Four recipients of rare heart-lung-kidney transplants in Chicago are urging people to register as organ and tissue donors.

At a news conference on Wednesday, the four University of Chicago Medicine patients who received the triple-organ transplants in the last year appeared to underline the grim reality that 20 people a day die in the United States waiting for transplants and stand as a testament to the fact that even the most complex transplant operations are successful.

At the University of Chicago's hospital, a total of 10 people have been triple-organ recipients. Eight are still alive.

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