Respiratory viruses and febrile response in children with febrile seizures: A cohort study and embedded case-control study

Occurrence of Central Nervous System Complications of Respiratory Syncytial Virus Infections: A Systematic Review with Meta-Analysis

An increasing base of evidence suggests that respiratory syncytial virus (RSV) infections may be associated with neurological complications. In accord with the PRISMA statement, we performed a systematic review and meta-analysis on the occurrence of encephalitis and encephalopathy associated with documented RSV infections. PubMed, Embase, and Scopus databases were searched for eligible observational studies published up to 10 April 2024. Raw data included the occurrence of RSV infections among cases of encephalitis and/or encephalopathy and cases of encephalitis and/or encephalopathy among series of RSV infections. Data were pooled in a random effects model. Case reports were also collected, and their data pooled as a cumulative series. Heterogeneity was assessed using the I2 measure, while reporting bias was assessed by means of funnel plots and regression analysis. A total of 15 studies for a total of 7719 RSV infections and 1631 cases of encephalitis were analyzed. Moreover, 27 case reports and case series were retrieved, for a total of 84 individual cases of encephalitis/encephalopathy occurring during a documented RSV infection. A pooled prevalence of 2.20 cases of encephalitis/encephalopathy per 100 RSV cases (I2 = 99%) was calculated, while a prevalence of RSV infections among cases of encephalitis/encephalopathy was estimated to 3.53 per 100 cases for studies on respiratory specimens (I2 = 48%) and 0.37 per cases on central nervous system (CNS) specimens (I2 = 0%). Detection of RSV within the CNS was relatively rare (17.86% of pooled case reports), being associated with male gender (adjusted odds ratio [aOR] 5.021, 95% confidence interval [95%CI] 1.104 to 22.831) and recovery with long-term sequelae (aOR 5.699, 95%CI 1.152; 28.183). Case fatality ratio was estimated to be 0.43 per 100 cases on observational studies and 10.71% in case reports, a difference likely due to publication bias. In summary, RSV represented a not frequent but notable cause of encephalitis/encephalopathy in adults and children. The paucity of available studies not only recommends a cautious appraisal of our results but stresses the clinical significance of future studies on incident cases of encephalitis and/or encephalopathy.

Decreased NK cell count is a high-risk factor for convulsion in children with COVID-19

BACKGROUND

The neurological symptoms caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are of increasing concern. Convulsions are among the main neurological manifestations reported in children with coronavirus disease-2019 (COVID-19), and cause serious harm to physical and mental health. This study aimed to investigate the risk factors for convulsion in children with COVID-19.

METHODS

This prospective study was conducted at the Children's Hospital of Soochow University. In total, 102 COVID-19 patients with convulsion, 172 COVID-19 patients without convulsion, and 50 healthy controls were enrolled in the study. The children's clinical and laboratory data were analyzed to assess the risk factors for convulsion in COVID-19 patients.

RESULTS

Convulsions occurred in 37.2% of children, mostly those aged 1-3 years, who were hospitalized with the Omicron variant. The neutrophil count, neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), and mean platelet volume-to-platelet ratio (MPR) were significantly higher in the convulsion group than those in the non-convulsion and control groups (P < 0.01). However, the counts of lymphocytes, eosinophils, platelets, lymphocyte subsets, CD3+ T cells, CD4+ T cells, CD8+ T cells, and NK cells were lower in the convulsion group than those in the non-convulsion and control groups (P < 0.01). Multivariate regression analysis indicated that NK cell count (OR = 0.081, 95% CI: 0.010-0.652) and a history of febrile seizure (OR = 10.359, 95% CI: 2.115-50.746) were independent risk factors for the appearance of convulsions in COVID-19.

CONCLUSIONS

History of febrile seizure and decreased NK cell count were high-risk factors for convulsions in COVID-19 patients.

Comparison of neurological manifestation in children with and without coronavirus 2019 experiencing seizures with fever

Whether neurologic symptoms due to SARS-CoV-2 differ from those of non-SARS-CoV-2 viral infection is unclear. We aimed to describe these neurological manifestations and compare the clinical characteristics and treatments in children with seizures and fever with or without COVID-19. We retrospectively analyzed data from 105 hospitalized children (<18 years) with clinical seizures and fever between September 2021 and August 2022. We compared the clinical characteristics and treatments between the COVID-19 (n = 20) and non-COVID-19 (n = 85) groups. Patients with COVID-19 were older than those without (32.5 [20-86] months vs. 20 [16-32] months, p = 0.029). Seizure type and duration and impaired consciousness duration did not differ between groups. Six and 32 patients experienced status epilepticus lasting 30 min in the COVID-19 and non-COVID-19 groups, respectively. Most treatments did not differ between groups; however, electroencephalography was used less frequently for COVID-19. Neurological sequelae occurred in one and four patients in the COVID-19 and non-COVID-19 groups, respectively. In conclusion, seizures with fever due to SARS-CoV-2 were more common in older children. Seizure characteristics and neurologic sequelae did not differ in children with and those without COVID-19. In general, electroencephalography was used less during COVID-19 for infection control measures.

