Welcome to Facts on the Ground a new series brought to you by Natan Cramer, Pediatric Emergency Medicine fellow from the University of Pittsburgh. Facts on the Ground is designed to be a concise literature review that helps answer common clinical questions.
To assess the prevalence of bacterial meningitis and HSV encephalitis in patients with complex febrile seizure. Evaluate in a subgroup analysis the prevalence of meningitis/encephalitis in patients without concerning symptoms/signs but who present with complex febrile seizure.
A complex febrile seizure is defined as either a focal in nature, prolonged (>15 minutes in duration), or recurring (>1 in 24 hours)
This is a retrospective review in France of 7 Pediatric Emergency Departments over 5 years. 839 patients with complex febrile seizure were included. 260 patients had lumbar puncture performed.
Total prevalence of bacterial meningitis was 0.7% (95% Cl 0.2% to 1.6%) among 715 patients who could be followed up on (85% of total sample), cases of HSV were 0% out of 657 patients who could be followed up on (78.3% of total sample). All meningitis cases (n=5) were <12 months of age.
Out of a total of 630 patients without clinical symptoms/signs to suggest meningitis or encephalitis, the prevalence of either was 0% (95% Cl 0% to 0.7% for bacterial meningitis/95% Cl 0% to 0.8% for HSV encephalitis). The most frequent criteria met to diagnose a complex febrile seizure presentation in this cohort were recurrent seizures within a 24 hour time frame (55.8%). 468 patients who only presented with multiple seizure episodes as their defined criteria for complex febrile seizure without other concerning symptoms also had a prevalence of 0% for meningitis/ encephalitis.
All patients with meningitis had prolonged seizure as part of the defined criteria for complex febrile seizure. The prevalence of bacterial meningitis among patients with one brief focal episode was 0% (95% CI 0% to 3.8%).
14.8% and 21.7% of patients could not be followed up on to assess for bacterial meningitis and HSV encephalitis respectively. 4.4% of the 630 patients with no clinical symptoms or signs to suggest meningitis or encephalitis were pre-treated with antibiotics. Vaccine status was not documented in 61% of this cohort.
The Bottom Line
Overall, meningitis and encephalitis are rare in complex febrile seizure. It is even rarer in patients without clinical symptoms or signs to suggest meningitis or encephalitis but who presented with complex febrile seizure. This study can inform discussions with patients, families and colleagues about the need for lumbar puncture in the evaluation of patients with complex febrile seizures.