Diseases & Conditions
For people of all ages who have irreversible kidney failure, kidney transplantation is a lifesaving alternative to dialysis. In the United States, more than 17,000 kidneys are transplanted each year. Over 95% of kidneys from living donors are functioning 1 year after transplantation. Three percent to 5% of these kidneys stop functioning each year after the first. About 82 to 91% of kidneys from deceased donors are functioning 1 year after transplantation. Five percent to 8% of these kidneys stop functioning each year after the first. Transplanted kidneys sometimes function for more than 30 years. People with successful kidney transplants can usually lead normal, active lives.
About two thirds of transplanted kidneys come from deceased donors. The kidneys are removed, cooled, and transported quickly to a medical center for transplantation to a person who has a compatible blood and tissue type and who does not make antibodies to the tissues of the donor.
Kidney transplantation is a major operation. The donated kidney is placed in the pelvis through an incision and is attached to the recipient's blood vessels and bladder. Usually, the nonfunctioning kidneys are left in place. Occasionally, they are removed because they are causing uncontrollable high blood pressure or are infected.
Despite the use of immunosuppressants, one or more episodes of rejection may occur after transplantation. Acute rejection can be accompanied by fever, decreased urine production with weight gain, pain and swelling of the kidney, and elevated blood pressure. Blood tests demonstrate deteriorating kidney function. Because these symptoms can also occur with infections or drug toxicity, the diagnosis of rejection can be confirmed with a needle biopsy of the kidney.
Acute rejection occurs within 3 to 4 months of transplantation. It can usually be controlled with high doses of immunosuppressants or antibody therapy given for a short time. Sometimes, using a different drug for maintenance immunosuppression helps control rejection.
Chronic rejection that develops over many months to years is relatively common and causes kidney function to gradually deteriorate. If rejection cannot be controlled, the kidney will fail and dialysis must be started again. The rejected kidney may be left in place unless fever, tenderness, blood in the urine, or high blood pressure persists. The chance of success with second transplants is almost as good as that with first transplants.
Compared with the general population, kidney transplant recipients are 10 to 15 times more likely to develop cancer, probably because the immune system helps defend the body against cancer as well as infections. Cancer of the lymphatic system (lymphoma) is 30 times more common in kidney transplant recipients than the general population, but lymphoma is still uncommon. Skin cancer is common.
Last full review/revision September 2008 by Martin Hertl, MD, PhD; James F. Markmann, MD, PhD; Paul S. Russell, MD; Heidi Yeh, MD
Source: The Merck Manual Home Edition