In 203 consecutive children with febrile seizures, no clear associatio
n (odds ratio = 1.0 [95% CI, 0.9-1.1], P = .59) was found between seiz
ure duration and blood leukocytosis (greater than or equal to 15.0.10(
9) cells/L). Increased leukocyte counts may be misinterpreted because
of seizure duration. In children with febrile seizures, leukocyte coun
ts should be used to evaluate the underlying cause of fever.