Abstracts

Status epilepticus (SE) is the most common neurological emergency in childhood. Population-based estimates of the incidence, aetiology, treatment, and natural history of SE are required for appropriate allocation of resources for management of SE. There are few population-based studies on SE, and all such studies have been primarily or exclusively based on adult populations. Thus, a population-based study that primarily addresses SE in a paediatric population is required. The North London convulsive STatus EPilepticus in childhood Surveillance Study ([italic]NLSTEPSS[/italic]), an ongoing study, is such a population-based study.
In [italic]NLSTEPSS, [/italic]all children aged 29 days to 15 years with convulsive status epilepticus (CSE) within North London are identified using a multi-tiered notification system involving a research collaborative network of paediatricians from all hospitals in North London. Details of the event are obtained within two weeks of notification. Incident cases are defined as lifetime first episodes of CSE. Occurrence is defined as the total number of cases/100000children/yr. The childhood population of North London, derived from Census 2001, was the denominator in incidence and occurrence estimations. SE is classified as PFC, acute symptomatic, remote symptomatic, idiopathic/cryptogenic, unclassified. PFC is defined as SE during a febrile ([gt]38[deg]C) illness in a previously neurologically normal child, aged between 6 months and five years, in the absence of CNS infection. In contrast, SE is classified as acute symptomatic if it occurs in a previously neurologically normal child within a week of a defined acute neurological insult.
148 (median age 3.0 years, range 0.08-15.9 yrs, 72 males) episodes have been identified. The occurrence is 33/100000 children/yr (95%CI 27-38/100000children/yr). Relative risk (RR) of occurrence was 2.7 for non-white compared to white children. 79 (67%, median age 2.0 years, range 0.08-15.9 yrs, 44 males) were incident (incidence 18/100000 children/yr, 95% CI 14-22/100000 children/yr). 78% of children were under 5 years old and 49% were under one year old. 27 children (35%) had PFC, 10 (13%) had acute symptomatic, 29 (36%) remote symptomatic, eight (10%) idiopathic/cryptogenic, and five (6%) were unclassified SE. During hospitalisation, 4 children (5%) died. Three had meningitis and one had glutaric aciduria type I. Intensive care was required in 36 (46%) cases.
The incidence of CSE in childhood is approximately 18/100000 children/yr and is most common in the younger age range. Non-white children are at greater risk of CSE than white children. The reason for this is unclear but data on the effect of socioeconomic status is being analysed. PFC is a significant cause for CSE in childhood accounting for a third of incident cases. Fatality during hospitalisation is low but is most likely to be associated with an acute symptomatic cause.
[Supported by: The Wellcome Trust]