Although rates of serious complications have fallen sharply in the last few decades, kidney transplants – like any other type of surgery – are not risk-free.
The risks of a kidney transplant include:
- risks related to the procedure itself
- risks related to the use of immunosuppressant medicines (which reduce the activity of your immune system)
- risks related to something going wrong with the transplanted kidney
Most complications happen in the first few months after a transplant but can develop after many years.
Short-term complications
Infection
Minor infections, such as urinary tract infections (UTIs), colds, and flu, are common after kidney transplants.
You can also get more serious infections, such as pneumonia and cytomegalovirus (CMV), which may require hospital treatment.
Blood clots
Blood clots can develop in the arteries that have been connected to the donated kidney. This is estimated to happen in around 1 in 50 kidney transplants.
It may be possible to dissolve the blood clots using medicine, but it's often necessary to remove the donated kidney if the blood supply is blocked.
There is also a risk of developing blood clots in the legs. This is called deep vein thrombosis (DVT).
Narrowing of an artery
Narrowing of the artery connected to the donated kidney, known as arterial stenosis, can sometimes happen after a kidney transplant. Sometimes, it can develop months, or even years, after the transplant.
Arterial stenosis can cause a rise in blood pressure. The artery often needs to be stretched to widen it, and a small metal tube called a stent may be placed inside the affected artery to stop it from narrowing again.
Blocked ureter
The ureter (the tube that carries pee from the kidney to the bladder) can become blocked after a kidney transplant. It can be blocked soon after the transplant – by blood clots, for example. It can also be blocked months or years later, usually due to scar tissue.
It may be possible to unblock the ureter by draining it with a small tube called a catheter. Sometimes surgery may be required to unblock the ureter.
Urine leakage
Occasionally, urine may leak from where the ureter joins the bladder after surgery. This usually happens during the first month after the procedure. The fluid may build up above the abdomen or leak through the surgical incision.
If this happens to you, then consult your physician immediately.
Acute rejection
Acute rejection defines the immune system and suddenly begins to attack the donated kidney because it recognizes it as foreign tissue.
Despite the use of immunosuppressants, acute rejection is a common complication in the first year after a transplant, affecting up to 1 in 3 people.
In many cases, acute rejection does not cause noticeable symptoms and it gets only detected by a blood test.
If it does happen, it can often be successfully treated with a short course of more powerful immunosuppressants.
Long-term complications
Immunosuppressant side effects
Immunosuppressants prevent your body's immune system from attacking the new kidney and try to damage it or destroy the transplanted kidney
A combination of 2 or 3 different immunosuppressants is usually taken long-term.
These can cause a wide range of side effects, including:
- an increased risk of infections
- an increased risk of diabetes
- high blood pressure
- weight gain
- abdominal pain
- diarrhea
- Excessive growth of hair or hair loss
- swollen gums
- bruising or bleeding more easily
- osteoporosis
- acne
- mood swings
- an increased risk of certain types of cancer, particularly skin cancer
The doctor in charge of your care will be trying to find the right dose that is high enough to "dampen" the immune system to stop rejection but low enough that you experience very few or no side effects.
