Pediatric strokes puzzling but not rare

Washington -- Strokes happen only to older people, right? Not so, say physicians who are finding the often difficult-to-detect disorder in children more frequently than brain tumors.

Getting the word out to primary care physicians is very important to Jill M. Baren, MD, associate professor in the departments of emergency medicine and pediatrics at the University of Pennsylvania. She sees an estimated two cases per week in her busy pediatric center.

In cases of childhood stroke, parents are much more likely to turn first to their primary care physicians for help, she said. "Often a young child is not talking right and it is perceived as acting out. It can be four to six days later that they show up in an emergency department."

And time is critical in stroke treatment for children, just as it is for adults. "Time is brain," Dr. Baren stressed to a group of physicians attending an April 11 scientific meeting of the American College of Emergency Physicians in Washington, D.C. However, 24 hours often elapses between the occurrence of stroke in a child and the time when they receive medical care.

There is no children's stroke program in the United States, although there is such a program at the Hospital for Sick Children in Toronto. And no management program exists beyond those developed for children with sickle cell anemia and congenital heart disease, Dr. Baren said.

For now, applying treatments developed for adults serves as the starting point for emergency department care for these children, she said.

Sickle cell anemia, lupus, moyamoya disease, cavernous angioma and Sturge-Weber syndrome are among the stroke risk factors in children, as are infections such as bacterial meningitis or chicken pox and trauma to the neck as might occur in whiplash or a fall while holding a sharp object, she said. Most childhood strokes occur among 6- to 8-year-olds.

These conditions differ greatly from adult risk factors such as hypertension, diabetes and atherosclerosis.

There has been some recent progress in predicting stroke risk among children and teens with sickle cell anemia. According to research published in the April Nature Genetics, knowing certain variations in 11 genes for these patients might allow physicians to predict the risk of stroke with 98% accuracy. The finding could be a prognostic boon for a major complication of the disease.

Stroke facts

In other findings, researchers who studied 2,278 first admissions for childhood strokes in a 10-year period in California found that ischemic stroke accounted for 51% of the cases and hemorrhagic stroke accounted for the rest. Boys were found to be 28% more likely than girls to have a stroke of any type, and black children had more than twice the overall risk. The findings were published in the July 22, 2003, Neurology.

The impact of childhood stroke is great. It ranks among the top 10 causes of death among children in the United States. Out of those who do recover, 60% have a permanent disability. And there is a risk of recurrence.

Strokes are extremely difficult to detect, Dr. Baren said, as symptoms frequently mimic the flu or other common childhood ailments and include nausea, vomiting, lethargy and headache. Seizures herald strokes in about 30% of children, especially newborns.

The three conditions that most closely mimic stroke symptoms are brain tumors, Todd's paralysis that occurs after a seizure, and migraine headaches, she noted. Although MRIs are the best diagnostic tool for physicians to use when detecting strokes, CT scans might be more readily available and also can be used, she said.

In a move intended to help fill the knowledge gap, Gabrielle deVeber, MD, a staff neurologist at Toronto's Hospital for Sick Children, recently received funding for the first international study to find safe and effective treatments for childhood stroke. Six centers in the United States, three in the United Kingdom and one in Belgium will join with the Hospital for Sick Children in the study.

Dr. deVeber already has developed a national registry that tracks all incidents of pediatric ischemic stroke at 16 children's hospitals and care centers across Canada. The registry now follows more than 1,200 Canadian children. In the past five years, the Hospital for Sick Children has treated 500 children with stroke and sees three to five new cases a week. In addition, a weekly stroke clinic attends to more than 600 children with stroke.

Dr. deVeber said the new study represented "a dream come true." There had been no information available when she began work a decade ago in this area. "Slowly, this is changing. Now, with my colleagues' observations and our observations in the Sick Kids stroke clinic, patients are giving us questions, and our research is giving us answers."