A Prospective Observational Study of Children with FS-Associated Hospitalization: The Implication and Outcomes of Pathogen Detection in Cerebrospinal Fluid

Background

Febrile seizures (FS) are a common cause of paediatric emergencies, but research on their aetiology and epidemiology are limited. The aim of this study was to investigate the prevalence of central nervous system (CNS) pathogenic infections in patients with FS-associated hospitalization.

Methods

A prospective observational study was conducted in children under 16 years of age with FS-associated hospitalization. Demographic, clinical and laboratory data were recorded. Multiplex-PCR was performed on cerebrospinal fluid (CSF) samples for nine viruses, nine bacteria and one fungus.

Results

A total of 119 children were enrolled between June 2021 and June 2022. Of these, 83.2% had a final diagnosis of FS (69.7%) or FS plus (13.4%). In addition, epilepsy and encephalitis/meningitis were also found in 16.8% (20/119). Seven pathogens were identified from 9 CSF samples (7.6%), including viruses (EV, EBV, HHV-6) and bacteria (H. influenzae, S. pneumoniae, M. tuberculosis, S. putrefaciens). There were no significant clinical or laboratory differences between children who tested positive or negative for pathogens in the CSF, except for the presentation of herpes pharyngitis. Children with encephalitis/meningitis had longer hospital stays compared with those diagnosed with FS at discharge; abnormal EEG findings were significantly more common in patients with epilepsy.

Conclusion

FS-associated hospitalized children may have viral or bacterial intracranial infections. Pathogen testing of CSF is an important basis for timely antibiotic or antiviral therapy when clinical and laboratory findings make FS indistinguishable from other CNS disorders.

Recurrent febrile seizures and serum cytokines: a controlled follow-up study

BACKGROUND

The role of cytokines in the pathogenesis of febrile seizures (FSs) is unclear, and information regarding cytokine production outside of FS episodes is scarce.

METHODS

In our controlled follow-up study of patients with FSs, we compared the levels of 12 serum cytokines after the patients' first FSs, during febrile episodes without FSs, after recurrent FSs, during healthy periods after FSs, and between patients and controls.

RESULTS

Two-hundred fifty-one patients with first FS participated in the study, of whom 17 (mean age 1.6 years, SD 0.7) with recurrent FSs completed the protocol as required by the sample size calculations. The mean IL-1RA level was higher after the first FSs (2580 pg/mL, SD 1516) than during febrile episodes without FSs (1336 pg/mL, SD 1364, P = 0.006) and healthy periods after FSs (474 pg/mL, SD 901, P = 0.001). IL-1RA levels were also higher during first (2580 pg/mL) and recurrent FSs (2666 pg/mL, SD 1747) in comparison with febrile controls (746 pg/mL, SD 551) (P < 0.001 and P = 0.001, respectively), but there was no difference in the IL-1RA between febrile episodes without FSs and febrile controls.

CONCLUSIONS

Patients with FSs produce stronger inflammatory reactions during febrile episodes with FSs compared with febrile episodes without FSs and febrile controls.

IMPACT

In patients with FSs, IL-1RA was higher following first FS than during febrile episodes without FSs and healthy periods after FSs. IL-1RA was higher in patients with FSs following first and recurrent FSs than in febrile controls. There was no significant difference in IL-1RA between febrile episodes of patients without FSs and febrile controls. Using IL-1RA as a surrogate marker of IL-1 axis activity, our results indicate that patients with FSs produced stronger inflammatory reactions during FS episodes but not during other febrile episodes or healthy periods after FSs. Cytokines may play a role in pathogenesis of FSs.

