Methods of investigation and management of infections causing febrile seizures

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.

Snotwatch: an ecological analysis of the relationship between febrile seizures and respiratory virus activity

Background

Febrile seizures are the commonest type of seizure in occurring in the first few years of life, mostly affecting children aged six months to five years old. While largely benign, the incidence of each febrile seizure increases the risk of recurrence, afebrile seizures and epilepsy. Viruses are the most frequent cause of febrile illnesses in which a febrile seizure occurs. Febrile seizure presentation patterns appear to follow a seasonal trend.

Aims

To identify patterns of febrile seizure incidence across different seasons with specific viral activity, and to establish a framework for analysing virus circulation data with common illnesses within a shared region and population.

Setting

Our study was a study of febrile seizure presentations in Victoria, Australia and respiratory virus detection.

Participants

We obtained independent datasets of emergency department febrile seizure presentations at Monash Health and all respiratory multiplex PCR tests performed at Monash Health from January 2010–December 2019 to observe common trends in virus circulation and febrile seizure incidence.

Study design

Trends were studied temporally through mixed effects Poisson regression analysis of the monthly incidence of febrile seizures and the rate of positive PCR tests. Peak viral seasons (95th centile incidence) were compared to median viral circulation (50th centile incidence) to calculate peak season risk ratios.

Results

We found a 1.75–2.06 annual risk ratio of febrile seizure incidence in June–September. Temporal analysis of our data showed this peak in febrile seizures was attributable to circulating viruses in this season, and virus modelling showed correlation with increased rates of positive Influenza A (1.48 peak season risk ratio), Influenza B (1.31 peak season risk ratio), Human metapneumovirus (1.19 peak season risk ratio) and Respiratory Syncytial Virus (1.53 peak season risk ratio) on PCR testing.

Conclusion

Our ecological study statistically demonstrates the recognised winter peak in febrile seizure incidence and ascribes the seasonal relationship to several viral infections which affect the community, including a novel association with Human metapneumovirus.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03222-4.

A Review of Febrile Seizures: Recent Advances in Understanding of Febrile Seizure Pathophysiology and Commonly Implicated Viral Triggers

Febrile seizures are one of the commonest presentations in young children, with a 2-5% incidence in Western countries. Though they are generally benign, with rare long-term sequelae, there is much to be learned about their pathophysiology and risk factors. Febrile seizures are propagated by a variety of genetic and environmental factors, including viruses and vaccines. These factors must be taken into consideration by a clinician aiming to assess, diagnose and treat a child presenting with fevers and seizures, as well as to explain the sequelae of the febrile seizures to the concerned parents of the child. Our article provides an overview of this common childhood condition, outlining both the underlying mechanisms and the appropriate clinical approach to a child presenting with febrile seizures.

Profile and clinical characterization of seizures in hospitalized children

INTRODUCTION

Seizure is the commonest pediatric neurological disorder, which is frightening to caretakers. The current study aims to determine profile, clinical spectrum and analyze the commonest etiology of seizures in children admitted to a tertiary hospital in Central China.

METHODS

This was a hospital based retrospective study carried out in Zhongnan Hospital of Wuhan University, China. Computerized data was collected from January 2012 to May 2015. Variables collected were demographics, clinical presentations and laboratory tests; brain imaging studies, electroencephalography, diagnosis, prognosis, outcome and duration of hospitalization.

RESULTS

A total of 200 patients were admitted with seizures. There were 109 (54.5%) males and 91 (45.5%) females. Among these patients, 193 (96.5%) were aged 1 month to 5 years and 182 (91.0%) presented with seizures and fever. Generalized tonic-clonic seizure was the most common seizure type in 196 (98.0%) children. Febrile seizure was the leading etiology of seizure in 175 (87.5%) children followed by epilepsy in 11 (5.5%) children. There were only 3 (2%) children with central nervous system infections. Abnormal brain images were noted in 10 (20%) out of 50 patients. Among 193 children tested for different infections, 49 (25.4%) had positive results. Viral infections were commonest infections by 49.0%, atypical bacterial 34.7% and 16.3% coinfections.

CONCLUSION

Seizure was the commonest neurological condition of children admitted in our hospital, febrile seizures being the commonest etiology. The prognosis and outcomes were good but there were prolonged days of hospitalization. Children with unprovoked seizures require brain-imaging studies for better understanding of seizure etiology.

