Rejection and biopsies

Will I reject my kidney?

Rejection is a normal response of your body to a foreign kidney. We will give you medication (immunosuppression) to stop you rejecting your kidney. Despite this medication, about 20% of patients will reject their kidney within the first year, although this may be higher if you have a blood group or antibody incompatible transplant. The risk of rejection decreases with time and is less likely after the first year. Most cases of rejection are mild and can be treated with steroid injections and an increase in the amount or type of immunosuppression you take. Occasionally, we need to treat rejection with drugs that destroy cells of your immune system.

Stopping your prescribed medication, or not taking it properly, is likely to lead to rejection and the possible loss of your transplant. We ask that you take your medication regularly and on time to avoid rejection or other serious consequences. 

Just because you reject your kidney does not necessarily mean that the kidney will fail and most cases of rejection can be stopped with medication. Very rarely (1% of transplants), we cannot stop the kidney rejecting and we have to remove the kidney. In this case, you will return to dialysis and may be considered for another transplant in the future. Most episodes of rejection are picked up by a change in your kidney function on the blood tests and it is unusual for you to have symptoms of rejection. If we suspect that you might be rejecting your kidney, we may ask you to have a transplant kidney biopsy.

Will I need a kidney transplant biopsy?

Most patients do not need a biopsy of their kidney while they are in hospital but if your kidney does not work straight away or if we suspect you have rejection, we may need to do a biopsy of your transplanted kidney. If your kidney takes a long time to start working, you may need a biopsy of the transplanted kidney each week until it starts working.

After you leave hospital, you will be asked to have a surveillance (protocol) biopsy at three months and twelve months after your transplant. The surveillance biopsy is to make sure you do not have rejection that has not been picked up by the blood tests or to see if your kidney is being affected by the medication.

In addition, your transplant doctor may ask you to have a biopsy at any time to make sure there is no rejection or infection in your kidney.

What does a biopsy involve?

The kidney is scanned with an ultrasound machine and local anaesthetic is given at the site of the biopsy to make the skin on the front of your tummy numb. A special needle device is passed into the kidney from the front of your tummy and is used to obtain a small piece of the kidney, about half the size of a matchstick. You will then be asked to lie on your bed for the next four to six hours while the nurses monitor your blood pressure and pulse. You may have had a biopsy of your own kidney. A transplant biopsy is much more straightforward than this.

What are the risks of having a biopsy?

Most kidney biopsies do not have any complications but there is a small risk (about 2 - 5%) of bleeding. Of the patients who bleed, a small proportion require a blood transfusion and a smaller number require a further procedure to stop the bleeding. The risk of damaging your transplant is very small and the benefit of knowing what is going on in the kidney often outweighs the small risk to you of undergoing the biopsy. Your doctor will discuss the risks and benefits of having the biopsy done at the time.