BOSTON (AP) _ Transplanted kidneys imperfectly matched to recipients fail more often in the first year when they have been shipped long distances, a study found.
The researchers tied the greater risk to the longer time the organs spent in cold storage during shipment.
University of Pennsylvania researchers led by Dr. Kevin C. Mange looked at 5,446 pairs of kidneys collected from dead donors. In each case, one of the donor's kidneys was transplanted locally, and the other went to a patient in another region.
The findings, published in Thursday's New England Journal of Medicine, showed a 17 percent higher failure risk in the first year for the organs that were shipped long distance.
There was no difference in risk when transplanted kidneys were perfectly matched to the recipient's immune system.
The researchers said their results suggests that in some cases, it might be more important to wait for a better match if the organ has to travel long distance.