Diurnal and Seasonal Occurrence of Febrile Seizures

Investigators from University of Oulu, Finland, evaluated the diurnal and seasonal occurrence of the first febrile seizures (FS) in 461 children in a population-based study of 1522 children.

Inflammation and epilepsy in the developing brain: clinical and experimental evidence

There is an increasing evidence to support a role of inflammatory processes in epilepsy. However, most clinical and experimental studies have been conducted in adult patients or using adult rodents. The pediatric epilepsies constitute a varied group of diseases that are most frequently age specific. In this review, we will focus on the possible role of inflammation in pediatric epilepsy syndromes. We will first describe the clinical data available and provide an overview of our current understanding of the role of inflammation in these clinical situations. We will then review experimental data regarding the role of inflammation in epilepsy in the developing brain. To summarize, inflammation contributes to seizure precipitation, and reciprocally, prolonged seizures induce inflammation. There is also a relationship between inflammation and cell injury following status epilepticus, which differs according to the developmental stage. Finally, inflammation seems to contribute to epileptogenesis even in the developing brain. Based on the available data, we highlight the need for further studies dissecting the exact role of inflammation in epilepsy during development.

Clinical factors associated with invasive testing and imaging in patients with complex febrile seizures

BACKGROUND

Complex febrile seizures (CFSs) are a common diagnosis in the pediatric emergency department (PED). Although multiple studies have shown a low likelihood of intracranial infections and abnormal neuroimaging findings among those who present with CFS, the absence of a consensus recommendation and the diversity of CFS presentations (ie, multiple seizures, prolonged seizure, focal seizure) often drive physicians to do a more extensive workup than needed. Few studies examine the factors that influence providers to pursue invasive testing and emergent neuroimaging.

OBJECTIVE

The objective of this study was to determine the clinical factors associated with a more extensive workup in a cohort of patients who present to the PED with CFSs.

METHODS

Patient visits to a tertiary care PED with an International Classification of Diseases, Ninth Revision, diagnosis of CFS were reviewed from April 2009 to November 2011. Patients included were 6 months to 6 years of age. Complex febrile seizures were defined as febrile seizures lasting 15 minutes or longer, more than 1 seizure in 24 hours, and/or a focal seizure. Charts were reviewed for demographics, clinical parameters (duration of fever, history of febrile seizure, focality of seizure, antibiotic use before PED, and immunization status), PED management (antiepileptic drugs given in the PED or by Emergency Medical Services, empiric antibiotics given in the PED, laboratory testing, lumbar puncture, or computed tomography [CT] scan), and results (cultures, laboratories, or imaging). A logistic regression model was created to determine which clinical parameters were associated with diagnostic testing.

RESULTS

One hundred ninety patients were diagnosed with CFS and met study criteria. Clinical management in the PED included a lumbar puncture in 37%, blood cultures in 88%, urine cultures in 47%, and a head CT scan in 28%. There were no positive cerebral spinal fluid or blood cultures in this cohort. Of the 90 patients, 4 (4.4%) with urine cultures had a urinary tract infection. Of the 53 patients who had head CT imaging, there were no significant findings that guided therapy. The only factor associated with having a lumbar puncture performed was whether empiric antibiotics were used (odds ratio [OR], 2.96; 95% confidence interval [CI], 1.28-6.8). History of a febrile seizure was associated with lower odds of a lumbar puncture (OR, 0.29; 95% CI, 0.12-0.69). In addition, higher age category was also associated with lower odds of a lumbar puncture (OR, 0.53; 95% CI, 0.31-0.91). Those who received an antiepileptic drug had a higher odds of getting a head CT (OR, 3.5; 95% CI, 1.5-8.6). Furthermore, patients presenting with a focal seizure also had higher odds of getting a head CT (OR, 4.89; 95% CI, 1.41-16.9).

CONCLUSIONS

Despite the low utility of associated findings, there are important clinical parameters that are associated with obtaining a lumbar puncture or a head CT as part of the diagnostic workup. National practice parameters to guide evaluation for CFSs in the acute setting are warranted to reduce the amount of invasive testing and imaging.