ALLENTOWN, PA. — Anne Hosterman sensed something was wrong with her infant daughter soon after she brought 8-pound, 3-ounce Leah home from the hospital.
"She never cried. She was so lethargic," Hosterman recalled of her fourth child.
"I kept taking her back to the doctors, but they just thought she was a happy, contented baby."
It wasn't until Leah was 8 months old that specialists identified the cause of her mother's concern: mild cerebral palsy from a massive stroke.
The prognosis wasn't good. But Leah, now 5, has surpassed doctors' expectations.
Every year, an estimated 4,000 children in the U.S. experience a bleed or blockage of blood flow in the brain more commonly known as stroke, national experts report. That's a fraction of the 780,000 strokes in adults.
With May being National Stroke Awareness Month, Hosterman, of Bethlehem, Pa., shared her daughter's story to let people know that brain attacks can happen to children too, that more cases are being diagnosed, and that researchers are making progress on potential causes.
Although more common among adults, strokes are "not that uncommon" among children, said Dr. Karen Senft, one of Leah's doctors and a developmental pediatrician in Allentown. Senft said she currently sees about 20 children who've had strokes.
In fact, more pediatric cases are being detected because magnetic imaging has permitted doctors to look inside children's brains without the risk of anesthesia, contrast-material injections or radiation, to find evidence of the attacks even years later.
Strokes in children, however, generally have causes and outcomes different from strokes in adults.
According to the National Stroke Assn., adults can blame their strokes on high blood pressure, high cholesterol or a history of smoking, drinking and obesity. Children's strokes generally result from genetic defects, infections, trauma or blood disorders, such as sickle cell anemia.
A recent study in Canada also found that a deficiency of iron, which can be found in breast milk but not cow's milk, was a common element among more than half of the 56 children who had strokes between 1992 and 2004.
More than likely, though, children's strokes have more than one cause, said Dr. Heather Fullerton, a medical director, teacher and researcher at UC San Francisco.
"There's a lot of consensus that several things are going on at once," she said. "There might be a hereditary condition that causes the blood to clot and the child might also have an infection, especially a virus, that causes inflammation or the blood vessels to the brain to narrow."
Fullerton has applied to the National Institutes of Health for a grant to conduct a multi-center study with a researcher in Canada to compare the risks of children with abnormal blood vessels who've had strokes to those who also have had infections, against a healthy control group.
Paralysis, weakness and speech difficulties can result from stroke in both children and adults. But only children develop cerebral palsy, mental retardation and epilepsy, the Stroke Assn. says on its website.
The good news for children is that their brains have a better chance of healing because they are still developing.
One example is 13-year-old Jake Wloczewski of Whitehall Township, Pa., an active player of basketball, baseball and golf ho suffered a stroke at the end of a school day in third grade.
Jake spent two days unconscious in pediatric intensive care while doctors searched for the cause of his numbness, loss of speech and inability to walk, said his mother, Roxanne Wloczewski. When he woke up, his paralysis was gone. Doctors blamed the stroke on migraines, which run in the family but caused a blood vessel in Jake's brain to constrict longer than usual.
Hosterman counts Leah among the 20% of children for whom the cause of stroke is not known. No one in the family had strokes or blood disorders, she said, and experts do not know exactly when her daughter's stroke occurred.
According to Hosterman, Leah's heart rate dropped in utero, when Hosterman had been given an epidural injection in preparation for her baby's scheduled C-section delivery on July 31, 2002. Doctors performed emergency surgery and Leah cried at birth, her mother said. But the newborn developed difficulty breathing on the way to the nursery.
Leah was intubated and put on a respirator in the neonatal intensive care unit, where she recovered, and was sent home six days later.
When doctors made the diagnosis months later, the prognosis was bleak. Children who have strokes in the womb or within the first month of life are especially at risk for cerebral palsy because the brain has been deprived of oxygen.
"We were told it was possible that she'd never walk or talk," Hosterman said.
Today, Leah can talk, walk and run.