Risks and Benefits to the Living Donor
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《新英格兰医药杂志》
In the five decades since the first renal transplantation from a living donor took place, in 1954, donating a kidney has become common; according to the Organ Procurement and Transplantation Network, 6647 people became living kidney donors in the United States in 2004. Indeed, donating a kidney is sufficiently safe that the emotional benefits to the donor generally far outweigh the risks. During my career as a pediatric nephrologist, I have discussed kidney donation with scores of potential donors, helping the transplantation team to explain to the potential recipient and donor the procedure and its associated risks and benefits. In fact, I feel certain that I would be willing to donate a kidney, should a family member or intimate friend need one.
Antonia Reeve/Getty Images.
Advances in immunosuppression have changed the criteria for donation of a kidney by a living person, and someone who is neither a relative of the recipient nor a close HLA match can now donate. Increasing numbers of transplantations from unrelated donors are now being performed (raising many ethical issues that are addressed by Steinbrook and Truog in this issue of the Journal, pages 441–444 and 444–446, respectively), and recipients are increasingly likely to receive a transplant that functions well for many years. But what are the risks to the donor? Nowadays, the risks — both physical and emotional — associated with kidney donation are more completely understood than they were in the early years of transplantation; some of the risks were unanticipated.1
Although donating may be an emotional necessity when the recipient is the donor's child, spouse, sibling, parent, or other loved one, this is far less likely to be the case for friends or anonymous donors. The current criteria for donor suitability now permit selected persons who have medical conditions such as treated hypertension to donate. Therefore, predonation evaluation assumes greater importance, since donors will undergo an operative procedure that is otherwise unnecessary yet can present medical hazards. The team evaluating a potential donor should not be the same as the team evaluating the recipient, given the obvious conflicts of interest.
Before kidney donation, a number of physiological studies must be performed to establish that the donor is in excellent health and has normal renal function and that the anatomy of the kidney is suitable for transplantation. In 1954, the kidney transplantation between the Herrick twins was performed without vascular imaging of the donated kidney, because at that time arteriography involved greater risk than surgery itself. Imaging of the renal vasculature has since evolved and is now standard procedure before kidney donation. It may identify unsuspected vascular disease and thereby benefit the potential donor, or it may uncover anatomy that renders transplantation technically difficult. Adverse events, however, are always possible whenever contrast material is used, although newer imaging methods, such as three-dimensional computed tomography and magnetic resonance angiography, mean that exposure to contrast medium is minimal for most donors.
In addition to assessing the appropriateness of the donor's kidney for the recipient, it is important to determine that the loss of a kidney would not pose a short- or long-term threat to the donor's general health. Thus, potential donors with conditions such as hypertension, vascular disease, and the like are generally declined. And donors who are overweight or have certain lifestyle-related problems (e.g., excessive alcohol use) must address these issues successfully before they can donate a kidney. Persons with cancer or certain infectious diseases are excluded from donating, and other conditions, such as renal stones or previous urinary tract infections, may be relative contraindications.
Some conditions once thought to pose little risk to donors are now considered relative contraindications to donation. In X-linked hereditary nephritis, for example, renal failure generally develops in affected male family members, but females, who are carriers of the disease, usually have only microscopic hematuria and may wish to donate a kidney to a brother with renal failure. Although such a carrier will generally remain well when she has two kidneys, her risk of progression of the disease will increase if she loses or donates a kidney and is later subject to common life stresses such as pregnancy.
In addition to the team members who undertake the physical evaluation, transplantation teams generally include a psychiatrist who interviews potential donors to assess their motivation, who examines with them the psychosocial issues involved, and who supports them as they decide whether in fact to donate. The psychological implications of donation must be explored in depth, and there may be psychiatric reasons for declining someone's offer to donate.
