The clinical and EEG features, the occurrence of subsequent seizures, and the neurologic outcome in 50 children who had febrile seizures (FS) after 5 years of age were studied at the University of British Columbia, Canada. FS had occurred before 5 years of age in 38, and recurred before 5 years in 27. In addition to this group with both early and late FS occurrence, 12 had the first FS after 5 years of age. There was no significant difference between these two groups with respect to early history, EEG or outcome. During a 1-13 year follow-up (median, 5 yrs 6 mths), 40 had two or less FS after 5 years, and none occurred after 10 years of age. FS were complex in 20 (40%), and 16 (32%) had a family history of FS in a first-degree relative. Afebrile seizures developed in 5 (10%), 18 (36%) had school difficulties, and 9 (18%) had abnormal psychological tests. Learning difficulties in 18 were associated with developmental delay in 33%, motor incoordination in 44%, and afebrile seizures in 22%. Epileptiform EEGs occurred in 22 (44%). [1]

COMMENT. Children with febrile seizures that occur late, after 5 years of age, have a higher frequency of recurrence of early onset FS, complex FS in 40%, a remission of FS before 10 years, a strong family history of FS, afebrile seizures in 10%, and a risk of learning disabilities in one third. Other factors known to influence the outcome of FS, such as the height of the fever at the time of the seizure (“FS threshold“), and the duration of the FS, would have been of interest [2]. The 32% familial incidence observed in the Canadian study is similar to that in an unselected group of 95 FS patients followed in my own clinic. The evidence for an inherited predisposition to FS was equally strong in those who had afebrile in addition to FS.

Rectal diazepam gel for treatment of acute repetitive seizures in children at home is evaluated by an analysis of pediatric data from two previously published reports of the effects of Diastat (DZP) in children and adults [3]. Comparing the results of 68 DZP-treated children and 65 receiving placebo, the DZP group showed a significant reduction in median seizure frequency, and more DZP-treated children remained seizure free at the completion of the 12-hour observation period (40 vs 20, P=.001). Doses of Diastat were based on age and weight: 0.5 mg/kg for ages 2-5 years; 0.3 mg/kg for ages 6-11 years; and 0.2 mg/kg at 12 years and older. Somnolence occurred more frequently in the Diastat group of patients (25% vs 7.7%, P=.009), but no instance of serious respiratory depression was reported. Rectal DZP is effective and relatively safe when used to abort an episode of acute repetitive seizures in a child, and seizure recurrence is lessened in a 12 hour observation period. A single dose is recommended, but if seizures are refractory, a second dose has proven safe after 4 hours.