(Dutton SBB et al. 2017). Many patients with Dravet syndrome experience prolonged early-life febrile seizures. Although the occurrence of these events in relation to vaccines and the resulting adult presentation has been studied (here), the presence of prolonged febrile seizures themselves and subsequent effects on presentation have not been researched extensively.

This study subjected mice with an SCN1A mutation associated with GEFS+ to extreme temperatures in early life (resulting in a prolonged “febrile” seizure in 75% of the mice), then studied several aspects of epilepsy throughout the mouse life. Early-life febrile seizures resulted in lower thresholds to induced seizures, increased severity of spontaneous seizures, hyperactivity, and impairments in social behavor and recognition memory in adulthood. It should be noted that this study focused on a GEFS+ model, which is associated with a more favorable outcome than Dravet syndrome, and the findings from this study may not extend to DS, whose patients regularly experience these problems even in the occasional absence of prolonged febrile seizures.

Dutton SBB, Dutt K, Papale LA, Helmers S, Goldin AL, Escayg A. Early-life febrile seizures worsen adult phenotypes in Scn1a mutants. Exp Neurol. 2017 Apr 1;293:159-171. doi: 10.1016/j.expneurol.2017.03.026. [Epub ahead of print] PubMed PMID: 28373025.