An extra 1,000 transplants could be done every year, Johns Hopkins study suggest.
An additional 1,000 patients could
undergo kidney transplants in the United States annually if hospitals
performed more transplants using paired kidney exchanges, new Johns
Hopkins research suggests.
Also known as
kidney chains, paired kidney exchanges, which allow incompatible donors
to give a kidney on a loved one’s behalf and ensure that loved one gets a
compatible kidney from a third party - usually a stranger - in
return, have become much more common since 1999 when The Johns Hopkins
Hospital pioneered the practice. But the dramatic growth in the use of
these exchanges - from 93 transplants in 2006 to 553 in 2010 - has now
stalled, primarily because of financial barriers related to logistics,
administrative costs and insurance coverage for donors, researchers say.
A report on the research appears online in the American Journal of Transplantation.
are more than 100,000 people waiting for a kidney transplant in the
United States. For the one-third of patients who manage to find a living
donor but learn they are the wrong blood type or are otherwise
incompatible, kidney exchanges offer a very high rate of successful
transplantation," says study leader Dorry L. Segev, M.D., Ph.D., an
associate professor of surgery and epidemiology at the Johns Hopkins
University School of Medicine. "But many transplant centers have not
found a way to make this possible for their patients."
success of kidney chains depends on the best possible matches, and
these depend in turn on the largest possible pool of transplant
candidates and their incompatible donors. With more centers
participating, Segev says, more matches can be found and more
transplants can be done.
found that between January 2009 and December 2011, while 161 transplant
centers (77 percent of the 207 in the United States) performed at least
one transplant through a kidney exchange, most were performing fewer
than would be expected. In fact, more than 50 percent of all exchanges
and chains were concentrated in only 22 centers. The largest number
performed at a single center was 137. "If every center performed
exchanges at the same rate as the top centers, an additional 1,099
transplants could take place annually," says Allan B. Massie, Ph.D., one
of the researchers involved in the study.
biggest barrier to increased paired exchange and chain transplants,
Segev says, is that there is no consistent or reliable entity, either
within or outside institutions, paying the extra expenses associated
with kidney exchanges, which require personnel and time spent making
matches, coordinating logistics among various centers, and quickly
shipping organs across town or across the country, to wherever the
patient in need is located. In addition, there is no standard way for
insurance companies to determine which company pays for which donor’s
Segev notes that some centers
regularly perform two- and three-way transplants. In 2009, Johns Hopkins
performed an eight-way, multi-hospital kidney transplant, which
involved an altruistic donor and seven pairs of people -- each made up
of one person in need of a kidney and one willing but incompatible
"At this point, every center in
the country has the logistical and intellectual ability to do these
exchanges," says Segev, director of clinical research for transplant
surgery at Johns Hopkins and co-developer of one of the first computer
algorithms that make exchanges possible. "Over 75 percent of centers
have performed at least one kidney exchange transplant over the past
three years, suggesting that most of the limitation is not a willingness
to participate but rather financial and support service barriers."
Few hospitals used kidney exchanges until Johns Hopkins researchers in 2005 published a paper in the Journal of the American Medical Association
showing the extent to which patients could benefit from the procedure.
Several regional databases of transplant patients and their incompatible
donors have been developed in recent years, offering the potential for
even more transplants if more patients and donors enter the mix.
patients awaiting transplants remain unaware of exchanges, Segev
believes. Patients need to ask to participate. The waiting list for
kidneys from deceased donors is three to five years and can be up to 10
years in some regions of the country. And 5 to 15 percent of patients on
dialysis die every year waiting for a transplant. Having a kidney from a
living donor means a patient can undergo transplantation without
waiting in line for a deceased donor transplant.
exchanges have done a lot of good," Segev says. "But we could do three
times as much good if more centers did more of them."
study was supported by grants from the National Institutes of Health’s
National Institute of Diabetes and Digestive and Kidney Diseases (RC1
DK086731) and the Charles T. Bauer Foundation.
Other Johns Hopkins researchers involved in the study include Sommer E. Gentry, Ph.D., and Robert A. Montgomery, M.D., D.Phil.
Source: Johns Hopkins