Recent developments in childhood arterial ischaemic stroke.

Stroke is increasingly recognised as a cause of childhood disability and lifelong morbidity: population-based estimates of the annual incidence of childhood stroke (ischaemic and haemorrhagic) range from 2.3 to 13.0 per 100,000 children, and incidence rates in neonates are closer to 1 per 5000 livebirths. Stroke in childhood can have many causes. Diagnosis is often delayed owing to low clinical suspicion and the need to exclude the frequent mimics of stroke in childhood. Outcomes are related to presentation, associated illnesses, the underlying cause, size, and location of the infarct, and stroke subtype, but more than a half of the children who have had a stroke will have long-term neurological sequelae. Furthermore, estimates of recurrence rates range from 6-19% in the first few years. Arteriopathy-including arterial dissection and other progressive and non-progressive arteriopathies-might account for up to 80% of childhood stroke in otherwise healthy children. Because children with cerebrovascular abnormalities are at the highest risk of recurrence (66% at 5 years), understanding of the nature and course of these arteriopathies is crucial to the development of secondary stroke prevention strategies.