that can cause CNS developmental disorders, but the specific mechanisms of action of FS are poorly understood. In this work, we used hyperthermia-induced FS in 10-day-old rats. We demonstrated that the efficiency of glutamatergic synaptic transmission decreased rapidly after FS by recording local field potentials. This effect was transient, and after two days there were no differences between control and post-FS groups. During early ontogeny, the proportion of calcium-permeable (CP)-AMPA receptors in the synapses of the principal cortical and hippocampal neurons is high. Therefore, rapid internalization of CP-AMPA receptors may be one of the mechanisms underlying this phenomenon. Using the whole-cell patch-clamp method and the selective CP-AMPA receptor blocker IEM-1460, we tested whether the proportion of CP-AMPA receptors changed. We have demonstrated that FS rapidly reduces synaptic CP-AMPA receptors in both the hippocampus and the entorhinal cortex. This process was accompanied by a sharp decrease in the calcium permeability of the membrane of principal neurons, which we revealed in experiments with kainate-induced cobalt uptake. Our experiments show that FSs cause rapid changes in the function of the glutamatergic system, which may have compensatory effects that prevent excessive excitotoxicity and neuronal death.

Jujuboside B inhibits febrile seizure by modulating AMPA receptor activity

ETHNOPHARMACOLOGICAL RELEVANCE

Febrile seizure is a common neurologic disorder with limited treatment occurring in infants and children under the age of five. Jujuboside B (JuB) is a main bioactive saponin component isolated from the Chinese anti-insomnia herbal medicine Ziziphi Spinosae Semen (ZSS), seed of Ziziphus jujuba Mill, which has been proved to exhibit neuroprotective effects recently.

AIM OF THE STUDY

In this study, we aimed at elucidating the effect of JuB on suppressing febrile seizure and the potential mechanisms.

METHODS

Electroencephalogram (EEG) recording was used to monitor the severity of febrile seizures. The JuB in the brain was identified by mass spectrometry. Neuronal excitability was investigated using patch clamp.

RESULTS

JuB (30 mg/kg) significantly prolonged seizure latency and reduced the severity in hyperthermia-induced seizures model mice. Hippocampal neuronal excitability was significantly decreased by JuB. And JuB significantly reduced the excitatory synaptic transmission mediated by α-amino-3-hydroxy-5-methyl-4-iso-xazolepropionic acid receptor (AMPAR), including evoked excitatory postsynaptic currents (eEPSCs), and miniature EPSCs (mEPSCs) in hippocampal neurons. Furthermore, JuB also significantly inhibited recombinant GluA1 and GluA2 mediated AMPA current in HEK293 cell and decreased the upregulation of [Ca²⁺]_i induced by AMPA in primary cultured cortex neurons.

CONCLUSIONS

JuB suppressed the excitability of hippocampal neurons by inhibiting the activity of AMPAR and reducing the intracellular free calcium, thereby relieving febrile seizures.

Inflammation as a target for the treatment of fever-associated epilepsy in zebrafish larvae

Inflammation is considered to be involved in epileptogenesis. However, the relationship between fever and inflammation as well as the mechanisms of fever in the occurrence and development of childhood epilepsy need further investigation. Here, we described an in vivo model of hyperthermia-induced seizures in zebrafish larvae with pentylenetetrazole (PTZ) exposure. Hyperthermia increased the susceptibility to seizure and the production of pro-inflammatory factors in PTZ-induced zebrafish larvae. As mutations in GABRG2 have been associated with fever-associated epilepsy, we used a Tg(hGABRG2^F343L) zebrafish model expressing mutant human GABRG2(F343L) to further investigate the involvement of inflammation in fever-induced seizures. Our data indicated that hyperthermia also increased the locomotor activity in Tg(hGABRG2^F343L) zebrafish larvae. Although the production of pro-inflammatory factors was upregulated by GABRG2 mutation, hyperthermia did not change the production of pro-inflammatory factors significantly. Lipopolysaccharide (LPS) stimulation was sufficient to increase the locomotor activity in zebrafish larvae, suggesting that inflammation contributed to fever-associated epilepsy. The expression of GABRG2 was increased with PTZ induction, especially at a higher temperature. Moreover, inhibition of inflammation by dexamethasone (DEX) reduced the excitability of zebrafish larvae, especially at a higher temperature. Finally, in vitro experiments proved that LPS stimulation increased the production of IL-1β and IL-6 in GABRG2(F343L) transfected cells. Collectively, our study demonstrated that neuroinflammation was induced in febrile seizures, and the increased expression of IL-1β and IL-6 might be responsible for epileptogenesis. The vicious cycle between fever and inflammation might induce seizure onset, and anti-inflammatory strategies might be a potential treatment for fever-associated epilepsy.

