Acute symptomatic status epilepticus: Splitting or lumping? A proposal of classification based on real-world data

This study aimed to group acute symptomatic etiologies of consecutive episodes of status epilepticus (SE) into different subcategories and explore their associations with clinical outcome. Etiologies were first categorized as "acute," "remote," "progressive," "SE in defined electroclinical syndromes," and "unknown." Four subcategories of acute etiologies were then defined: (1) withdrawal, low levels, or inappropriate prescription of antiseizure medications, or sleep deprivation in patients with pre-existing epilepsy; (2) acute insults to central nervous system (CNS; "acute-primary CNS"); (3) CNS pathology secondary to metabolic disturbances, systemic infection, or fever ("acute-secondary CNS"); and (4) drug/alcohol intoxication or withdrawal. Poor outcome at discharge, defined as worsening of clinical conditions (modified Rankin Scale [mRS] at discharge higher than mRS at baseline), was reported in 55.6% of cases. The etiological categories of acute-primary CNS (odds ratio [OR] = 3.61, 95% confidence interval [CI] = 2.11-6.18), acute-secondary CNS (OR = 1.80, 95% CI = 1.11-2.91), and progressive SE (OR = 2.65, 95% CI = 1.57-4.47), age (OR = 1.05, 95% CI = 1.04-1.06), nonconvulsive semiology with coma (OR = 3.06, 95% CI = 1.52-6.17), and refractoriness (OR = 4.31, 95% CI = 2.39-7.77) and superrefractoriness to treatment (OR = 8.24, 95% CI = 3.51-19.36) increased the odds of poor outcome. Heterogeneity exists within the spectrum of acute symptomatic causes of SE, and distinct etiological subcategories may inform about the clinical outcome.