Pediatric status epilepticus: Identification of prognostic factors using the new ILAE classification after 5 years of follow-up

OBJECTIVE: Status epilepticus (SE) is the most common neurologic emergency in childhood. This study aimed to report on a large cohort of pediatric patients with SE, applying the International League Against Epilepsy (ILAE) Classification for SE to identify prognostic factors.

METHODS: We included 173 children treated at "Bambino Gesù" Children's Hospital in Rome for SE exceeding 30 minutes (mean age 4.43 ± 4.93 years old, median 2.28, interquartile range [IQR] 0.41-7.32; follow-up for a mean of 4.9 ± 3.4 years, median 8.75, IQR 4,58-12.63). A multivariate model was constructed to predict neurocognitive outcome, recurrence of SE, development of epilepsy, and mortality. Adjusted odds ratios [ORs] were calculated with 95% confidence interval (OR, 95% CIs).

RESULTS: We observed a different prevalence of etiologies for the different semiologies (P < .05) and for each age group (P < .05), overlapping only in part with the recent ILAE classification. After SE, patients showed 69.9% epilepsy (drug-resistant in half of them), 23.1% worsening of neurologic findings on examination, 28.9% cognitive deficit, and 28.3% recurrent SE. At multivariate analysis: superrefractory SE was correlated to an increased risk of developing cognitive (OR 6.00, 95% CI 2.09, 17.31) or neurologic sequelae (OR 4.9, 95% CI 1.75, 19.77). A similar finding was observed for patients with onset in the neonatal period for cognitive (OR 4.84, 95% CI 1.13, 17.3) and neurologic sequelae (OR 9.03, 95% CI 2.40, 34.04). Recurrence of SE was associated with unknown etiology (OR 6.15, 95% CI 1.43, 26.76), and myoclonic semiology (OR 6.1, 95% CI 1.23, 29.3). Patients with acute symptomatic etiology (OR 0.12, 95% CI 0.04, 0.40) had a lower risk for developing epilepsy.

SIGNIFICANCE: Age at onset and duration of SE were critical independent variables associated with worse neurocognitive outcome. The risk of developing epilepsy was lower after acute symptomatic and febrile SE. Semiology and age at onset correlate with etiology of SE. For this reason, ILAE classification with respect to four axes seems an appropriate advancement.