Effect of nursing interventions based on the Kano model on symptom relief and parental psychological behavior in children with febrile seizures

Purpose

To analyze the effect of nursing interventions based on the Kano model on symptom relief and parental psychological behavior in children with febrile seizures (FS).

Methods

A total of 104 children with FS and their corresponding families admitted to our hospital from January 2021 to April 2022 as the research object. All children were divided into 2 groups according to their nursing regimen during treatment. Children who received general nursing interventions were enrolled in the general group (n = 52) and children who received nursing interventions based on the Kano model were enrolled in the Kano group (n = 52). In this study, an investigation was first conducted to analyze the attributes of the caring care service needs of the families of children with FS. Then, we compared 4 aspects of symptom relief during the hospital stay of the 2 groups of children, including FS seizure frequency, time to cessation of convulsions, time to recovery of consciousness and time to fever reduction. The parent symptom questionnaire (PSQ) was used to assess the psychological behavior of the two groups of children during the hospital stay. The Chinese perceived stress scale (CPSS) and the symptom checklist 90 (SCL-90) were used to assess the psychological behavior of the two groups of their families during the children's hospitalization. Finally, a questionnaire was administered on the satisfaction of this nursing intervention.

Results

In terms of symptom relief, the children in the Kano group had less frequent of FS seizure than the general group, and the time to cessation of convulsions, time to recovery of consciousness and time to fever reduction were all earlier than in the genera group (p < 0.05). In terms of children's psychological behavior, the impulsivity-hyperactivity, anxiety, hyperactivity index and learning problems scores in the PSQ of the children in the Kano group were lower than those in the general group after the intervention (p < 0.05). In terms of family psychological behavior, the psychological behavioral problems of the families of the children in both groups improved after the intervention, and the CPSS scores of tension and dis-control, as well as the total SCL-90 score of the families of the children in the Kano group were lower than those of the general group (p < 0.05). In terms of family satisfaction, the Kano group was significantly better than the general group (p < 0.05).

Conclusion

The implementation of the nursing interventions based on the Kano model for children with FS was successful in dramatically reducing the clinical signs and symptoms of the children and meeting the psychological and behavioral needs of the children and their families.

Combined measles-mumps-rubella-varicella vaccine and febrile convulsions: the risk considered in the broad context

INTRODUCTION

Studies on quadrivalent measles, mumps, rubella, and varicella (MMRV) vaccines have indicated a twofold increased relative risk of febrile convulsion (FC) after the first dose compared to MMR and V administered at the same medical visit (MMR+V).

AREAS COVERED

This narrative review contextualizes FC occurrence after the first MMRV vaccine dose from a clinical perspective and outlines approaches to attenuate FC occurrence post-vaccination.

EXPERT OPINION

While the relative FC risk increases after the first dose of MMRV compared to MMR+V vaccine in measles-naïve infants, the attributable risk is low versus the overall FC risk in the pediatric population triggered by other causes, like natural exposure to pathogens or routine vaccination. No increased risk of FC has been reported after MMRV co-administration with other routine vaccines compared to MMRV alone. Based on our findings and considering the MMRV vaccination benefits (fewer injections, higher coverage, better vaccination compliance), the overall benefit-risk profile of MMRV vaccine is considered to remain positive. Potential occurrence of FC in predisposed children (e.g. with personal/family history of FC) may be attenuated if they receive MMR+V instead of MMRV as the first dose. It is also important to monitor vaccinees for fever during the first 2 weeks post-vaccination.

