08/03/12

UK Scientists Develop Revolutionary New Kidney Transplant Procedure

Scientists in the UK have developed a revolutionary new procedure that could dramatically improve the prospects of thousands of renal patients by increasing the success rate and longevity of kidney transplants, while also enabling more organs from marginal donors to be used for transplantation.

The project, funded by national charity Kidney Research UK, is the first of its kind anywhere in the world and has led to the development of a process called normothermic perfusion – a form of resuscitation which allows doctors to improve the quality of kidneys taken from deceased organ donors.

By flushing donor kidneys with oxygenated blood prior to transplantation, normothermic perfusion reverses the damage done to organs by storing them at low temperatures – optimizing early graft function so that they work better immediately after transplantation.

With kidneys that function well early on proven to last longer, it is thought normothermic perfusion could not only reduce rejection rates but also increase the lifespan of transplanted kidneys, which currently only last around 10 to 15 years.

Professor Mike Nicholson, lead researcher for Kidney Research UK, said: “Normothermic perfusion allows us to gradually reintroduce blood flow to donor kidneys outside of the body and in a controlled way.

“This reverses much of the damage caused by cold storage, while offering us a unique opportunity to treat the organs with anti-inflammatory agents and other drugs before going on to complete the transplant procedure.

“In short, we’re able repair and revive damaged kidneys in a way that would otherwise be impossible.”

Early results from the project are extremely encouraging with only one of 17 kidneys treated using normothermic perfusion showing signs of delayed graft function after transplantation.

Delayed graft function is a common feature of kidney transplantation and can significantly compromise the long-term success of a transplant. It is not unusual for delayed graft function to occur in up to 50 per cent of kidney transplants.

Normothermic perfusion also has the potential to expand the organ donor pool and reduce the transplant waiting list by utilising more kidneys from marginal donors – people who have suffered uncontrolled cardiac death, as well as elderly donors and those with diabetes, hypertension or renal insufficiency.

“There’s often great reluctance among health professionals to use kidneys from marginal donors, as there’s no way to establish how much damage has been caused to the organs and whether or not they will work,” explained professor Nicholson.

“As a result, these organs are often discarded as a precaution, rather than taking the risk of using them for transplants.

“Normothermic perfusion allows us to perform a crucial viability check on these kidneys, pumping them with blood to confirm whether or not they function adequately enough to be used for transplantation.”

At present, 90 per cent of all patients on the UK’s transplant waiting list are in need of a kidney, while fewer than 3,000 kidney transplants are carried out each year. With the kidneys of half of all uncontrolled cardiac death donors alone discarded last year, normothermic perfusion could cut the transplant waiting list by more than 10 per cent.

Reducing the transplant waiting list would also have profound implications for the NHS, which spends £3.66 billion of its annual budget on treating kidney failure.

The average cost of keeping a patient on dialysis for one year is currently £30,800, while a full kidney transplant incurs a one off cost of around £42,000 per patient, with maintenance costs of £6,500 per year thereafter. This means the cost benefit of kidney transplantation compared to dialysis over a period of ten years is £241,000 per patient, or £24,100 for each year a patient’s kidney continues to function.

Charles Kernahan, Chief Executive of Kidney Research UK, said: “This project represents a major step in the fight against kidney disease. Although transplantation is by no means a cure for kidney failure, it is by far the best treatment method available to us at this time.

“In developing a process that not only maximises the quality of kidneys taken from marginal donors but could also lead to hundreds more transplants being carried out each year, our researchers have given fresh hope to the 7,000 people in the UK currently waiting for a kidney.”

The Charity is now appealing for increased funding for renal research in order to take normothermic perfusion on to clinical trials. For more information about kidney disease and the work being undertaken by Kidney Research UK, please visit: www.kidneyresearchuk.org.