The outcomes of childhood convulsive status epilepticus

Abstract

Background: Few studies focus specifically on childhood convulsive status epilepticus (CSE). Geographical differences and study design may influence research findings. A comprehensive understanding of the outcomes of childhood CSE needs to bear these factors in mind when examining the published literature. A systematic review of the outcome of childhood CSE was carried out more than a decade ago. Since then, there have been major prospective studies (in the United Kingdom, the United States of America, and in sub-Saharan Africa (SSA)) focused on childhood CSE.

Methods: Six major prospective studies are described, and their results combined through a narrative synthesis with findings of the earlier systematic review. The following CSE outcomes are described: (1) recurrence; (2) short-term mortality; (3) subsequent epilepsy; (4) neurological, cognitive, and behavioral impairments outside of epilepsy; (5) long-term mortality; (6) association with hippocampal injury and mesial temporal sclerosis (MTS); and (7) white matter changes.

Results: One-year recurrence after the first-ever CSE, whether its prolonged febrile seizures (PFS) or non-PFS, is 16% (95% confidence interval [CI]: 10-24). Twenty percent will have a recurrence within 4 years. Case fatality during hospitalization in high income countries is 2.7-5.2%, and 15% in SSA. The cumulative incidence of subsequent epilepsy nine years post-CSE is 25% (95% CI: 16-36). Neurological, cognitive, and behavioral impairments outside of epilepsy are detectable within 6 weeks of CSE. This persists at one year, and by 9 years follow-up, at least at third of subjects will be affected. Long-term mortality ranges from 5 to 17%, with the true estimate at 9 years follow-up to be 8% with standardized mortality ratio of 46. Mesial temporal sclerosis is uncommon, and decreased hippocampal volume is seen in both PFS and non-PFS. Duration is not but etiology/CSE type is, associated with outcome.

Conclusion: Childhood CSE is associated with substantial morbidity and mortality. Etiology but not duration is the main determinant. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures.

Keywords: Childhood; Outcomes; Pediatrics; Status epilepticus.