MRI Abnormalities of the Brain After Complex Febrile Seizures in Children

Background Though simple febrile seizures do not cause significant and lasting neurological deficits, complex febrile seizures (CFS) can result in neurologic sequelae. Because CFS causes cortical focal injuries and other brain lesions, it needs to be evaluated. Objective The objective of this study was to evaluate the MRI brain changes in CFS, the incidence of seizures in children aged six months to five years, and their severity in relation to MRI findings of the brain. Methods In this observational study, 36 children aged six months to five years, having fever with seizure, and fulfilling the criteria of CFS were enrolled within 48 hours of the episode. Detailed clinical and neurological examinations were performed with MRI scans to find out the probable CNS lesions of CFS. Two radiologists separately evaluated all MRI brains. Results MRI lesions of the brain were found in 11 (30.56%) CFS patients. Generalized tonic-clonic seizures (GTCS) (n=31, 86.11%) were the most common type of seizure among CFS cases. Cortical focal hyperintensity (CFH) (42.1%) was the most common MRI presentation. Positive MRI findings were significantly associated with focal convulsions (n=5, 100%) as compared to GTCS cases (n=6, 19%) (p=0.001). Conclusions CFH is the most common abnormality in the MRI brain among CFS cases. CFS patients with focal seizures or prolonged seizures in 24 hours have higher abnormal neuroimaging findings. MRI should be considered a preferred investigatory tool for detecting CNS pathology in CFS cases. Follow-up studies are needed to determine the long-term outcomes of CNS lesions in children with CFS.

Acute dizziness and mental alteration associated with Moderna COVID-19 vaccine: a case report

Background

Due to a rising number of COVID-19 cases, the Indonesian government implemented public health programs to lower the rate. Since January 2021, one of the government’s primary policies has been the COVID-19 immunization program. Recently, the Moderna messenger ribonucleic acid (mRNA) vaccine is one of the COVID-19 vaccines used in Indonesia. Based on some research, Moderna has possible side effects throughout the body, including neurological symptoms.

Case presentation

We describe a 39-year-old female with uncontrolled hypertension who showed behavioral change, communication difficulty, social withdrawal, and a confused state within 7 days from getting her first dose of the Moderna vaccine. The patient had a history of febrile convulsion in childhood. An increase of neutrophil-to-lymphocyte ratio (16.9) and C-reactive protein level (31.75 mg/L) indicates ongoing inflammation. Head CT scan shows no abnormalities. She received ceftriaxone, citicoline, and methylprednisolone. The patient was discharged on the seventh day and completely recovered 1 week later. This study is the first case report of encephalopathy following the administration of the Moderna COVID-19 vaccine reported in Indonesia up to our knowledge.

Conclusion

Encephalopathy related to the Moderna COVID-19 vaccine should be acknowledged as an adverse effect of the Moderna COVID-19 vaccine.

Neuroplastic alterations in cannabinoid receptors type 1 (CB1) in animal models of epileptic seizures

Currently, there is an urgent need to better comprehend neuroplastic alterations in cannabinoid receptors type 1 (CB1) and to understand the biological meaning of these alterations in epileptic disorders. The present study reviewed neuroplastic changes in CB1 distribution, expression, and functionality in animal models of epileptic seizures. Neuroplastic alterations in CB1 were consistently observed in chemical, genetic, electrical, and febrile seizure models. Most studies assessed changes in hippocampal and cortical CB1, while thalamic, hypothalamic, and brainstem nuclei were rarely investigated. Additionally, the relationship between CB1 alteration and the control of brain excitability through modulation of specific neuronal networks, such as striatonigral, nigrotectal and thalamocortical pathways, and inhibitory projections to hippocampal pyramidal neurons, were all presented and discussed in the present review. Neuroplastic alterations in CB1 detected in animal models of epilepsy may reflect two different scenarios: (1) endogenous adaptations aimed to control neuronal hyperexcitability in epilepsy or (2) pathological alterations that facilitate neuronal hyperexcitability. Additionally, a better comprehension of neuroplastic and functional alterations in CB1 can improve pharmacological therapies for epilepsies and their comorbidities.

