Umbilical cord blood could replace blood marrow transplants

From Reporter Louise Schiavone

WASHINGTON (CNN) -- An experimental procedure to use umbilical cord blood instead of bone marrow to treat immune diseases is gaining attention from doctors and patients.

Derek Kuhs, 7, has spent much of his life in the hospital due to a rare immune system genetic disorder called chronic granulomatous disease, or CGD.

"His white cells can't kick certain types of bacteria and fungi, so he's always open to life-threatening infections," said his mother, Gloria Kuhs.

She and her husband are pinning their hopes on a transplant of umbilical cord blood.

The cord blood, about 3 to 4 ounces taken from a mother's placenta shortly after childbirth, contains stem cells, the building blocks of all blood cells.

If the treatment is successful, the stem cells from the cord blood will survive in a patient's bone marrow and produce healthy white blood cells.

Increasingly, experts say cord blood transplants have distinct advantages over more traditional bone marrow transplants in stimulating the growth of healthy white blood cells.

The collection of cord blood is simple and painless, whereas bone marrow donors must undergo general anesthesia.

Cord blood from an unrelated donor doesn't require the extremely close tissue-type matching of bone marrow transplants, and rejection of placental cells is less severe.

"Some of the complications of bone marrow transplants, particularly one called graft vs. host disease -- where the new cells attack the recipient -- seem to be milder in cord blood transplantation when you compare it with bone marrow transplantation," said Dr. Joanne Kurtzberg of the hematology-oncology department at Duke University Medical Center.

But because stem cells take longer to take hold in the bone marrow, a cord blood transplant requires a longer recovery period than bone marrow transplants.

The National Institutes of Health has begun a five-year study at Georgetown University Medical Center, where Derek is being treated, and at other hospitals to study cord blood transplantation.

Overall, children, who are smaller and generally healthier, respond best to cord blood procedures, and that's what keeps the Kuhs family hopeful for Derek.

"He's probably the toughest person I know," said Rick Kuhs.

Currently, mothers who want to donate cord blood can do so at only a handful of hospitals across the country, with more expected.

While there are millions of potential bone marrow donors, there are just 25,000 units of stored cord blood.

Doctors have recently given Derek a second cord blood transplant. It could be months, perhaps a year, before they know if the treatment will work.

"He continues to amaze me in terms of his ability to brave perilous conditions that you and I might not handle as well," said Dr. Mitchell Cairo, chief of Pediatric Hematology, Oncology and Bone Marrow Transplantation at Georgetown University Medical Center.