Are afebrile seizures associated with minor infections a single seizure category? A hospital-based prospective cohort study on outcomes of first afebrile seizure in early childhood.

Objective: To explore if afebrile seizures associated with minor infections are a single category of seizure, or a set of different kinds of seizures.

Methods: We conducted this prospective cohort study on three kinds of first afebrile seizure: first afebrile seizure associated with gastrointestinal infection (AS-GI), first afebrile seizure associated with nongastrointestinal infection (AS-nGI), and first unprovoked seizure (US). The Kaplan-Meier estimate risks of recurrent seizures were analyzed and compared pairwise. The characteristics of recurrent seizures were also compared pairwise.

Results: The Kaplan-Meier estimate risks of recurrent seizure at 2 years of the AS-GI, AS-nGI, and US groups were 6.9%, 23.7%, and 37.8%, respectively. The pairwise differences were significant between the AS-GI and US groups (p < 0.001) and between the AS-GI and AS-nGI groups (p = 0.001), but not significant between the US and AS-nGI groups (p = 0.066). Among unprovoked subsequent seizures in patients with recurrence, the pairwise differences were significant between the AS-GI and US groups (p < 0.001) and between the AS-GI and AS-nGI groups (p = 0.005), but not significant between the US and AS-nGI groups (p = 0.417).

Conclusions: Afebrile seizures associated with minor infections are indeed of two distinguishable kinds: AS-GI, if free of risk factors such as a family history of epilepsy, had a better prognosis and should be categorized as an acute symptomatic seizure, whereas patients with first AS-nGI, like patients with first US, may have recurrent unprovoked seizures, which suggests this category's essential difference from AS-GI.