Growth charts of brain morphometry for preschool children

Brain development from 1 to 6 years of age anchors a wide range of functional capabilities and carries early signs of neurodevelopmental disorders. However, quantitative models for depicting brain morphology changes and making individualized inferences are lacking, preventing the identification of early brain atypicality during this period. With a total sample size of 285, we characterized the age-dependence of the cortical thickness and subcortical volume in neurologically normal children and constructed quantitative growth charts of all brain regions for preschool children. While the cortical thickness of most brain regions decreased with age, the entorhinal and parahippocampal regions displayed an inverted-U shape of age-dependence. Compared to the cortical thickness, the normalized volume of subcortical regions exhibited more divergent trends, with some regions increasing, some decreasing, and some displaying inverted-U-shaped trends. The growth curve models for all brain regions demonstrated utilities in identifying brain atypicality. The percentile measures derived from the growth curves facilitate the identification of children with developmental speech and language disorders with an accuracy of 0.875 (area under the receiver operating characteristic curve: 0.943). Our results fill the knowledge gap in brain morphometrics in a critical development period and provide an avenue for individualized brain developmental status evaluation with demonstrated sensitivity.

Seizures and Epilepsy in Childhood

PURPOSE OF REVIEW

This article highlights basic concepts of seizures and epilepsy in pediatric patients, as well as basic treatment principles for this age group.

RECENT FINDINGS

Epilepsy is the most common neurologic disorder in childhood. Accurate diagnosis is key; in older children, epileptic seizures need to be differentiated from various paroxysmal nonepileptic events, whereas in neonates, the majority of seizures are subclinical (electroencephalographic). Antiseizure medications remain the first-line treatment, but ketogenic diet and epilepsy surgery have also shown positive outcomes and can decrease drug burden. Genetic causes account for approximately 30% of cases, and the recognition of electroclinical syndromes is being replaced by the concept of genetic spectrums. Precision medicine therapies are promising, but wide application in daily practice still has a long way to go. Early access to specialist centers and optimal treatments positively affects prognosis and future neurodevelopment.

SUMMARY

Although novel findings from all fields of research are being incorporated into everyday clinical practice, a better quality of life for children with seizures and epilepsy and their families is the ultimate priority.

Longitudinal neurodevelopmental profile of a pediatric patient with de novo SPTAN1, epilepsy, and left hippocampal sclerosis

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We present the first longitudinal study of neuropsychological functioning in a pediatric patient with SPTAN1.

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To our knowledge we report the first case of SPTAN1 heterozygosity in a patient with MTLE due to HS.

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This case is the first to show that lisdexamfetamine dimesylate improved attention, behavior, and school performance in a patient with heterozygous SPTAN1 variant.

Pathogenic variants in SPTAN1 result in abnormal neurodevelopment but limited information is available on the spectrum of neurodevelopmental profiles associated with variations in this gene. We present novel data collected at two time points over a three-year period in a nine-year-old patient with heterozygous de novo SPTAN1 variant, drug-resistant epilepsy, and left hippocampal sclerosis. Across evaluations, our patient’s performance was highly variable, ranging from below age expectation to within age-expected range. The patient exhibited relative cognitive strengths at both time points on verbal-expressive tasks. Weaknesses were seen in her attention, executive function, psychomotor processing speed, fine motor, visual-motor integration, and social skills. Memory findings were consistent those associated with left hippocampal sclerosis. Evaluations resulted in diagnoses including attention deficit hyperactivity disorder and autism spectrum disorder.

