Still, Pruette stresses that all children with untreated hypertension could be at risk. Even those with mild hypertension can develop LVH.
Doctors are still learning the intricacies of the illness in children.
"It's been recognized in adults for several decades, but I think that our attention to LVH in children has probably lagged," said Dr. Susan Mendley, assistant professor and director of pediatric nephrology at the University of Maryland School of Medicine.
Brady, at Hopkins, recommends that when a doctor discovers one episode of elevated blood pressure, the child should be monitored and have further tests to determine if there are underlying causes of the hypertension. Children should have blood and urine tests to rule out kidney problems, which can cause hypertension. And doctors should do an eye exam to rule out eye problems that can trigger hypertension.
In addition, children should also receive an ultrasound of the heart, known as an echocardiogram, to check for LVH, she said. "It's a mistake not to do it," she said.
But some pediatricians say the extensive ultrasound may not be necessary for every child with elevated blood pressure. First, parents should be advised to encourage their child to exercise and limit salty foods, which can cause high blood pressure, said Dr. Charles Shubin, director of pediatrics at Mercy Medical Center in Baltimore.
"How much do you subject a larger population to get that if there is very low incidence of that problem?" he said. Of course, he said, if blood pressure is consistently high, doctors should order tests.
Brady says monitoring is critical because hypertension strikes some children who have no underlying health problems, making it difficult to detect without further tests. If the high blood pressure is severe, children can have symptoms such as bloody noses, headaches and shortness of breath.
"But often, hypertension is silent in kids," said Brady. "The kid looks fine; the kid seems healthy and has no complaints."
Pediatricians tend to carefully screen obese children and those with a family history of hypertension. But for other young patients, doctors may not do blood pressure readings at all, despite recommendations that screening begin at age 3, said Brady, who has researched why doctors miss high blood pressure. And some doctors do not take proper blood pressure readings, which is admittedly a tough task with a squirming child; Brady recommends taking three blood pressure readings during a visit and averaging them.
