Underlying neurologic disorders and recurrence rates of status epilepticus in childhood

Background: The underlying neurologic disorders of status epilepticus (SE) in childhood remain poorly characterized. Methods: We reviewed 249 consecutive patients with SE, aged 1 month to 18 years, who were referred to Tottori University Hospital from 1984 to 2002. After exclusion of SE patients with acute symptomatic etiology and progressive encephalopathy, such as acute encephalitis/encephalopathy, meningitis, head trauma, or metabolic disorders, we analyzed 112 patients, aged 3 months to 14 years, and focused on the epilepsy classification and perinatal brain damage in these patients. Results: Major underlying neurologic disorders were non-symptomatic epilepsy (41 patients, 36.6%), perinatal brain damage (15 patients, 13.4%), non-syndromic mental retardation (17 patients, 15.2%), and congenital disorders including chromosomal abnormalities (13 patients, 11.6%). In non-symptomatic epilepsy, childhood epilepsy with occipital paroxysms (Panayiotopoulos syndrome, 11 patients) and severe myoclonic epilepsy in infancy (SMEI, 6 patients) were common and had high recurrence rates (81.8% and 66.7%, respectively). In patients with a history of perinatal brain damage, preterm birth, neonatal seizure, asphyxia, and neonatal hypoglycemia were frequent. Neonatal hypoglycemia and neonatal seizure were related to the recurrence of SE (100% and 87.5%, respectively). They were mostly diagnosed as symptomatic occipital lobe epilepsy. Parieto-occipital paroxysms were associated with a high recurrence rate of SE (80.6%). Conclusions: Although the underlying neurologic disorders of SE are heterogeneous, three specific epileptic syndromes (Panayiotopoulos syndrome, SMEI, and symptomatic occipital lobe epilepsy secondary to neonatal hypoglycemia and neonatal seizure) were the most common causes of SE and were associated with higher recurrence rates.