Causes of fever in febrile seizures

The causes of pyrexia in 100 cases of febrile seizures were studied. The fever was due to a viral infection in 71 percent, primary complex in 15 percent, due to bronchopneumonia and lobar pneumonia in 8 per cent and 1 per cent cases were due to otitis media. No case of urinary tract infection, enteric fever or infective diarrhea was seen.     

Frequent fever episodes and the risk of febrile seizures: The Generation R Study

Aim

To examine the association between the number of fever episodes and the risk of febrile seizures.

Methods

This study was embedded in a population-based prospective cohort study from early foetal life onwards. Information about the occurrence of febrile seizures and fever episodes was collected by questionnaires at the ages of 12, 24 and 36 months. Analyses were based on 3033 subjects. The risk of febrile seizures was compared between children with frequent fever episodes (>2 per year), and children with only 1 or 2 fever episodes per year.

Results

The frequency of fever episodes was not associated with the risk of febrile seizures in the age range of 6-12 months. In the second and third year of life, having more than 2 fever episodes was associated with an increased risk of febrile seizures (odds ratios 2.02 [95% confidence interval 1.13-3.62] and 2.29 [95% confidence interval 1.00-5.24], respectively). In the age range between 6 and 36 months, we observed a significant trend between the frequency of fever episodes (<2, 3-4 or >4 per year) and the risk of febrile seizures (p-value for trend < 0.001). The association between the number of fever episodes and the occurrence of febrile seizures was stronger for children with recurrent febrile seizures.

Conclusion

Frequent fever episodes are associated with an increased risk of febrile seizures in the second and third years of life. Further studies are needed to identify the mechanisms underlying this association.     

Generalized tonic-clonic and febrile seizures

In general, children with febrile seizures have a good prognosis, and only a small minority of children go on to become epileptic. Most outgrow the tendency to have seizures, and the seizures do not appear to cause lasting intellectual or neurologic damage. Relatively few children need be exposed to daily anticonvulsant therapy, and these would be primarily children whose clinical picture is quite atypical.     

Treatment of febrile seizures

OBJECTIVE: To review basic concepts of febrile seizures and the indications of specific tests. To analyze the prognosis and the medical treatment. SOURCES: The author reviewed the literature and presented her published data. SUMMARY OF THE FINDINGS: The key points are based on the rules of the American Academy of Pediatrics designed according to a consensus about when and how to investigate febrile seizures, and indications of treatment. CONCLUSIONS: Febrile seizure is a benign entity and most children will present only one seizure during their lives. There is no indication of complementary tests (electroencephalogram, lumbar puncture and neuroimaging tests) and specific treatment for this group of children. Special indications are revised.     

Family history and recurrence of febrile seizures

To determine the value of a detailed family history for the assessment of the risk of recurrence of febrile seizures, 115 children who visited the emergency room of an academic children's hospital were studied prospectively. The recurrence risk of febrile seizures was analysed in relation to the child's family history and the proportion of relatives affected by febrile seizures using Kaplan-Meier estimates and Cox proportional hazard models. A first degree family history positive for febrile seizures (parents or siblings affected by febrile seizures) increased a child's two year recurrence risk from 27 to 52%. No significant increase of recurrence risk for febrile seizures was found in children with second degree relatives (grandparents and uncles/aunts) or cousins only affected by febrile seizures. Recurrence risk was significantly correlated with the proportion of first degree relatives affected by febrile seizures: risks were 27, 40, and 83% in children whose proportion was 0, 0-0.5, and > or = 0.5 respectively. Analysis of the recurrence risk in relation to a weighted proportion, adjusted for the attained age and sex of first degree relatives, showed similar results. It is concluded that the application of the proportion of first degree relatives affected by febrile seizures generates a more differentiated assessment of the recurrence risk of febrile seizures.     

Prolactin levels in febrile and afebrile seizures

Transient hyperprolactinaemia has been reported to follow unprovoked seizures, a finding proposed to be useful in the differential diagnosis of epilepsy. There is also evidence that patients with unprovoked seizures may have high baseline prolactin levels, which could be of value in detecting those predisposed to epilepsy after a first convulsive attack. The purpose of this study was to examine whether prolactin levels are elevated: (1) postictally in febrile seizures and (2) interictally in afebrile seizures. In 17 children with simple febrile seizures, mean postictal prolactin value (370±160 mU/l, mean±SD) was significantly higher (0.001) than the mean baseline value of 18 seizure-free controls (202±136 mU/l). The mean baseline prolactin values were not significantly different: (1) in ten children with afebrile versus ten seizure-free controls and (2) in 18 children with febrile seizures associated with high risk for subsequent afebrile seizures versus 23 children with febrile seizures but unlikely to suffer from afebrile seizures.Conclusion Postictal prolactin levels may be a useful marker of recent febrile seizures, while baseline prolactin levels do not appear to have any prognostic significance in afebrile seizures.     

Long term prophylaxis of febrile seizures

Four different prophylactic regimen were tried in a group of 120 children, admitted for first attack of febrilc seizures, and followed up for a period of 5–6 years. The most effective regimen found to be, was with antipyretic and diazepam during the period of febrile illness. Continuous, as well as intermittent phenobarbitone therapy was found to be ineffective in preventing recurrence.     

