Health A-Z

Medical Content Created by the Faculty of the
Harvard Medical School

Kidney Transplant

What Is It?

A kidney transplant is surgery in which a person who has permanent kidney failure receives a healthy kidney from another person. This single, healthy kidney takes on the workload of both of the person's failed kidneys. The failed kidneys usually are left in place, and the new kidney is added to the abdomen.

The new kidney can come from a living or dead donor. A living donor usually has to be a close blood relative of the person who receives the new kidney (the recipient). However, in certain cases, a recipient's spouse or friend can be a kidney donor.

A kidney donor must be a good match for the recipient. A good match means that the donor and recipient have similar chemical characteristics, called antigens, located on their body cells. When these chemical characteristics match, there is less risk that the recipient's immune system will see the donor's kidney as a foreign object and reject it.

More than 15,000 kidneys are transplanted each year in the United States. Just under 60% of those transplants use kidneys donated from people who recently died. In the United States, an organization called the United Network for Organ Sharing (UNOS) helps to locate and distribute donor organs.