Last year, Johns Hopkins doctors performed a triple transplant also involving an altruistic donor. The donor was from a Christian group, many of whose members have given kidneys to strangers.

Annie Moore, a spokeswoman for the United Network for Organ Sharing, the nonprofit organization that coordinates U.S. organ transplants, said she wasn't aware of any other quintuple kidney transplants. Triple transplants are the biggest that have been performed up to now, and paired transplants are more common, Moore said.

Most kidney transplants use organs taken from cadavers, but doctors prefer organs from live donors because the success rates are higher.

In a live-donor practice used increasingly in the U.S. over the past few years, a patient who needs a kidney is matched up with a compatible stranger if the patient lines up a friend or relative willing to donate an organ to a stranger, too.

About 16,500 kidney transplants were performed in the United States in 2005, of which about 10,000 involved organs taken from dead people and 6,500 from living donors, according to the Organ Procurement and Transportation Network.

About 70,000 people are waiting for a kidney transplant in the United States. The wait averages about five years, during which time 30,000 will either die or become too sick for a transplant, Montgomery said.

Montgomery called for a national kidney-swap program, saying it could help ease the shortage of transplant organs and cut costs by getting people off dialysis. He said 6,000 people on the waiting list for a kidney from a dead person have a willing but incompatible donor.

He noted, however, that live-donor kidney swaps present ethical problems for some institutions since federal law prohibits receiving something of value in exchange for an organ. Some institutions feel multiple arrangements come uncomfortably close to quid pro quo, Montgomery said. He called for a clarification of the law.

The complicated swap worked this way:

Rothstein donated her kidney to Jantzi. Jantzi was incompatible with the kidney offered by her adoptive mother, Florence Jantzi, a Christian missionary who donated her kidney to George Brooks, 52, a mechanic who was not compatible with the kidney offered by his wife, Sharon Brooks.

Sharon Brooks, 55, a telephone company maintenance administrator, donated her kidney to Gary Persell, 61, a retired film distributor. His wife, Leslie, 61, a retired history teacher, gave her kidney to Gerald Loevner, 77, a real estate developer. Loevner's wife, Sandra, gave a kidney to Sheila Thornton, a retired elementary school teacher.