Yield of emergent neuroimaging among children presenting with a first complex febrile seizure

The objective of this study was to assess the risk of intracranial pathology requiring immediate intervention among children presenting with their first complex febrile seizure (CFS).

This is a retrospective cohort review of patients 6 to 60 months of age evaluated in a pediatric emergency department between 1995 and 2008 for their first CFS. Cases were identified using computerized text search followed by manual chart review. We excluded patients with a prior history of a nonfebrile seizure disorder or a prior CFS, an immune-compromised state, an underlying illness associated with seizures or altered mental status, or trauma. Data extraction included age, sex, seizure features, prior simple febrile seizures, temperature, family history of seizures, vaccination status, findings on physical examination, laboratory and imaging studies, diagnosis, and disposition.

We identified a first CFS in 526 patients. Two hundred sixty-eight patients (50.4%) had emergent head imaging: 4 patients had a clinically significant finding: 2 had intracranial hemorrhage, 1 had acute disseminated encephalomyelitis, and 1 patient had focal cerebral edema (1.5%; 95% confidence interval, 0.5%-4.0%). Assigning low risk to patients not imaged and not returning to the emergency department within a week of the original visit, the risk of intracranial pathology in our sample was 4 (0.8%; 95% confidence interval, 0.2%-2.1%) of 526. Three of these 4 patients had other obvious findings (nystagmus, emesis, and altered mental status; persistent hemiparesis; bruises suggestive of inflicted injury).

Very few patients with CFSs have intracranial pathology in the absence of other signs or symptoms. Patients presenting with more than one seizure in 24 hours in particular are at very low risk.