What are the risks associated with donating? The short-term physical risks are generally small.2,3 Although on rare occasions renal donors have died, the death rate is 0.03 percent — similar to or lower than that for any operation involving the use of general anesthesia. Other short-term risks are obvious: the risk of bleeding during or after the procedure and the risks of infection or other immediate problems related to the operation. In addition, donors will lose time from work. It can take a few weeks to recover fully from surgery, although the increasing use of laparoscopic donation means that a donor may now be discharged from the hospital in just a few days. Most return to work within four or five weeks.
Long-term health risks are less apparent. Most people do well with a single kidney. Donors may even live longer than nondonors, although this observation may simply reflect the careful selection of living donors from among very healthy candidates.
But long-term risks are not the same for every donor. Kidney function normally declines with age, and kidney donors have an age-related decline in renal function consistent with that observed in the general population. Renal failure has gradually developed in a small proportion of donors, and according to the United Network for Organ Sharing, 56 of more than 50,000 previous kidney donors have ultimately been listed for transplants themselves.1 Although hypertension has developed in some donors over time, hypertension is so common in the developed world that ascribing it to kidney donation is probably not warranted. Occasionally, microalbuminuria develops in donors, and it is worth considering whether renoprotective therapy might be tailored to prevent this complication.
The decision to donate a kidney is inherently emotional. When all goes well, the donor almost always benefits. But what of the emotional stress that can occur when donation fails? A family friend donated a kidney to her brother some 20 years ago, and the kidney failed immediately because of unanticipated hyperacute rejection, for which no treatment was yet available. My friend was devastated, and it took many months for her emotional equanimity to be restored, although her physical recovery was rapid. Nevertheless, she remained glad throughout that she had donated, saying, "I did everything I could for my brother, and I would do it again."
What of donors in whom a physical illness subsequently develops that eventually results in progressive renal failure? More than 25 years ago, I had a teenage patient with end-stage renal disease who received a kidney from his mother, then in her early 40s. The recipient died a few years later. His mother had been deemed to be in perfect health and had no known risk factors for renal disease. Subsequently, she developed insulin-requiring diabetes, which became complicated by nephropathy, peripheral vascular disease, and peripheral neuropathy. She was close to requiring care for end-stage renal disease when she had a fatal myocardial infarction. Despite all her health problems, my patient's mother had remained steadfast in her belief that donating her kidney, which had extended her son's life by a number of years, had been "more than worth it." And indeed most donors, when asked, claim that they would do it all again.4
But is it always worth it, physically and emotionally, to be a donor? And who should decide? Some transplantation programs inform potential donors, on their Web sites and in their informational material, that donation is relatively safe; others do not. Web sites such as Living Donors Online (www.livingdonorsonline.org/kidney/kidney.htm) and that of the National Kidney Foundation (www.kidney.org/recips/livingdonors/) provide information about donation by living persons and generally encourage people to consider it, while also posting reports of the experiences of donors, not all of which are entirely positive.
Fifty years ago, the first transplantation team suggested that organs from living donors should be used only when the likelihood of success for the recipient was high, the risk to the donor was low, and true voluntary consent was obtained from all involved; the Live Organ Donor Consensus Group has largely supported this viewpoint.5 This triple principle is still the standard of care and should remain so. The changes in the chances of success, however, have altered the landscape. It is our responsibility as physicians to ensure that, in an era with shifting criteria, we do not stretch the ethics involved in assessing the risks and benefits to the donor.
References
Delmonico F. A report of the Amsterdam Forum on the Care of the Live Kidney Donor: data and medical guidelines. Transplantation 2005;79:Suppl 6:S53-S66.
Fehrman-Ekholm I, Duner F, Brink B, Tyden G, Elinder CG. No evidence of accelerated loss of kidney function in living kidney donors: results from a cross-sectional follow-up. Transplantation 2001;72:444-449.
Matas AJ, Bartlett ST, Leichtman AB, Delmonico FL. Morbidity and mortality after living kidney donation, 1999-2001: survey of United States transplant centers. Am J Transplant 2003;3:830-834.
