Objective: We hypothesized that cryptogenic forms of arterial ischemic stroke (AIS) in children may present better outcomes than symptomatic ones.
Methods: We conducted a single-centered retrospective cohort study using chart reviews of all inpatients aged 0.25-16 years and admitted for AIS or TIA between 1994 and 2007. Sixty-three consecutive children with AIS were divided into 2 stroke categories: first, AIS with an established cause, considered as symptomatic (S), and second, AIS only associated with risk factors, and considered as cryptogenic (C). AIS were further subclassified according to the CASCADE stroke classification system. We measured long-term outcome with 2 endpoints: recurrence rate and neurologic impairment score (NIS). We used univariate analysis to compare the clinical and radiologic characteristics of both groups.
Results: AIS were cryptogenic in 28 patients (44%) and symptomatic in 35 (56%). Compared to patients in group S, patients in group C showed an absence of stroke recurrence under prolonged aspirin treatment (0% vs 30.3%; p < 0.01), a predominance of nonprogressive arteriopathies (p = 0.02), unilateral infarcts (p = 0.01), M1 segment stenosis (p = 0.02), and better stroke outcomes (mean NIS 2.7 vs 4.2; p = 0.04). Within group C, patients with post-varicella arteriopathy (PVA) had a profile comparable to that of patients with non-PVA strokes in terms of infarct topography, localization of vascular lesions, recurrence rate, and neurologic outcome.
Conclusion: Cryptogenic AIS during childhood is a homogeneous clinical and radiologic entity, likely reflecting similar underlying pathophysiologic mechanisms. Under early and prolonged treatment with aspirin, cryptogenic AIS does not recur.