Kidney Transplant

Immunosuppression and Rejection

The immune system is important in protecting the body from infection and cancer. The immune system's T cells circulate in the blood and work to identify foreign tissue; human leukocyte antigens (HLA) are molecules that provide a unique signature on all your cells, informing the T cells which cells in your body are yours.

Your body's immune system is designed to seek and destroy any foreign object that it finds in your body, such as a cold or flu virus — or a transplanted organ. The process of destroying the transplanted organ is called rejection.

Immunosuppressive medications — also called anti-rejection medicine — will be given to stop your immune system from damaging the transplanted organ. Because these drugs decrease the activity of the immune system, they place you at increased risk for certain kinds of infections and cancers. To help prevent these problems, you will receive medications to fight infections, and you will be instructed to change your dose of immunosuppressive medication to avoid dangerous levels. You also will be expected to follow a strict clinic schedule, so that your blood tests and physical exam can be closely monitored

Call your transplant coordinator if:

• You are unable to take your medications because you are vomiting or have diarrhea and are worried that you are not absorbing your medications
• You have forgotten to take your medication or missed any doses due to illness
• The directions on the medication label from the pharmacy are different than what you were told
• You feel you are having an unusual reaction or side effects to a medication
• You would like to take over-the-counter medications, such Tylenol (acetaminophen) for fever
• You are instructed to take any new medications by your local doctor or if any changes are made to your current medications by another doctor

What is Rejection?

Rejection occurs as your body's immune system responds to the presence of the transplanted kidney. However, in transplant recipients, this immune response needs to be suppressed to protect the transplanted kidney.

There are several types of kidney rejection. These types are described by the kind of cells causing the rejection, when the rejection occurs, and by the severity of the rejection.

• Hyperacute rejection: Occurs within minutes of the kidney transplant, when the recipient's antibodies immediately recognize the kidney as foreign and attack it. Hyperacute rejection usually cannot be treated and results in the loss of the kidney. A special test called a crossmatch is completed before kidney transplant to identify antibodies that could cause hyperacute rejection.
• Accelerated acute rejection: Occurs within the first three to seven days after transplantation. This form of rejection is difficult to treat, but there have been recent improvements in treatments for this type of rejection. Patients with high antibody levels (high PRA) are at higher risk for developing accelerated acute rejection.
• Acute cellular rejection: This is the most common form of rejection and can happen at any time. About 15–25% of kidney transplant recipients have at least one mild to moderate episode of acute rejection within the first three months after transplant. Acute rejection can be treated, and having acute rejection does not mean that you will lose your transplanted kidney, but it is extremely important that rejection is diagnosed and treated as soon as possible.
• Chronic rejection: This happens if the rejection process does not completely resolve, or if it continues slowly over time. It is more difficult to treat because of more permanent changes in the kidney tissue, and eventually the kidney will lose all function.

How Do I Know I am Rejecting My Kidney?

When you receive regular kidney-function tests, the patterns of the results will help your doctor observe what is happening to your transplanted kidney. If your blood test results are out of the normal range, your transplant physician or transplant coordinator will discuss the results with you. Some abnormal lab values may be acceptable as you recover from transplant or a related complication and should improve over time.

After you leave the hospital, your blood tests will be monitored less frequently. If rejection occurs, you may experience some mild symptoms, although some patients may continue to feel fine for a while. The most common early symptoms include:

• Fever greater than 100°
• Increased kidney function tests
• Decreased urine output
• Tenderness over the graft
• Swelling of hands, eyelids, or lower extremities
• Weight gain of 2–4 lbs (1-2 kgs) in 24 hours

Additionally, your doctor may want you to have a kidney biopsy to confirm that your symptoms are caused by rejection.