Pathogenetic and etiologic considerations of febrile seizures

Febrile seizure (FS), which occurs in febrile children without underlying health problems, is the most common type of seizure disorder in children. The suggested pathogenesis of FS derived from several animal and human studies is multifactorial and debatable. Neuronal hyperexcitability, which develops during inflammatory responses that accompany fever, provokes seizures. However, the exact role of each inflammatory mediator (e.g., cytokines) is undefined in terms of the connection between systemic or local inflammation and the central nervous system, and the mechanisms by which cytokines increase neuronal excitability remain unclear. In contrast, the cause of fever in most children with FS is usually mild respiratory virus infection (e.g., rhinovirus, influenza virus, adenovirus, and enterovirus) rather than severe bacterial infections. In temperate regions, the major causative respiratory viruses seem to mirror seasonally prevalent respiratory viruses in the community. Therefore, vigorous efforts to identify the causative pathogen of fever may not be necessary in children with FS. Genetic factors seem to play a role in neuronal hyperexcitability, and some types of genetic variation have been identified in several genes encoding ion channels of neurons that participate in neuronal excitation. Although most children with FS have benign outcomes, some characteristics such as complex FS, febrile status epilepticus, consecutive afebrile seizures, and the presence of neurodevelopmental disabilities may require further genetic and neurologic evaluations.

Seizures in Children with SARS-CoV-2 Infection: Epidemiological, Clinical and Neurophysiological Characterization

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may present with a wide variety of symptoms, including neurological manifestations. We investigated clinical, demographic, laboratory, neurophysiological and imaging characteristics of SARS-CoV-2-positive children with seizures and analyzed differences between children admitted during the periods with prevalent circulation of the Alpha/Delta and Omicron variants, respectively. Patients' characteristics were analyzed according to the presence or absence of seizures and then according to the SARS-CoV-2 variants. Five-hundred and four SARS-CoV-2-positive patients were included: 93 (18.4%) with seizures and 411 (81.6%) without. Patients with seizures were older, had more commonly an underlying epilepsy and had more frequently altered C-reactive protein than those without seizures. Electroencephalography was abnormal in 5/38 cases. According to the SARS-CoV-2 variant, seizures were recorded in 4.7% of the total number of hospitalized patients during the Alpha/Delta period, and in 16.9% of patients admitted during the Omicron period. During the Alpha/Delta variants, seizures were more commonly observed in patients with epilepsy compared to those observed during the Omicron period. Our findings suggest that although SARS-CoV-2 may potentially trigger seizures, they are generally not severe and do not require intensive care admission.

Change in Seizure Incidence in Febrile Children With COVID-19 in the Era of Omicron Variant of Concern

In this single-center retrospective observational study, we report that the incidence of seizures in febrile children with COVID-19 was significantly higher in the Omicron era than in the pre-Omicron era (14.6% vs 1.7%, P < .001). One-third of the cases in the Omicron era were older than 5 years.

Cerebral blood flow abnormalities with central sparing on arterial spin labeling in mild encephalopathy associated with excitotoxicity: a case report

BACKGROUND

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) and mild encephalopathy associated with excitotoxicity (MEEX) are the most frequent acute encephalopathies in pediatric patients in Japan. AESD typically presents with biphasic seizures and delayed reduced diffusion in the subcortical area, called bright tree appearance (BTA), on radiological examination. In patients with AESD, arterial spin labeling (ASL) shows decreased cerebral blood flow (CBF) in the hyperacute stage and increased CBF in the acute stage, suggesting the usefulness of ASL for the early diagnosis of AESD. Additionally, proton magnetic resonance spectroscopy (MRS) shows elevated glutamate (Glu) and glutamine (Gln) in AESD. MEEX is a group of mild encephalopathies with transient elevation of Gln on MRS similar to that in AESD; however, MEEX does not include any clinical biphasic course or abnormalities, including BTA on diffusion-weighted imaging. Although the usefulness of ASL for AESD has been reported, there are no reports for patients with MEEX. In this study, we report our experience with a 4-year-old girl diagnosed with MEEX who showed unique findings on ASL.

CASE PRESENTATION

The patient was a 4-year-old girl admitted to the emergency room with febrile status epilepticus. Considering the possibility of AESD, vitamin therapy was initiated. ASL-MR imaging (MRI) of the brain performed on the second day showed increased blood flow in the frontal, temporal, and occipital regions with spared central sulcus, which indicated AESD with central sparing. The patient was diagnosed with AESD, and the treatment included pulse steroid therapy and immunoglobulin therapy from day 3. The patient remained mildly unconscious but gradually became conscious by day 7 with no seizures. Brain MRI performed on day 8 did not show any characteristic AESD findings, such as BTA. Furthermore, MRS showed elevated Gln, which, along with the clinical course, led to the diagnosis of MEEX. The patient was discharged on day 16 without obvious sequelae.

CONCLUSIONS

ASL may be useful in the early diagnosis of MEEX as well as AESD, facilitating early intervention.

