The outcomes of childhood convulsive status epilepticus

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.

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.

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.

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.