(Inside Science) -- In June, my wife, Joanne, and I celebrated a somewhat unusual occasion: the 10th anniversary of her second kidney transplant.
The unusual nature of the celebration stemmed from the origin of the new kidney: I donated it. And no, Joanne and I are not close, or even distant, cousins.
The contrast between Joanne's first transplant, which she had received from her mother 16 years earlier, and the second illustrates how the evolution of medical technology has facilitated live organ donation, thereby opening up the process to a far larger group of donors.
First, my donated kidney has performed better than my mother-in-law's, the decline of which required the second transplant. Ten years after that operation, semi-annual blood and urine tests indicate that the kidney continues to function as well as ever.
Second, my mother-in-law had to undergo a long series of tissue-typing tests to check that her organ would match my wife's system with a minimal risk of rejection. My tests were much simpler.
And after the operation to remove her kidney, my mother-in-law had an 18-inch scar beneath her ribs from the removal of her kidney. My own procedure left me with three small spots on my skin that are all but invisible today.
"Both donors and patients are in better shape as a result of the advances," said Stephen Tullius, chief of the Division of Transplant Surgery at Brigham and Women's Hospital in Boston, who implanted my wife's second kidney.
Easier and Less Painful Transplants
The technical improvements played out before, during, and after surgery.
The entire process "has really developed into a collaborative effort, including input from various disciplines," Tullius said.
In the pre-operative phase, simpler methods have emerged for identifying unrelated donors, who may be spouses, friends, colleagues or even strangers, connecting them with potential recipients, and testing them for their suitability to donate.
The operative procedure has also evolved, Tullius said, to include better equipment and anesthesia.
Donors' post-operative pain has also been reduced by the use of laparoscopy. Otherwise known as keyhole surgery, this procedure removes the kidney without the long incision usually associated with major surgeries.
"The approach really revolutionized the donor approach, because of minimal invasiveness," Tullius explained.
And after surgery, new approaches to immunosuppression -- the reduction in the organ recipient's natural immune system to reduce the risk that the recipient will reject the foreign organ -- have improved the chances of success for kidneys from donors who are unrelated to the patient.
"Immunosuppression certainly has gotten more refined in the way we can apply it," Tullius continued.
One example is the replacement of the old anti-rejection drug Cyclosporin with a new drug, called Prograf and first approved for use in 1994, as part of the cocktail intended to suppress the recipient's immune system.
Even with the relative ease of modern transplants, modern transplantation teams don't ignore the social aspects of the procedure. Potential donors meet several members of an evaluation team assigned to them individually. The team's assignment: ensuring that the donor has decided to donate without pressure and without bias.
Making More Organs Available
The advances have come at a time of growing need for transplanted kidneys and other organs subject to live donation, such as lungs, parts of the liver or pancreas, and bone marrow.
At present, according to the National Kidney Foundation, the waiting list for organ transplants contains more than 100,000 individuals in the United States. The list grows by more than 3,000 each month. And on average, 13 Americans die each day because of the lack of an available kidney for transplantation.
Plainly, the number available for donation falls far short of need.
In 2014, the latest year for which figures are available, surgeons transplanted 17,107 kidneys. Of those, 11,570 came from 7,761 deceased donors (who can provide both their kidneys) and 5,537 from living individuals.
Organs from living donors have some obvious advantages over those from deceased individuals.
First, they allow transplant teams plenty of time to test their compatibility with recipients' bodies. Surgeons can take an organ from a living donor on their own schedule rather than rushing to react to one made available when an individual dies.
Second, a kidney from a living donor usually starts functioning immediately on implantation. That's because it spends very little time outside the body. The operating rooms for donor and recipient are usually side by side.
The process of living donation starts with a check on blood type. A match with the potential recipient sends the donor to the next stage of tissue typing and cross-matching. This consists of blood tests for more detailed checks of the similarities between the recipient and potential donor.
"The closer the match," states the National Kidney Foundation on its website, "the lower the likelihood of rejection of the transplanted kidney."
A Test of Marital Compatibility
My wife's first transplanted kidney showed no signs of rejection. But its performance, measured by blood tests, started to decline after a dozen years.
Since I had read about successful kidney exchanges among loving, long-married couples, I suggested myself as the next donor. When the decline of Joanne's transplanted organ worsened, we started the procedure for her next kidney.
The initial test of a matching blood group proved simple. My group is O, the universal donor.
Then came the blood tests -- and a chest X-ray, an angiogram, an MRI, and a complete physical examination. An interview with a social worker served to ensure that I was "committed to the donation process" and was doing so for altruistic reasons without mental or physical coercion.
The operation to remove my kidney was simpler than my mother-in-law's had been because the surgeon, Sanjaya Kumar, used the laparoscopy instead of the traditional "open" approach.
"Prior to 1995, all kidneys were removed via the open operation; there was no other way to get them," Kumar explained. "These flank incisions are painful because you have to cut through a lot of muscle, at the risk of herniation." In laparoscopic surgery by contrast, "we just split the muscles, not cut them, so there's little pain and little chance of herniation," he continued.
The approach is remarkably simple.
"We make a little incision and put in our hand -- a great instrument to feel tissues, check the range of motion, and facilitate surgery," Kumar said.
The process has a particular advantage in the choice of kidney to remove.
"With the open technique, we took only the left kidney, because it has a longer vein," Kumar said. "But our approach is to leave the better kidney with the donor. If your left kidney is the better functioning one, we should be able to leave it if we operate laparoscopically."
I still have my left kidney. And ten years later, the right-hand one is still serving Joanne well.
Living With One Kidney
I don't want to be too Pollyannaish about the process. Some living donor transplants fail, and a small number of donors can suffer health problems after their operations.
But most individuals can live normal lives with a single kidney, which increases in size after removal of its donated companion. For example, my mother-in-law died this year at the age of 96, 26 years after donating my wife's first transplanted kidney even before many of the recent advances in transplant surgery.
And the advances continue. Surgeons at Johns Hopkins University School of Medicine in Baltimore have developed a process of "desensitization" that reduces recipients' tendency to reject transplanted kidneys. The method, reported in the New England Journal of Medicine in March, filters antibodies from the patient's blood and replaces them with different antibodies while the body's immune system regenerates.
Meanwhile, potential donors who don't match their intended recipients can join a paired kidney exchange program. That approach allows an individual to donate a kidney to a patient who does match in exchange for a donation from another person who does match. Sometimes transplant teams are able to arrange chains that match several donors and recipients.
Technology has opened the way for easier, less painful organ donations. Based on my own experience, I hope that the advances will encourage more donors to step forward to reduce the long lists of patients awaiting transplants.