Fehrman-Ekholm I, Brink B, Ericsson C, Elinder CG, Duner F, Lundgren G. Kidney donors don't regret: follow-up of 370 donors in Stockholm since 1964. Transplantation 2000;69:2067-2071.
Abecassis M, Adams M, Adams P, et al. Consensus statement on the live organ donor. JAMA 2000;284:2919-2926.(Julie R. Ingelfinger, M.D)
Antonia Reeve/Getty Images.
Advances in immunosuppression have changed the criteria for donation of a kidney by a living person, and someone who is neither a relative of the recipient nor a close HLA match can now donate. Increasing numbers of transplantations from unrelated donors are now being performed (raising many ethical issues that are addressed by Steinbrook and Truog in this issue of the Journal, pages 441–444 and 444–446, respectively), and recipients are increasingly likely to receive a transplant that functions well for many years. But what are the risks to the donor? Nowadays, the risks — both physical and emotional — associated with kidney donation are more completely understood than they were in the early years of transplantation; some of the risks were unanticipated.1
Although donating may be an emotional necessity when the recipient is the donor's child, spouse, sibling, parent, or other loved one, this is far less likely to be the case for friends or anonymous donors. The current criteria for donor suitability now permit selected persons who have medical conditions such as treated hypertension to donate. Therefore, predonation evaluation assumes greater importance, since donors will undergo an operative procedure that is otherwise unnecessary yet can present medical hazards. The team evaluating a potential donor should not be the same as the team evaluating the recipient, given the obvious conflicts of interest.
Before kidney donation, a number of physiological studies must be performed to establish that the donor is in excellent health and has normal renal function and that the anatomy of the kidney is suitable for transplantation. In 1954, the kidney transplantation between the Herrick twins was performed without vascular imaging of the donated kidney, because at that time arteriography involved greater risk than surgery itself. Imaging of the renal vasculature has since evolved and is now standard procedure before kidney donation. It may identify unsuspected vascular disease and thereby benefit the potential donor, or it may uncover anatomy that renders transplantation technically difficult. Adverse events, however, are always possible whenever contrast material is used, although newer imaging methods, such as three-dimensional computed tomography and magnetic resonance angiography, mean that exposure to contrast medium is minimal for most donors.
In addition to assessing the appropriateness of the donor's kidney for the recipient, it is important to determine that the loss of a kidney would not pose a short- or long-term threat to the donor's general health. Thus, potential donors with conditions such as hypertension, vascular disease, and the like are generally declined. And donors who are overweight or have certain lifestyle-related problems (e.g., excessive alcohol use) must address these issues successfully before they can donate a kidney. Persons with cancer or certain infectious diseases are excluded from donating, and other conditions, such as renal stones or previous urinary tract infections, may be relative contraindications.
Some conditions once thought to pose little risk to donors are now considered relative contraindications to donation. In X-linked hereditary nephritis, for example, renal failure generally develops in affected male family members, but females, who are carriers of the disease, usually have only microscopic hematuria and may wish to donate a kidney to a brother with renal failure. Although such a carrier will generally remain well when she has two kidneys, her risk of progression of the disease will increase if she loses or donates a kidney and is later subject to common life stresses such as pregnancy.
In addition to the team members who undertake the physical evaluation, transplantation teams generally include a psychiatrist who interviews potential donors to assess their motivation, who examines with them the psychosocial issues involved, and who supports them as they decide whether in fact to donate. The psychological implications of donation must be explored in depth, and there may be psychiatric reasons for declining someone's offer to donate.
What are the risks associated with donating? The short-term physical risks are generally small.2,3 Although on rare occasions renal donors have died, the death rate is 0.03 percent — similar to or lower than that for any operation involving the use of general anesthesia. Other short-term risks are obvious: the risk of bleeding during or after the procedure and the risks of infection or other immediate problems related to the operation. In addition, donors will lose time from work. It can take a few weeks to recover fully from surgery, although the increasing use of laparoscopic donation means that a donor may now be discharged from the hospital in just a few days. Most return to work within four or five weeks.
