When Jaundice Leads to Brain Injury

kernicterusDeborah Tripplett

Susan Haas says that when her daughter, Lexi, was born she was a normal, healthy baby girl.

"This was a child who had no issues," said Haas, a Charlotte, N.C.-based medical writer.

So when Lexi, at 3 days old, developed jaundice -- a common liver condition that is estimated to affect six out of every 10 babies -- the doctor was not concerned, Haas said.

That was seven years ago. Today at 6:30 a.m., Lexi, 7, headed into an operating room at Virginia Commonwealth University Medical Center for deep brain stimulation, a form of brain surgery that is currently not allowed on children younger than 7 in the United States.

The surgery represents a relatively new approach to help mitigate the movement disorders that Lexi suffered as a result of her bout with jaundice. Lexi's cerebral palsy and a muscle condition known as dystonia make such everyday activities as walking, reading, talking and writing all but impossible.

During the first part of the surgery, which took place today, doctors inserted a probe deep into Lexi's brain while the girl was kept in a semiconscious state. Next week, Lexi will go back into the operating room, where surgeons will implant the stimulator -- a device that will send electrical impulses to the probe -- under the skin of her abdomen.

It is an extreme measure for a problem that Haas said could have been caught early and treated inexpensively.

"She would not be having any problems if she'd had a $1 bilirubin test," she said. Instead, Haas estimated that medical expenses and other services would cost $25 million over Lexi's life.

Kernicterus a Rare but Severe Condition

Fortunately, the vast majority of parents whose newborn children develop jaundice will never see the condition progress to kernicterus.

According to the U.S. Centers for Disease Control and Prevention, the exact number of newborns who suffer from the condition is unknown, but it appears to be remarkably small. Preliminary research has suggested that the risk of developing the condition is only about one in 13,300. Other doctors say the chances are much lower.

But the conditions that lead up to the rare condition are far more familiar. The root cause is excessive jaundice, a well-known condition in which the levels of a substance called bilirubin build up in a baby's blood faster than it can be broken down in the liver.

This condition generally poses little threat to health, beyond its characteristic yellowing of the skin and whites of the eyes.

But when bilirubin levels in the blood spike high enough, the toxic byproduct can move out of the blood and into brain tissue. This opens the door to kernicterus -- and, in turn, brain damage.

"Before people knew that high levels of bilirubin could cause brain damage... about 10 percent of cerebral palsy used to be due to kernicterus, [which is] due to jaundice," said Dr. Steven Shapiro, the pediatric neurologist at Virginia Commonwealth University, who, in 2004, diagnosed Lexi with kernicterus.

Using a bilirubin test, doctors can catch high bilirubin levels early. Lowering these levels may involve therapy that is as simple as phototherapy -- in other words, treatment with light -- which transforms the toxic version of bilirubin into a nontoxic form that the body can easily eliminate. In severe cases, babies can receive blood transfusions to get rid of the bilirubin before it has a chance to damage their brains.

Haas said her daughter never received such a test. So when her bilirubin levels spiked, Lexi began to suffer from brain damage without doctors or her parents knowing.

But the brain damage that Lexi suffered was highly specific to an area known as the globus pallidus, which is crucial in controlling voluntary movements. Consequently, Lexi is unable to move normally, but her mental faculties remain unaffected.

"Even though they look retarded because they can't move, can't talk normally, they are bright kids trapped in these bodies that don't work because of their dystonia," Shapiro said.

Will Deep Brain Stimulation Offer Hope?

Lexi may very well represent the first case in which a deep brain stimulation procedure is being used to treat someone with kernicterus, brain experts said.

Because kernicterus appears to have affected this one small area of Lexi's brain so profoundly, leaving the rest relatively untouched, the idea that the electrical current delivered through a probe placed at the exact right spot in the brain is a tantalizing one.

"[Deep brain stimulation] has been successful in people with a genetic form of dystonia," Shapiro said. "Other kinds of dystonia have not responded to deep brain stimulation, and nobody knows why.

"In kernicterus we have no idea; we don't know if it's going to work," Shapiro said. "We think there is a reasonably good chance that it will work, and she's so bad off with her dystonia that the potential benefits to her outweigh the risks."

Other doctors not directly involved with the case agreed that the technique may be worth a shot.

"I suspect most of the movement disorders in these children begin at a very early age," said Dr. Jeffery Arle, a neurosurgeon at Lahey Clinic in Burlington, Mass. "They have progressive problems in their entire development period making an abrupt solution and 'fix' with [deep brain stimulation] difficult -- though not impossible to consider. ... I would not rule it out as a plausible treatment option."

But for Haas, who had been waiting for Lexi to turn 7 in order to be eligible to receive the treatment, the procedure at least offers some hope.

While the treatment will likely take between four to six months to show any evidence of effect, Haas said she believes her daughter's young brain may be able to "rewire" itself through the treatment.

"She will hopefully learn how to talk and, her doctor said, with a miracle, will learn how to walk," Haas said. "If we can get to the point where we improve her communication, [help her] go to college or hold down a job, the picture changes completely."