Respiratory Syncytial Virus: An Uncommon Cause of Febrile Seizures-Results from a Systematic Review and Meta-Analysis

Human Respiratory Syncytial Virus (RSV) is a highly contagious viral pathogen. In infants, it is usually listed among the main causes of medical referrals and hospitalizations, particularly among newborns, and a considerable base of evidence associates RSV infections and bronchiolitis with long-term neurological sequelae. We specifically performed a systematic review and meta-analysis in order to ascertain whether RSV infections may be associated with an increased risk for febrile seizures (FS) in infected infants. According to the PRISMA statement, Pubmed, Embase, and pre-print archive medRxiv.og were searched for eligible observational studies published up to 1 July 2022. Raw data included the incidence of FS among children admitted for influenza-like illness (ILI) and/or bronchiolitis, with a confirmed diagnosis of RSV or seasonal influenza virus (SIV) infection. Data were then pooled in a random-effects model. Heterogeneity was assessed using the I² measure, while reporting bias was assessed by means of funnel plots and regression analysis. A total of 11 studies including 6847 cases of RSV infections were retrieved, with a pooled prevalence of 29.975 cases of FS per 1000 RSV cases (I² = 88.5%). The prevalence was not substantially greater in studies performed in pediatric intensive care units (53.817 per 1000 RSV cases vs. 23.552, p = 0.12). Higher occurrence of FS was reported from studies performed after 2010 (Risk Ratio [RR] 1.429, 95% Confidence Interval [95%CI] 1.049-1.948), and in China (RR 2.105, 95%CI 1.356-3.266) and South Africa (RR 1.722, 95%CI 1.060-2.824) than in Europe, while a lower occurrence was reported form the USA (RR 0.414, 95%CI 0.265-0.649). Eventually, FS were less likely reported from RSV cases compared to subjects affected by seasonal influenza (RR 0.402; 95%CI 0.228-0.708). Although RSV is often associated with high risk of neurological complications, substantially less cases of FS are reported than in SIV infections. However, the paucity of available studies recommends a cautious appraisal of aforementioned results.

Febrile seizures: perceptions and knowledge of parents of affected and unaffected children

Febrile seizures (FS) in children are common, but little is known about parents' perceptions and knowledge of FS. We interviewed parents of children aged 6 months to 6 years affected by FS (FS group, 65 parents) or unaffected (control group, 54 parents). In the FS group, 32% said they knew their child had an FS when the first event occurred, and 89% described fear when the child had a seizure, with a median intensity of 10/10 (Q25/Q75: 9/10). Related to follow-up, 77% in the FS group (will) observe their child more carefully after the first seizure happened, and 63% (will) give antipyretics earlier at a median temperature of 38.2 °C (100.8 °F). In the FS group, 62% were unaware of FS before the first event (54% of control group did not know about FS thus far, n.s.). In the FS group, 20% would put a solid object in the mouth of a child having a seizure (control group, 39%, p = 0.030), and 92% would administer an available anti-seizure rescue medication (control group, 78%, p = 0.019). In the FS group, 71% feared that children with FS might suffocate (control group, 70%, n.s.).

CONCLUSION

Information about FS and their management should be more available to improve parents' coping and patient safety.

WHAT IS KNOWN

• Febrile seizures in children are common. • The prognosis of children suffering from febrile seizures is usually rather good.

WHAT IS NEW

• Over half of parents had not informed themselves about febrile seizures so far; and only 32% of parents realized their child had a febrile seizure when it occurred. • Most parents described own fear with a median intensity of 10/10; and 63% (will) give antipyretics earlier at a median temperature of 38.2 °C (100.8 °F).

Seizures as the main presenting manifestation of acute SARS-CoV-2 infection in children

Objectives

To explore the rate, characteristics, risk factors, and prognosis of children presenting with seizures as the main symptom of acute COVID-19 (coronavirus disease 2019).

Methods

We conducted a systematic retrospective study to identify all children who presented to the emergency departments of a tertiary academic medical center between March 1st and December 31st 2020 and had a SARS-CoV-2 infection based on RT-PCR (reverse transcription-polymerase chain reaction) from nasopharyngeal swab. Clinical and demographic data were extracted from the electronic medical records and reviewed.

Results

Total of 175 children were diagnosed with acute SARS-CoV-2 infection in the emergency departments during the study period. Of those, 11 presented with seizures. Age ranged from six months to 17 years and 4 were girls. Five presented with status epilepticus and responded to loading doses of anti-seizure medications. Six had fever. Seven had prior history of neurological disorder. Full recovery was the rule.

Significance

Unlike in adults, seizures occur early and may be the main manifestation of acute COVID-19 in children. Seizures, including status epilepticus, may occur without fever even in children with no history of epilepsy and are not associated with severe disease. A high index of suspicion is required for early diagnosis thus infection control measures can be taken.