Kidney Transplant

Alternate Names
renal transplant
transplantation of the kidney



Definition of Kidney Transplant

Kidney transplantation involves placing a healthy donated kidney into a person whose own kidneys have stopped working. The donor kidney can either come from someone who has died (formerly called a "cadaveric" donation) or from a living donor, often a blood relative.

Who is a candidate for the procedure?

Only people who have complete and irreversible kidney failure are candidates for this procedure. Before the transplant, their kidney function is usually being handled artificially by a dialysis machine (either hemodialysis or peritoneal) or else a prior kidney transplant has failed.

The most common causes of kidney failure are:

• diabetes
• glomerulonephritis, which is an inflammation of the filtering cells of the kidney
• polycystic kidney disease, which is a condition that causes cysts throughout the kidney as well as other abnormalities
• high blood pressure
• congenital problems in children

There are a few conditions that would rule out a transplant entirely. These include:

• cancer that has progressed to a stage where it cannot be cured or arrested
• untreated infections
• severe heart, lung, or liver problems that make transplant surgery or the medication used afterward too risky
• another terminal condition.

Once a person is deemed suitable as a transplant candidate, a donor must be found.

The best situation is for the donor kidney to come from a living donor. A member of one's immediate family is most likely to be willing to donate, and is also most likely to be a good genetic match.

However, many kidneys are now being donated across unrelated lines in a broader sharing effort (called designated donation). The only type of kidney donor that cannot be used is one from a person of a different blood type than the recipient.

If no suitable living donor can be found, the person can be placed on a national waiting list for a kidney from someone who has died. Presently there are 2 commonly used definitions for death in these donors: brain or heart criteria. This waiting list for kidneys is very long. Patients often wait for a kidney for many years, continuing on dialysis all the while, and unfortunately, some die waiting.

How is the procedure performed?

A single kidney is removed from the living, healthy donor in an operating room after the person is put to sleep with anesthesia.

If the donor is dead, both kidneys (for 2 different recipients) are removed at the same time that many other organs (liver, heart, etc.) are being taken for transplantation into others.

The recipient of the kidney transplant is also put to sleep with anesthesia. An incision is made in the lower part of one side of the abdomen. The kidney is transplanted close to the bladder, a location much easier to reach surgically than the usual kidney location, resulting in a quicker and less painful recovery for the recipient.

The blood vessels of the donor kidney must be connected to the corresponding vessels in the recipient's pelvis. The ureter, which is the tubular part of the kidney that carries urine, is connected to the recipient's bladder. There is usually room for the donor kidney to be implanted without having to remove the patient's original kidneys. When all the connections have been made, the incision is closed just like after any other surgery.

What happens right after the procedure?

The hospital stay for a donor is about 2 to 3 days. Recovery after the operation is usually uneventful. The person will have a bladder catheter that is put in place during the surgery. This is usually removed after the first day. The individual is usually up and around within 24 hours, and can resume eating as soon as the anesthesia wears off. The kidney recipient needs to stay in the hospital from 3 to 7 days.

The recipient of the new organ needs to take drugs to suppress the immune system and prevent the body from rejecting the new kidney. These are started either immediately before or during the transplant procedure. The patient is monitored carefully during the first week or two to determine the proper dosages.

The transplanted kidney does not always work immediately after the transplant (a complication more common in kidneys transplanted from donors who have died). The recipient may require dialysis until the new kidney starts to work. The recipients are at risk of infection after surgery.

What happens later at home?

• Walking and deep breathing are encouraged to prevent lung complications and to restore strength.
• Heavy lifting and straining should be avoided for 4 to 6 weeks.
• Driving is permitted once the person's incision is pain free.
• Sexual activity can be resumed when the person is comfortable.
• Other limitations may be imposed by the disease that led to the transplant.

What are the potential complications after the procedure?

There are several potential complications:

• acute kidney failure in the transplanted kidney.
• infection, which happens in roughly 25% of transplant recipients, because of the medications that interfere with their immune system.
• major bleeding, which may require a blood transfusion.
• problems with the blood vessel connections between the donor kidney and the recipient's pelvic vessels.
• a clot in the artery supplying blood to the kidney, or in the vein draining it. If this happens, the kidney may die.
• narrowing of the artery within the kidney. This is known as transplant renal artery stenosis. This can limit blood flow to the kidney. It also makes it difficult to keep blood pressure under control. Most of the time, the narrowed segment can be expanded using a small balloon that is inflated where the narrowing is.
• leaky ureter connections to the bladder or blockage of the ureter (obstruction). This problem is treated by inserting a stent. A stent is a very thin, straw-like tube that provides a kind of scaffolding around which tissues can heal and through which urine can be passed.
• kidney rejection. The body's normal immune response to the new kidney is to reject it. Drugs to suppress the immune system prevent rejection in most cases.
• cancer. Transplant recipients are at somewhat higher risk for cancer as a complication of the drugs that suppress the immune system.

For the most part, kidney transplantation has very good results. Kidney transplant recipients live longer, healthier lives than is possible with dialysis treatments. Although there is a greater short-term risk of death associated with the transplant surgery, this risk is outweighed by the long-term benefits of avoiding long-term dialysis.

Depending on the source and quality of the donor kidney, a successful outcome for kidney transplant can be expected 85% to 95% of the time. A kidney transplant can last an average of 8 to 25 years. Outcomes for living kidney donors are excellent, better than they are with kidneys obtained from dead donors.

The risk of death from donating a kidney is less than 4 in 10,000. There are almost no long-term risks. Living kidney donors do not need to undergo any special medical testing, maintain any special diet, or take any medications as a result of kidney donation. They must be careful to avoid injury to the remaining kidney.