Thursday, November 02, 2006

Wired News: Stem-Cell Fix for Diabetic Ulcer

For the last couple days I have been feverishly working on a set of stories about stem cell therapies in India. I have been very impressed with the facilities available here in Chennai, and am beginning to think that India has a strong shot at becoming a world leader in stem cell therapy. While research still lags behind the Unites States and Europe, Indian doctors are making bold steps in designing treatment regimes that have not been successful elsewhere. Here is one example that I recently wrote about in Wired News.

Stem Cell Fix for Diabetic Ulcer?

CHENNAI, India -- Vamal Cattacha didn't pay much attention to the pinprick-size sore on the back of her leg, and before she knew it the oozing wound had spread 22 inches, from her instep all the way up to her calf. And it was beginning to smell bad.

When Vamal, a 68-year-old diabetic, finally sought treatment for the nasty-looking wound, many doctors said it was too late to save her leg. She traveled up and down the coast of India, searching out doctors offering miracle cures, but every respectable medical practitioner said her leg would have to be amputated. And it would have to happen fast, lest the ulcer spread further and turn gangrenous.

After several bouts of bad news, Vamal visited vascular surgeon S.R. Subrammaniyan at Vijaya Hospital here. Subrammaniyan, who works closely with a stem-cell research facility, came to the conclusion that an experimental treatment involving stem cells harvested from Vamal's bone marrow could be her only hope for saving the leg. An angiogram showed she had almost no circulation in the limb.

"She was otherwise in good health, and an ideal patient to try this treatment," said Subrammaniyan, who had read about the success of similar procedures performed in Poland, Japan and China.

Once Vamal was admitted to Vijaya Hospital, bone marrow was drawn from her hip and the sample was rushed to a nearby lab, where technicians used a specialized cold centrifuge to extract stem cells. The sample had to be kept at a constant temperature of 25 degrees Fahrenheit or the cells would begin to deteriorate.

The results of the harvest were promising: Out of 108 milliliters of bone marrow, the lab workers got 14 milliliters of stem cells. It was a good yield.

After preparing the wound, Subrammaniyan injected the concentrated solution of stem cells back into Vamal's leg two times over the next week and waited anxiously for evidence of improvement. Because the wound was so large, he also grafted a piece of skin from her thigh over the ulcer.

The results were nothing less than miraculous.

Within 60 days, the ulcer had visibly healed, and bright, white signatures of arteries streaked across her post-treatment angiograms. The stem cells had apparently re-formed significant lengths of her atrophied circulatory system.

"No one quite knows how it works," said Subrammaniyan, "but somehow, once injected, the stem cells know how to transform into the right sort of cells."

Still, an isolated success story does not necessarily signify a revolution in ulcer treatment.

"This was a single case with no controls," wrote Geoffrey Gurtner, associate professor of surgery at Stanford University and an expert on diabetes care, in an e-mail. "We know that in any disease states, some patients get better even in the absence of care for reasons we do not entirely understand."

A recent The New England Journal of Medicine article, he pointed out, deflated media hype surrounding studies in which doctors transplanted stem cells into damanged hearts. The results are promising, but mixed, the authors found, and more study is necessary before anyone can declare the treatment a cure.

Still, Gurtner commended the Chennai team "for the high-throughput manner in which they isolated and purified the bone marrow cells," calling the method "a real contribution" to stem-cell research.

Diabetes sufferers could use the type of medical breakthrough hinted at by Vamal's recovery. The number of diabetics is on the rise around the world, and amputation is often the only option left to doctors treating patients with critical limb ischemia, a condition that develops in people with severely decreased blood flow in their lower extremities. The problem is a particularly dramatic consequence of diabetes.

According to the American Diabetes Association, patients with diabetes undergo 60 percent of non-trauma-induced amputations in the United States, totaling 82,000 severed limbs in 2002.

India is even worse off than some other places, Subrammaniyan said. He predicts that by 2015, 10 to 15 percent of the population will suffer from some form of diabetes, up from 4 percent today. That would mean more than 100 million diabetics in a country still racked with severe poverty and weak medical infrastructure.

At the moment, the best treatments for diabetics with critical limb ischemia are surgery to bypass atrophied arteries and certain drug regimens that are not always effective.

For Subrammaniyan, stem cells will be a necessary part of the future. And what's more, stem-cell treatments could be quite cheap: Vamal's procedure cost less than $2,000. That's more than most Indians can afford, but over time the cost probably would come down.

More importantly, a significant advance in stem-cell therapy could mean the difference between patients walking away from treatment and spending their lives in wheelchairs.

"I am happy," said Vamal as she left the hospital with her family. "I can walk again -- and there is no pain."

Published on November 1, 2006 in Wired News

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