Assessment of febrile seizures in children

Febrile seizures are the most common form of childhood seizures, affecting 2–5% of all children and usually appearing between 3 months and 5 years of age. Despite its predominantly benign nature, a febrile seizure (FS) is a terrifying experience for most parents. The condition is perhaps one of the most prevalent causes of admittance to pediatric emergency wards worldwide. FS, defined as either simple or complex, may be provoked by any febrile bacterial or (more usually) viral illness. No specific level of fever is required to diagnose FS. It is essential to exclude underlying meningitis in all children with FS, either clinically or, if any doubt remains, by lumbar puncture. There is no evidence, however, to support routine lumbar puncture in all children admitted with simple FS, especially when typical clinical signs of meningitis are lacking. The risk of epilepsy following FS is 1–6%. The association, however small, between FS and epilepsy may demonstrate a genetic link between FS and epilepsy rather than a cause and effect relationship. The effectiveness of prophylactic treatment with medication remains controversial. There is no evidence of the effectiveness of antipyretics in preventing future FS. Prophylactic use of paracetamol, ibuprofen or a combination of both in FS, is thus a questionable practice. There is reason to believe that children who have experienced a simple FS are over-investigated and over-treated. This review aims to provide physicians with adequate knowledge to make rational assessments of children with febrile seizures.     

Brugada syndrome masquerading as febrile seizures

Fever can precipitate ventricular tachycardia in adults with Brugada syndrome, but such a link has not been reported in children. A 21-month-old white girl presented repeatedly with decreased conscious level and seizures during fever. During a typical episode, rapid ventricular tachycardia was documented. The resting 12-lead electrocardiogram revealed a Brugada electrocardiogram signature. Resting electrocardiograms of the asymptomatic brother and mother were normal, but fever in the mother and pharmacologic stress with ajmaline in the brother revealed Brugada electrocardiogram features. Genetic testing revealed an SCN5A mutation in the affected family members.     

Intermittent clobazam therapy in febrile seizures

Objective: To evaluate the efficacy of intermittent clobazam therapy in preventing the recurrence of febrile seizures and to assess its safety.Methods: The study was a prospective, randomized, double-blind placebo-controlled trial conducted in the Department of Child Health, Christian Medical College Hospital, Vellore between July 2001 and September 2002. Neurologically normal children between 6 months and 3 years of age with a history of febrile seizures and no evidence of acute CNS infection or EEG abnormality were included into the study. 19 children in a clobazam group and 20 in the placebo group were randomly allocated. Temperature reduction measures with paractamol and tepid sponging were advised to all children. In addition the dispensed medication was to be administered at the onset of fever and continued for 48 hours irrespective of the duration of fever. The children were then monitored for seizures and adverse effects of clobazam. The children were followed up for a mean period of 9.9 months. The analysis was done on the number of febrile episodes in both the groups.Results: There were a total of 110 episodes of fever during the study period. Mean number of febrile episodes in the clobazam group was 3.1 and in placebo group 2.56. Six (12.5%) of the 48 episodes in placebo group and one (1.7%) of 60 episodes in clobazam group had seizure recurrence. This was statistically significant (p=0.01). Drowsiness and weakness were present equally in both clobazam and placebo group whereas ataxia was present only in the clobazam group, the difference being statistically significant (p=0.04).Conclusion: Intermittent clobazam therapy is an effective measure in the prevention of recurrence of febrile seizures. The ataxia due to clobazam was much lower than that reported with diazepam.     

Circadian and seasonal variation of first febrile seizures

Time of occurrence of 188 first febrile seizures (FS) was recorded, both by four 6-hour periods and by hourly intervals. The frequency of events was significantly ( P < .001) increased from 6 to 11.59 pm with a peak between 5 and 8 pm . A seasonal peak was observed in January.     

Family history and recurrence of febrile seizures.

To determine the value of a detailed family history for the assessment of the risk of recurrence of febrile seizures, 115 children who visited the emergency room of an academic children's hospital were studied prospectively. The recurrence risk of febrile seizures was analysed in relation to the child's family history and the proportion of relatives affected by febrile seizures using Kaplan-Meier estimates and Cox proportional hazard models. A first degree family history positive for febrile seizures (parents or siblings affected by febrile seizures) increased a child's two year recurrence risk from 27 to 52%. No significant increase of recurrence risk for febrile seizures was found in children with second degree relatives (grandparents and uncles/aunts) or cousins only affected by febrile seizures. Recurrence risk was significantly correlated with the proportion of first degree relatives affected by febrile seizures: risks were 27, 40, and 83% in children whose proportion was 0, 0-0.5, and > or = 0.5 respectively. Analysis of the recurrence risk in relation to a weighted proportion, adjusted for the attained age and sex of first degree relatives, showed similar results. It is concluded that the application of the proportion of first degree relatives affected by febrile seizures generates a more differentiated assessment of the recurrence risk of febrile seizures.