The chain has so far benefited five local kidney patients. It also marks the first time that 15 transplant centers in the region collaborated so closely. The partnership continues: A sixth donor kidney is potentially awaiting a matched recipient who can step up with a donor.
The idea of a kidney-donation chain may seem complicated, but simpler schemes are not meeting the demand. Today, more than 89,000 people in the United States are waiting for kidneys from the usual source - deceased donors - and more than 4,000 last year died waiting.
More than 5,000 patients are waiting in the Philadelphia region alone, far more than the 767 individual kidney transplants coordinated last year by the Gift of Life Donor Program, the region's federally designated organ-procurement group.
That is where donation chains can make a difference. Transplants work only between people with matching blood types and compatible immune systems. Some patients are harder to match than others and can end up waiting indefinitely.
A chain grows from pairs of people, often spouses or relatives. One needs a kidney. The other is willing to give a kidney, but is not a match. In the past, that would have been the end of the line.
Now, this donor may be considered as a potential match for the patient of a different mismatched pair.
If an outside kidney can be found for his or her original partner, the first donor "pays it forward" by donating a kidney to another stranded pair. The chain continues as long as each donor is still willing to give. The agreement is voluntary.
"It's not a payment situation," which would be illegal, notes bioethicist Arthur Caplan of the University of Pennsylvania. "It's more like a payment in kind."
This give-and-get dynamic can raise unexpected emotional tensions between recipients and the donors who help them enter the chain.
James Crowder, a barber from Pottstown, needed a kidney, and his wife, Rosemaria, was not a match for him. She signed up as a chain donor so that James Crowder could qualify. But after his transplant in January, he feared she might feel obligated to donate.
"I think I maybe would start fights with her," he said, "to give her a way out."
Less than one week before Rosemaria Crowder's scheduled surgery in April, the pair actually separated briefly. Friends and doctors suggested she consider dropping out.
But she never wavered. Having seen her husband benefit, she thought about what her donation would mean for another family.
"I didn't want to go back on my word," Rosemaria Crowder said. "That would have been so selfish of me." The couple reunited on the morning of her surgery.
The mixed feelings of altruism and obligation are reasons that counseling is an important part of the process. Diane James, manager of Gift of Life's living-donation program, said hospital policies have evolved to require living donors to be evaluated by a social worker and assigned an advocate.
The current chain began on Peniazek's surgeon's notepad, but eventually picked up momentum and was taken over by James at Gift of Life. She solicited unmatched pairs from more local transplant centers, which were pooled in a database. Using software from Johns Hopkins University, she pulled out potential biological matches.
Computer-matched pairs then got extensive blood testing. After months of testing, James and Lim, the Lankenau surgeon, assembled a chain of five donor-recipient pairs from across the region.
The first surgery was in December; the last, in May. James hopes to expand the database and entice more centers to join, perhaps enabling the chain to continue.
Many hospitals arrange occasional smaller kidney exchanges on their own, often with out-of-state partners. Our Lady of Lourdes Medical Center in Camden, for example, announced last year that it had participated in a four-way swap with hospitals in northern New Jersey, Boston, and New Hampshire.
The Philadelphia exchange registry is the first to help transplant centers in this region connect their unmatched pairs locally. It is one of several registries around the country, each managed under different rules. Many patients are listed on multiple exchange registries, even as they wait for a deceased donor.
Meanwhile, the federally contracted United Network for Organ Sharing is working on a national kidney-exchange registry that would amass unmatched pairs and operate under a single policy.
Lim doubts that the new exchanges will erase the national shortage anytime soon. Coordination among centers can be difficult, but more important, the number of living donors is simply not enough.
Even rarer are donors like Peniazek who will give to a stranger expecting nothing in return; they accounted for only 204 kidney transplants in the United States last year.
Peniazek hopes that her example will show that kidney donation is safe and easy. Her recipient's insurance covered the minimally invasive surgery, in which her left kidney was removed through a tiny incision.
Three days later, on Dec. 19, Peniazek was home from the hospital with "85 percent strength." She recovered in a few weeks, and now the retired mental-health worker at Norristown State Hospital says all that has changed is that she avoids pain medications such as ibuprofen (which could stress her remaining kidney).
Even if others do not rush to donate, Lim said, any transplant chains at all can only decrease the number of patients in need.
"We already have one altruistic person who in the past would have only helped one patient," he said. "We've turned it into a 5-1 impact."
Contact staff writer Helen Shen at HShen@philly.com