|
Early Treatment Can Stem Deadly Baby Disease
Reuters News
18 May 2005
BOSTON, May 18 (Reuters) - Transplanting umbilical cord blood to seemingly healthy infants before they develop signs of Krabbe's disease can dramatically prolong the lives of children with the deadly genetic condition, researchers said on Wednesday.
About one in 100,000 newborns have Krabbe's, an inherited disease that destroys the insulation surrounding nerve cells and typically kills a child by age two. About 2 million Americans are carriers. The disease can also show up later in life, usually beginning with vision problems.
Because bone marrow transplants have helped older sufferers, a team led by Maria Escolar of the University of North Carolina at Chapel Hill destroyed the blood-producing cells of 25 young children and replaced them with cells drained from umbilical cords.
Out of the 25, 11 were treated before the appearance of any symptoms while the 14 others had already developed them.
The researchers reported in the New England Journal of Medicine that all of the 11 babies who received the transplant before showing any symptoms survived. Krabbe's symptoms include seizures, excessive crying, difficulty feeding, and stiffness.
"It immediately became obvious that these kids were doing much better," Escolar told Reuters. Most seem normal except for some residual motor problems.
But out of the 14 children in whom the symptoms had already appeared, only six have survived and the toddlers didn't seem to recover from the damage done by the disease. The children have been followed for an average of 3 years.
"It prolonged their lives" but they still have severe developmental problems, she said. "There really is a window of opportunity for treating this."
The transplant must be done quickly, or else its usefulness is severely limited, the researchers said.
The children who got their transplant before symptoms appeared were identified because of a family history of the disease, so doctors knew to test for it. The blood test looks for the absence of an enzyme, galactocerebrosidase.
But such testing usually takes three weeks, and most doctors don't test for Krabbe's because the initial symptoms suggest allergies or acid reflux problems. Only when the baby's muscles tighten up do doctors realize something else might be going on.
"By the time they have the diagnosis, the baby is very symptomatic," she said.
The researchers used umbilical cord blood because it is plentiful. Finding a matching bone marrow donor, as is done for people who develop Krabbe's later in life, can take months. Infants don't have that much time.
"This disease progresses every day," said Escolar. "It's extremely painful for parents to witness this."
The study raises a broader question about how best to treat serious childhood illness, said Kenneth Weinberg of the Children's Hospital in Los Angeles, in an editorial in the Journal.
Transplantation is still considered "a high-risk therapy of last resort," but in this case early aggressive treatment turned out to produce the best results, he said.
"In some circumstances, the subjects who derive the greatest benefit may be those who would otherwise be considered less than ideal research candidates" such as the newborns without symptoms, said Weinberg.
Escolar said the discovery of an effective treatment may encourage insurance companies to cover the transplant, which can cost $600,000.
"The next step is neonatal screening," she said. Further studies will be needed to determine if that is cost-effective.
|
