Abstracts

Rationale: One-third of children with a first febrile seizure (FS) will experience recurrent FS. Prior reports suggest that a prolonged first FS is associated with an increased risk of subsequent prolonged FS(1). Studies of a first FS have only a few children with febrile status epilepticus (FSE) and, therefore, we wished to examine whether there was a propensity for children with a first FSE as their first FS to have recurrent FSE. We examined the risk for recurrent FS of different types in children with a first FS that was FSE compared to children with a first simple FS (SFS), examining any recurrent FS, any FSE, and any FS lasting 10 minutes or more.Methods: Three cohorts with a first FS that was FSE were included in this analysis (2) and followed for 5 years: The subset of 193 FSE without prior FS included, FEBSTAT (N=160), a Duke University FSE cohort (N=18) and the Columbia University first FS study (N=15). A cohort of 101 children with a first simple FS were drawn from the Columbia cohort. Three pediatric epileptologists independently classified the phenomenology of FS and a consensus diagnosis was made. FSE was defined as a febrile seizure lasting > 30 minutes either continuously or repeated seizures without recovery between seizures lastin > 30 minutes. We compared the risk for recurrence using Kaplan-Meier curves, censoring those children who developed epilepsy before a second seizure with fever and those lost to follow-up. The log rank statistic was used to determine a statistically significant difference between groups. The use of rectal diazepam gel was examined all three cohorts among children with a recurrent FS lasting 10 minutes or more (FEBSTAT N=66; Duke N=3; and Columbia N=11).Results: Risk for a second FS of any type was increased 1.8-fold in FSE versus SFS (41.1% vs 28.9%; log rank p=0.12; Figure 1). The risk for any recurrent FSE was increased 4-fold in children with a first FSE compared to a first SFS (8.1% vs 2.3%; log rank p=0.08; Figure 2). Risk for a recurrent FS lasting 10 minutes or more was increased 2-fold in first FSE compared to SFS (13.8% vs 6.4%; log rank=0.11). Across all three cohorts, there were 80 recurrent FS lasting at least 10 minutes. Rectal diazepam was given for 27 FS at home (33.75%).Conclusions: There is a trend suggesting that recurrent prolonged seizures are more common in FSE than in SFS, although these comparisons do not reach statistical significance. Similarly the risk for a recurrent FS that was not FSE is increased but not significant for children with FSE compared to SFS controls. A third of recurrent FS lasting 10 minutes or longer were treated with rectal diazepam at home. As rectal diazepam was routinely prescribed to children with FSE but not to those with a first SFS, this may have led to a lower recurrence of FSE.