Arterial Ischemic Stroke

Little is known about risk factors in pediatric and newborn arterial ischemic stroke (AIS). Risk factors regarding pediatric AIS are evolving and include, in order of prevalence: vasculopathy, infection, cardiac disease, sickle cell disease (SCD), and “other” causes. However, as many as 27% of pediatric and most newborn strokes have no identifiable risk factor.1The incidence of perinatal AIS, defined as occurring one month before to one month after delivery, is approximately 4 per 10 000 full-term babies.2 Direct causes for newborn stroke are not well understood. Predisposing maternal factors may include choreoamnionitis, premature rupture of membranes, and first-time pregnancy.3 The birthing process itself may be a risk, and AIS is likely polygenic. In neonates with hypoxic ischemic encephalopathy (HIE), 10% of those with severe HIE may have focal infarcts. Thrombophilias and vasculopathies as determined by MRA are rare.3 Perinatal stroke does not usually recur.Pediatric AIS is defined as occurring age 1 month through 18 years with a peak at about age 5 years.3 Risk factors include arteriopathies, infection, cardiac disease, blood disorders, and heritability. There is overlapping pathophysiology of many of these risk factors.Arteriopathies may be acute, transient, or progressive and can occur in about 50% of children with AIS, but estimates vary between series.1 The most common arteriopathies are focal arteriopathy of childhood (FAC), Moyamoya, and arterial dissection.1 FAC is coined by the International Pediatric Stroke Study Group (IPSS). Previous studies show an association with infectious agents such as varicella.1,3,4,5 Additionally, arteriopathies are associated with sickle cell disease (SCD) and congenital hypoplastic vessel abnormalities.3,4,5 Once a …