Winning over hearts, minds and kidneys

Canada looks for new ways to work with its organ stocks

By Jason Gondziola

Currently, Canada produces only 14.5 donors per million residents, according to Dr Arvind Koshal, director of cardiac surgery at the Alberta Heart Institute.

"I think we have more work to be done in that area," he says. "We do need much more awareness, and also commitment."

The numbers are low, and a flat donors-per-million statistic doesn't take into account the types of death that occur from area to area, according to Michael Bloch, a donor coordinator at the London Health Sciences Centre.

"Right now... only 2 to 3% of all the deaths that occur could be seen as possible organ donors," he says. "It's very few to begin with."

WASTE NOT, WANT NOT
Despite the shortage of donors, Canadian transplant units are creatively using what they've got and exploring new technologies.

"As far as the technology is concerned, programs find that they have to resort to � I wouldn't call them desperate measures � but extended measures in utilizing what we term marginal donors," says Mr Bloch.

Marginal donors are those who might not be used under better circumstances. Bloch gives the example of a 70-year-old kidney donor. While the donor's kidneys might not run at the same clip as a 30-year-old's, surgeons can implant both of them in a recipient's body. In tandem, the two older kidneys can do the work of one younger one.

THE BEAST IN ME
But why limit ourselves to humans? An experimental process known as xenotransplantation is looking for solutions outside the species. Unfortunately, using organs from other animals is a very tricky affair, and despite extensive research throughout the entire 20th century, xenotransplantation has yet to clear the high hurdle of rejection. Plus, there are other risks inherent in the practice, says Dr Koshal, who served as an expert advisor on the National Forum on Xenotransplantation.

"I think the main problem has been the possibility of transfer of infection through animal organ to humans," he says. "That has set this program back considerably."

With the fear of mad cow disease and avian flu lurking in the air, Dr Koshal feels that it's "very unlikely" that these programs will see clinical use any time soon.

ISLETS IN THE STREAM
A more immediately promising avenue of research focuses on a donor's islet cells, the pancreatic cells that produce insulin. "Rather than a transplant, it's almost done like a transfusion," explains Mr Bloch. "You don't really need the pancreas as such; you just need the cells."

The London Health Sciences Centre is currently setting up an islet cell transplant lab � the third of its kind in Canada. The procedure requires a donor pancreas, which technicians subject to an enzymatic digestive process. The end result is a solution of islets. In an interesting twist, the islet cells are not injected into the pancreas of the recipient patient, but into their liver, which has a widely spaced vascular system. The cells then stick to the inside of the liver and remain there, producing insulin.

"The objective is not necessarily to take people off insulin therapy," says Mr Bloch, who adds that the patients who are treated with this procedure are usually very unstable diabetics. The new islet cells serve to normalize the patient's insulin levels to a controllable level.

The procedure currently takes between six to eight hours, at a cost of $10,000 per pancreatic isolation, plus surgical costs.