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

Abstract

SUMMARYObjective: 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). Significance: 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. The minor infections include gastrointestinal infection, respiratory infection (usually of the upper respiratory tract), and others of uncertain origin. For gastrointestinal infection, there is a concept of "benign convulsion with mild gastroenteritis (CwG)." The word "benign" indicates a good prognosis: a very low chance of having unprovoked seizures later in life. [4][5][6] In addition, CwG seems to be a new entity, which was more likely to be categorized as situation-related seizures than epilepsy, although it is not described in the classification of the International League Against Epilepsy (ILAE). 4,5,7 However, for afebrile seizure induced by nongastrointestinal infection, the risk of recurrence of unprovoked seizure is much higher than that for afebrile seizure induced by gastrointestinal infection, 1 whereas another study 3 shows that only this kind of first seizure and first unprovoked seizure would have subsequent unprovoked seizures. This evidence suggests that seizures caused by gastrointestinal infection and nongastrointestinal infection are essentially different: the former is probably in the category of situation-related seizures, whereas the latter may have a likeness to unprovoked seizure.Therefore, we designed this prospective cohort study on three kinds of first afebrile seizures: first afebrile seizure associated with gastrointestinal infection (AS-GI), first afebril...

Clinical outcome of recurrent afebrile seizures in children with benign convulsions associated with mild gastroenteritis

“…Rotavirus is the most common agent associated with CwG. The rotavirus antigen was found in the stool of 22.35% of our patients at the time of initial CwG diagnosis, which is similar to rates in previous reports [3,4,15]. Direct CNS viral invasion and viral enterotoxin NSP4-induced disruption of calcium homeostasis have been hypothesized as possibly underlying the genesis of seizures in CwG [12].…”

“…Zhang et al found that CwG versus AS-nGI and US at onset are two distinguishable kinds, with the latter twos sharing the similar relapse rates. Afebrile seizures recurred in 100% and 92.9% cases diagnosed with AS-nGI and US, respectively [15]. In contrast, in the present study, no cases with two or more episodes of afebrile seizures were found in the AS-nGI group during over 3 years of follow-up, while one of the three patients in the US group presented with US recurrence.…”

“…Previous studies have reported that 4.7%-20% [6,[15][16] of patients have a relapse of CwG, but that patients rarely present with recurrent unprovoked seizures [2,5,12]. The evolution and prognosis of recurrent afebrile seizures after an initial diagnosis of CwG require more investigations and thorough assessment.…”

“…Until now, although cases have been reported in Europe and America [2,6,8,14,28], more cases have been described in East Asian countries, mainly Japan, South Korea and China [3][4][5]7,15,[29][30][31][32], where CwG episodes occur in approximately 1% of all acute gastroenteritis cases [12]. The racial difference suggests that the genetic characteristics of the host play a role in the development of CwG.…”

“…In this study, hospitalized patients diagnosed with CwG were enrolled from October 2009 to December 2014. Previously reported cases [3,15] that occured during this period were included in this study. The inclusion criteria were identical to those described previously [7,16], and included (1) a diagnosis of CwG in previously healthy subjects 6 months to 3 years of age with afebrile convulsions; (2) seizure onset was associated with mild dehydration (< 5% of body weight); (3) seizures occurring in the course of gastroenteritis; (4) normal laboratory examinations (cerebrospinal fluid results, serum electrolytes, and blood glucose levels) were observed.…”