Long-term health risks are less apparent. Most people do well with a single kidney. Donors may even live longer than nondonors, although this observation may simply reflect the careful selection of living donors from among very healthy candidates.
But long-term risks are not the same for every donor. Kidney function normally declines with age, and kidney donors have an age-related decline in renal function consistent with that observed in the general population. Renal failure has gradually developed in a small proportion of donors, and according to the United Network for Organ Sharing, 56 of more than 50,000 previous kidney donors have ultimately been listed for transplants themselves.1 Although hypertension has developed in some donors over time, hypertension is so common in the developed world that ascribing it to kidney donation is probably not warranted. Occasionally, microalbuminuria develops in donors, and it is worth considering whether renoprotective therapy might be tailored to prevent this complication.
The decision to donate a kidney is inherently emotional. When all goes well, the donor almost always benefits. But what of the emotional stress that can occur when donation fails? A family friend donated a kidney to her brother some 20 years ago, and the kidney failed immediately because of unanticipated hyperacute rejection, for which no treatment was yet available. My friend was devastated, and it took many months for her emotional equanimity to be restored, although her physical recovery was rapid. Nevertheless, she remained glad throughout that she had donated, saying, "I did everything I could for my brother, and I would do it again."
What of donors in whom a physical illness subsequently develops that eventually results in progressive renal failure? More than 25 years ago, I had a teenage patient with end-stage renal disease who received a kidney from his mother, then in her early 40s. The recipient died a few years later. His mother had been deemed to be in perfect health and had no known risk factors for renal disease. Subsequently, she developed insulin-requiring diabetes, which became complicated by nephropathy, peripheral vascular disease, and peripheral neuropathy. She was close to requiring care for end-stage renal disease when she had a fatal myocardial infarction. Despite all her health problems, my patient's mother had remained steadfast in her belief that donating her kidney, which had extended her son's life by a number of years, had been "more than worth it." And indeed most donors, when asked, claim that they would do it all again.4
But is it always worth it, physically and emotionally, to be a donor? And who should decide? Some transplantation programs inform potential donors, on their Web sites and in their informational material, that donation is relatively safe; others do not. Web sites such as Living Donors Online (www.livingdonorsonline.org/kidney/kidney.htm) and that of the National Kidney Foundation (www.kidney.org/recips/livingdonors/) provide information about donation by living persons and generally encourage people to consider it, while also posting reports of the experiences of donors, not all of which are entirely positive.
Fifty years ago, the first transplantation team suggested that organs from living donors should be used only when the likelihood of success for the recipient was high, the risk to the donor was low, and true voluntary consent was obtained from all involved; the Live Organ Donor Consensus Group has largely supported this viewpoint.5 This triple principle is still the standard of care and should remain so. The changes in the chances of success, however, have altered the landscape. It is our responsibility as physicians to ensure that, in an era with shifting criteria, we do not stretch the ethics involved in assessing the risks and benefits to the donor.
References
Delmonico F. A report of the Amsterdam Forum on the Care of the Live Kidney Donor: data and medical guidelines. Transplantation 2005;79:Suppl 6:S53-S66.
Fehrman-Ekholm I, Duner F, Brink B, Tyden G, Elinder CG. No evidence of accelerated loss of kidney function in living kidney donors: results from a cross-sectional follow-up. Transplantation 2001;72:444-449.
Matas AJ, Bartlett ST, Leichtman AB, Delmonico FL. Morbidity and mortality after living kidney donation, 1999-2001: survey of United States transplant centers. Am J Transplant 2003;3:830-834.
Fehrman-Ekholm I, Brink B, Ericsson C, Elinder CG, Duner F, Lundgren G. Kidney donors don't regret: follow-up of 370 donors in Stockholm since 1964. Transplantation 2000;69:2067-2071.
Abecassis M, Adams M, Adams P, et al. Consensus statement on the live organ donor. JAMA 2000;284:2919-2926.(Julie R. Ingelfinger, M.D)