Below are some of the questions that previously have been posed to Transplant Week, and the answers that were provided by members of the Transplant Week Medical Advisory Board. If you have questions that are not answered below, feel free to submit them via email to editor@transplantweek.org. Answers to questions that are deemed of general interest will be found under the New Questions heading.

May 2001

With almost 50,000 patients now on transplant waiting lists for a cadaver kidney, a growing number of Americans view living donation as their best hope of receiving a transplant. And the big question -- when a family member, relative, friend, co-worker, or even a stranger offers to be a donor -- is will tests show that person to be medically compatible.

Several questions this month focused on medical compatibility issues.

Dr. Joshua Miller, co-director of the University of Miami Transplant Centers, responds to several of these questions.

"I would like to donate a kidney to my wife, but the doctor at the medical center who tested me said the results are best where the recipient and the donor are a six antigen (HLA) match, and he told me I am a zero antigen match for my wife. He said I would not make a good donor for my wife, and recommended that we wait for a cadaver kidney to become available. I thought with all the powerful new anti-rejection drugs, antigen matching was not as critical as it used to be. How important is antigen matching? Are kidney survival rates higher when there is a higher antigen match? -- N.G.

Dr. Miller's reply:

"Those are good questions. I confess that my views are among a conservative minority on this subject. Human Leukocyte Antigen (HLA) matching is important because it is the system used to identify the unique markers (antigens) that the immune system recognizes as either belonging, or not belonging, to your body. You inherit your HLA marking through genes from your parents. You get three of the most common detectible antigens from your mother and three from your father. What everybody will agree on is where there is a six out of six match - which always occurs in identical twins, and occurs one out of four times with a sibling - the outcome has always been significantly better. In cadaver donation, this also appears to hold true. Even where the donor does not have all of the HLA antigens of the recipient, but where none of the identified HLA antigens of the donor are different than those of the recipient, the long-term survival of the kidney also has been significantly better.

"Minimum requirements for HLA matching vary from transplant center to transplant center. During the past few years, many centers have taken the view that antigen matching was less important with living unrelated donors - that the only thing really required was ABO blood-type compatibility between donor and recipient and a negative cross-match (no preformed antibodies in the recipient against the donor). I personally take the minority view that HLA antigen matching is still very important, but the general rationale seems to be that the higher quality of a healthy kidney from a living donor outweighs what is lost from a lower antigen match. A number of variables affect the survival of a transplanted kidney, and the health of the organ that will be transplanted clearly is an important one.

"But I still think that histocompatibility must make a difference in living kidney donation, and a large multicenter study in Europe of living-unrelated pairs recently appeared to confirm this. Most of the effects of histocompatibility these days, however, seem to be more marked years after the transplant. And when one is talking about long-term survival rates for a kidney these days, one is no longer talking about the five-year benchmark of a decade ago. Now, long-term is 10 or 20 years, or even more. So I think the jury is still out on your question."

"Would doctors have to compensate for a poor antigen match by giving my wife increased anti-rejection medication, which could possibly have other adverse health consequences? "

"Most centers start all of their transplant recipients (except for living- related six antigen matched pairs) on a similar protocol of immunosuppressive medication. If there are rejection episodes, adjustments are made. Any increase in dose of these powerful medicines, of course, has potentially negative consequences."

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April 2001

More than 5,000 Americans last year donated one of their kidneys to an immediate family member, relative, friend, co-worker, or even a stranger. Until recently, these donations required an eight to nine inch incision in the donor - an extremely safe process, but one that generally required a six-to-eight week recovery period.

In the past several years, however, a growing number of transplant centers have begun removing the donor kidneys by laparoscopic surgery, a minimally invasive approach involving much smaller incisions.

This approach generally involves less pain, shorter hospitalization, and a rapid return to normal activity. But it is a technically newer operation, and is not yet performed at all transplant centers.

Several questions this month have focused on medical issues surrounding laparoscopic surgery that are very relevant for a person considering being a living kidney donor.

Dr. Joshua Miller, co-director of the University of Miami Transplant Centers, responds to several of these questions.

"Are there any outcome studies relating frequency or other variables to living donor laparoscopic nephrectomies?" - K.S.

Dr. Miller's reply:

"I don't know of any comparative outcome studies between centers yet, but there is always a learning curve, and in general, the more laparoscopic donor nephrectomies that a center has performed, the less chance there is likely to be of unforeseen complications. Another factor would be how much experience surgeons at the hospital have performing other complex laparoscopic procedures. In general, large centers will have more experience than smaller centers. I would think looking for a center that has performed at least 25 laparoscopic donor nephrectomies over the course of a year would not be unreasonable."

"Is there quantitative data available on which medical centers and surgeons have the most experience?"

"There is no comparative data of which I am aware. The University of Maryland Medical Center in Baltimore has the greatest experience with this procedure - having performed several hundred laparoscopic nephrectomies since 1996 - but there certainly are other centers that have had excellent results."

"What are the donor criteria for a laparoscopic nephrectomy?"

"Well, there are a variety of factors doctors will consider. Obesity might argue in favor of an open nephrectomy. Multiple arteries or veins to the kidney are sometimes a consideration. If you are a female donor of child-bearing age, several centers would prefer to have you donate your right kidney, since that kidney is somewhat more likely to be involved in infections during pregnancy (although this is infrequent). That would probably rule out a laparoscopic nephrectomy, since most centers laparoscopically procure the left kidney as the donor organ, primarily because the inferior vena cava - a large vein in the abdomen -- is so close to the kidney on the right side. But approximately nine out of 10 patients considering donating a kidney are candidates for the laparoscopic approach."

"What is a reasonable conversion rate during the procedure from laparoscopic to open?"

"The possibility of running into the unexpected during laparoscopic surgery is not zero, and when that happens, it becomes necessary to convert to an open nephrectomy. I would think this should not occur in more than 5 percent of the laparoscopic nephrectomies performed at a center."

"Is it possible to have a laparoscopic nephrectomy without general anesthesia?"

"At this point, my own answer would be no. But 'possible' is an evolutionary term in medicine."

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March 2001

Several questions this month have focused on the amount of time a patient has to wait for a transplant. Dr. Joshua Miller, co-director of the University of Miami Transplant Centers, responds to one of these questions.

"My doctor (at a medical center in the Northeast) told me I will have to wait more than a year -- and perhaps much longer-- before an organ will be available for my transplant. Can I get a transplant quicker by going to some other center?" -- B.A.

Dr. Miller's reply:

"Possibly. Some medical centers in areas with strong organ donation programs tend to have shorter average waits than those in other areas. But there are a lot of other individual factors -- histocompatibility, blood type, even luck -- that can make the wait for any individual patient at any center either shorter or longer.

"Then there are other considerations that are not often discussed that go into differences in waiting times as well. For example, each transplant center has its own acceptance criteria for donated organs. A center that takes more organs may get you a transplant quicker, but the likelihood that your new organ still will be functioning three years later may not be as good.

"Another consideration you should also carefully consider is the important matter of follow-up care after your transplant. The reality is that situations are going to arise following your transplant where you will need the care of transplant specialists. A medical center 1,000 miles away may have a very different approach to issues that arise than one nearer your home. Long-distance monitoring and care are not easy.

"Instead of worrying about waiting times, I would encourage you to focus on the results achieved by the center, and whether you are comfortable with and have confidence in the transplant team that will be caring for you not just through the surgery -- but for years to come."

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