The ongoing story of Renada Daniel-Patterson's need for a kidney transplant, and her father's offer to donate his only kidney raises questions about the limits of altruism, the risks people will take to benefit their loved ones, and the role medicine should play in establishing those limits.

What's your opinion?

Renada's father, David Patterson, donated one of his kidneys to her in 1996 while he was in a California prison. Renada's body has since begun to reject the transplanted kidney, and now her father has offered to effectively trade places with her by donating his second (and last) kidney. This would require him-instead of Renada--to go on dialysis for the rest of his life, which is a poor substitute for one's own kidneys and carries significant health risks. The case is complicated by the fact that since Mr. Patterson remains in prison, his dialysis would be provided and paid for by the state.

Many people have donated a kidney to a loved one in need of a transplant, but none has ever donated their only kidney. The reason seems clear-we function fine with one kidney, but are chronically ill without any; this is the reason for kidney transplants in the first place. We seem to accept the fact that the kidney donor faces unnecessary health risks so in return the recipient may receive great benefit. But how far are we willing to go in allowing people to bear personal risks for the sole medical benefit of someone else?

Doctors tell stories of parents making serious offers to donate their hearts to a son or daughter needing a transplant. These offers of one's very life to save another are refused, but show the extent to which individuals are willing to go. We just don't view trading one life for another as a medically acceptable alternative.

Taking on some amount of personal risk to help another is acceptable and even cheered--but only up to a point. When a good Samaritan jumps into deep water to save a drowning stranger, we cheer that as heroic. But if the good Samaritan can't swim, we call that rash or foolhardy. Self-sacrifice needs to have the chance of ending well for both parties before we consider endorsing it as a good act.

When a father offers his only kidney to his daughter--after her body has rejected his first kidney--the harm to his health is clear and inevitable, and the benefit to her health is questionable. But even if it were certain to improve Renada's health, acting on her father's decision challenges what society can accept and is certainly more than it can expect from its citizens.

Doctors' roles

Renada's family, including her father, argue that it is their decision and not up to the physicians or the hospital to decide what amounts to a family matter. But in fact physicians must consider what is in the best interests of their patients, and a kidney donor's interests must be considered along with those of the kidney recipient.

Deliberately maiming, or even killing one patient to help or save another cannot be construed as a morally acceptable medical decision, no matter how willing the patients. Trading the health or welfare of one person for another runs counter to our basic societal beliefs about justice and the rights of individuals-for instance we don't allow slavery, even by willing parties.

Only when the risk to the donor is acceptably low and the ill effects likely to be neither life-threatening nor permanent, should we consider allowing acts of pure medical altruism. Mr. Patterson's desire to sacrifice himself by donating his only kidney doesn't qualify on either count, and so his offer to trade places with his daughter should not be accepted.