U.S. scientists have found that 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.
Approximately one in 100,000 newborns have Krabbe's disease, an inherited illness that destroys the insulation surrounding nerve cells and usually kills a child by the age of two.
The disease can also manifest itself later in life, usually beginning with vision problems.Two million Americans are thought to be carriers.
Krabbe's symptoms include seizures, excessive crying, difficulty feeding, and stiffness.
Bone marrow transplants have helped older sufferers, and this led Maria Escolar and a team from the University of North Carolina at Chapel Hill to surmise that destroying the blood-producing cells of young children and replacing them with cells drained from umbilical cords, might be a way of treating the disease before the children became ill.
Of the 25 children treated, 11 were treated before the appearance of any symptoms while the 14 others had already developed them.
The researchers reported that all of the 11 babies who received the transplant before showing any symptoms survived, and Escolar says it was immediately obvious that the children were much better and 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 did not recover from the damage already done by the disease, it prolonged their lives but they still have severe developmental problems.
The children have been followed for an average of 3 years.
The researchers say it shows that there is a window of opportunity for treating the disease and the transplant must be done quickly, or else its usefulness is severely limited
The children who received 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, and such testing usually takes three weeks.
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 which time the baby is very symptomatic.
Escolar says the disease progresses every day and is extremely painful for parents to witness.
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 and the infants don't have that much time.
Kenneth Weinberg of the Children's Hospital in Los Angeles says the study raises a broader question about how best to treat serious childhood illness, and 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.
Escolar said the discovery of an effective treatment may encourage insurance companies to cover the transplant, which can cost $600,000.
She says the next step is neonatal screening.
The report is published in the New England Journal of Medicine.