A British woman has undergone a life-saving kidney transplant after having her blood plasma frozen and filtered to ensure that the organ was not rejected. Maxine Bath, 41, is the first person in the world to have the groundbreaking operation, which allowed her to receive an "incompatible" donor kidney from her sister despite having dangerously low blood pressure.

Ms Bath, who had been on dialysis for 15 years after kidney failure, waited a decade for a kidney that would not trigger tissue rejection by her body. Doctors feared that she had only months to live after developing blood pressure problems over the past year.

The operation, carried out at University Hospital in Coventry at the end of November, involved the use of a cryofiltration system to remove plasma from the blood and chill it, turning proteins and antibodies into a gel-like substance.

This allowed the antibodies, which can prevent a transplanted organ from being accepted, to be filtered away before the plasma was warmed up and returned to the patient.

Rob Higgins, a renal consultant, told The Times that it was the first time the technique had been used in a tissue incompatible transplant. He added that it had been essential because other antibody-removal procedures would have lowered Ms Bath's blood pressure even further.

The family of Ms Bath, from Wolverhampton, was tested ten years ago to see if any were suitable donors but none was compatible.

A total of 927 kidney transplants from living donors were carried out in Britain last year - more than one in three of all kidney transplants - but thousands more remain on waiting lists. About a quarter of patients requiring kidney transplants have some antibody against other people's tissue types.

Among the members of Ms Bath's close family, it was her younger sister, Michelle Titmus, who was the closest match. Both sisters had five sessions of cryofiltration before Ms Bath was able to receive a kidney from her sister.

Dr Higgins, of University Hospitals Coventry and Warwickshire NHS Trust, said that the technique offered the potential to carry out life-saving operations on many more people who would otherwise be ineligible due to rejection and blood pressure problems. "This is an innovative measure we have implemented at the trust which opens the doors of donation for more kidney patients awaiting transplants," Dr Higgins said.

"If Maxine had carried on with dialysis her chances were pretty slim." He added that had she survived further dialysis, she would have gone blind because of her low blood pressure. The number of people with severe kidney disease that require dialysis and transplantation is increasing in all western societies, mostly because of the increase in diabetes and ageing populations. In some cases replacement plasma is used, rather than cryofiltration, but this is not always tolerated and can produce further drops in blood pressure.

Ms Bath said that after completing six months of rehabilitation she had a job as a cleaner lined up. "Although it's not been long since I had the operation I'm already feeling healthier," she said.

"I am looking forward to being able to eat food I couldn't have at all before like nuts and chocolate. I just want to get back to a normal life."

Mrs Titmus, of Kingstanding, Birmingham, said that it had been heartbreaking to see her sister's health declining. "knowing there wasn't anything we could do to help her".

"It's been very difficult to see Maxine getting slowly worse over the last few years," she said. "It may sound silly but it really hits home when I can watch her eat food that could have killed her before, like a jacket potato."

Mrs Titmus, 40, will return to her job as an office worker after three months of recuperation.

Chris Rudge, the Department of Health's national clinical director of transplantation, said that the technique was a valuable extension of continuous research into how to transplant kidneys from living donors in circumstances where the recipient had antibodies.

He said that although the number of patients that would benefit would not be large, it was to be welcomed. "Traditionally [antibodies] would mean that a transplant was not possible but there is an increasing range of methods being used to remove the antibodies and so allow the transplantation to go ahead," he said.

"While the technique may apply to a limited number of patients, to the individual, if it makes the difference between no transplant and a transplant, then it's hugely important."