Updated

By donating cells from her pancreas, a Japanese mother has ended her daughter's type 1 diabetes — at least for now — say the doctors who performed the transplant operation.

WebMD first reported the news in February. Now, the doctors have described the case in a research letter to The Lancet. The letter appears in the journal's early online edition for April 19.

Mother and daughter are both doing well, and the daughter no longer needs insulin injections, write the doctors, who included Shinichi Matsumoto, MD, PhD, of Kyoto University Hospital's transplantation unit.

But the procedure is not without risks, and the result — achieving insulin independence — may not last forever, they note.

Mother-Daughter Donation

The 27-year-old diabetes patient had had type 1 diabetes for 12 years. Before the operation, she frequently experienced severe low blood sugar that often led to comas.

Ending those hypoglycemic episodes was the operation's main goal, say Matsumoto and colleagues.

The young woman's mother — a healthy 56-year-old without diabetes — donated half of her pancreas. Insulin-producing cells — called islet cells — were transplanted to her daughter.

The transplanted cells immediately started working. The daughter was weaned off insulin injections gradually; after 22 days, her body was able to detect blood sugar levels and make all the insulin she needed. She still doesn't need insulin injections and has "excellent" blood sugar control, say her doctors.

Long-Term Results Not Known

No one knows how long the results will last, say Matsumoto and colleagues.

Islet cells from living donors could possibly last — and provide good blood sugar control — in more than 80 percent of recipients for at least five years, they write.

They predict that might be true for their patient and that she could avoid low blood sugar comas "even if she needs insulin injections in the future."

The procedure is "not yet a perfect technique," write Stephanie Amiel MD, FRCP, and colleagues in a commentary in The Lancet. "Insulin independence is by no means certain and is only likely in the very insulin sensitive." Amiel is a professor of diabetic medicine at King's College London.

Two U.S. attempts at islet-cell transplantation from living donors failed, says Matsumoto in The Lancet.

Not for Everyone With Type 1 Diabetes

About a million people in the U.S. have type 1 diabetes, most of whom can manage their condition with daily insulin injections. However, some still have dangerous and potentially fatal blood sugar swings.

In February, islet cell transplant pioneer James Shapiro, MD, told WebMD that perhaps one in 10 people with type 1 diabetes might be a candidate for transplants.

When islet cells come from deceased donors, the recipients must take medications for the rest of their lives to prevent their bodies from rejecting the donated cells. Those drugs can have side effects including increased risk of infection, mouth sores, and stomach problems. They have also been linked to a higher risk of cancer.

However, when islet cells come from a living donor, those drugs aren't needed, say Matsumoto and colleagues.

Potential Health Impact for Donor

Donating too much of the pancreas can raise the risk that the donor will develop diabetes. Matsumoto and colleagues suggest ruling out obese people as potential donors for health reasons.

The mother who donated half of her pancreas was not obese, they note.

Even in an ideal donor, the risk of developing diabetes might not be able to be completely eliminated, they say. The surgery itself also runs the risk of complications.

Ethical Questions

Donor safety issues make it "difficult to justify" live http://www.foxnews.com/story/0,2933,136088,00.html islet-cell transplantation if pancreatic cells from deceased donors are available, says a commentary in The Lancet.

Due to cultural taboos, organ donation is particularly rare in Japan.

"Matsumoto's group is in a position to ethically explore whether [living] donors can safely provide more robust successes, and the diabetes world should watch their progress with great interest," write Amiel and colleagues.

By Miranda Hitti, reviewed by Brunilda Nazario, MD

SOURCES: Matsumoto, S. The Lancet, April 19, 2005; online edition. Amiel, S. The Lancet, April 19, 2005; online edition. News release, The Lancet. WebMD Medical News: "Live-Donor Transplant May Treat Diabetes."