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.

Early Life Febrile Seizures Impair Hippocampal Synaptic Plasticity in Young Rats

Febrile seizures (FSs) in early life are significant risk factors of neurological disorders and cognitive impairment in later life. However, existing data about the impact of FSs on the developing brain are conflicting. We aimed to investigate morphological and functional changes in the hippocampus of young rats exposed to hyperthermia-induced seizures at postnatal day 10. We found that FSs led to a slight morphological disturbance. The cell numbers decreased by 10% in the CA1 and hilus but did not reduce in the CA3 or dentate gyrus areas. In contrast, functional impairments were robust. Long-term potentiation (LTP) in CA3-CA1 synapses was strongly reduced, which we attribute to the insufficient activity of N-methyl-D-aspartate receptors (NMDARs). Using whole-cell recordings, we found higher desensitization of NMDAR currents in the FS group. Since the desensitization of NMDARs depends on subunit composition, we analyzed NMDAR current decays and gene expression of subunits, which revealed no differences between control and FS rats. We suggest that an increased desensitization is due to insufficient activation of the glycine site of NMDARs, as the application of D-serine, the glycine site agonist, allows the restoration of LTP to a control value. Our results reveal a new molecular mechanism of FS impact on the developing brain.

Hyperthermia-induced seizures during neonatal period alter the functionality of A1 and A2A receptors in the cerebellum and evoke fine motor impairment and gait disturbances in adult rats

Febrile seizures (FS) are one of the most common types of convulsive disorder of early childhood and they can be classified into simple and prolonged depending on the duration. Nowadays, simple FS have a good prognosis but there is controversy about the outcome of prolonged FS. In a previous work using an animal model of prolonged FS, we showed that hiperthermia-induced seizures (HIS) evoked fine motor coordination impairment and gait disturbances in adolescent rats in a process in which seemed to be involved modulation of the cerebellar adenosinergic system. The aim of the present work was to verify whether the effect was maintained in adulthood. To this end, neonatal rats (PD 12) were exposed to HIS and after 48 days (PD 60) they were assayed on balance beam and footprint tests. Animals were sacrificed 53 days after HIS and adenosine A₁ and A_2A receptor signalling pathways were studied in cerebellar plasma membranes by using radioligand binding assays and by measuring the activities of 5´-nucleotidase and adenylyl cyclase. Results obtained revealed that adult rats exposed to HIS showed gait disturbances and motor impairments. Besides, animals exposed to hyperthermic insult showed an increase in adenosine A_2A receptor functionality and 5´-nucleotidase activity. Surprisingly, the functionality of the adenosine A₁ receptor resulted significantly changed causing stimulation instead of inhibition of adenylate cyclase activity. These results showed that the effect of prolonged FS at the early age also persist in adulthood suggesting on must pay attention to FS in children.

Seizures Related to Influenza in Pediatric Patients: A Comparison with Seizures Associated with Other Respiratory Viral Infections

Although febrile seizures are the most common neurological complications of influenza, there are few studies comparing seizure characteristics and outcomes between patients with influenza and those with other respiratory virus (RV) infections. Medical records of pediatric patients presenting with seizures accompanied by fever, in whom RV infections were identified, were retrospectively reviewed to compare the characteristics and outcomes of seizures with fever due to influenza (n = 97) to those due to other RV infections (n = 113). Patients with influenza were older than those with other RV infections (p < 0.001), and 22.7% of them were aged ≥5 years. Seizure characteristics of complex febrile seizures were observed more frequently in patients with other RV infections than in those with influenza; however, the frequency of epilepsy was comparable between the two groups. For patients with influenza, children aged <5 years and those aged ≥5 years showed similar seizure characteristics and outcomes. Further neurological evaluations should not be based solely on patient age in children with influenza who experience late-onset seizures at ≥5 years of age. Long-term sequelae should be further investigated in these patients.