This leaflet answers common questions about Native Kidney Biopsies. If you would like further information, or have any worries, please do not hesitate to ask your nurse or doctor.

In all cases, a doctor will explain the Native Kidney Biopsy to you and answer any questions you may have. In most cases it will be possible for a friend or relative to accompany you for all or part of the procedure. Please ask your nurse or doctor.

What is a native kidney biopsy?

A kidney or renal biopsy means taking a small sample (about half a matchstick in size) from one of your kidneys using a special needle. The sample can then be tested under a microscope to find out the cause of your kidney disease.

Why do I need a kidney biopsy?

Your kidney doctor will use this to find out what is wrong your kidney and which treatment, if any, you would benefit from. It is felt that the information from the biopsy makes the small risk of a biopsy worthwhile and it is important you agree about this.

Where is it done?

The biopsy is carried out in a procedure room on PITU ward on 2nd floor at the Royal Free Hospital.

Before your procedure

You can eat and drink normally before and after the biopsy is done, but you should avoid heavy meals for two hours beforehand. You may be asked to stop some medications in the days before your procedure; your nurse or doctor will discuss this with you.

How is a native kidney biopsy done?

It takes about 20 minutes and is performed under local anaesthetic so you will remain awake. You will be asked to lie down. The doctor will use an ultrasound machine to locate the kidney. The skin over the kidney will be cleaned with antiseptic and local anaesthetic will be injected into the skin. It may sting at first and once the skin is numb more local anaesthetic is injected around the kidney.

The biopsy needle will then be passed through the numb area and the kidney sample taken. You should not feel pain, but you may feel a little pressure and hear a clicking sound when the biopsy sample is taken. The doctor may take two or three biopsy samples. Pressure will then be applied to the area to prevent bleeding.

After your procedure

You will then rest in bed for at least six hours. Your pulse and blood pressure will be monitored and when you pass urine it will be tested for bleeding. During this time, you can eat and drink normally. You must let us know if you feel severe pain in the kidney or on trying to pass urine. Mild pain in the back is common and is due to slight bruising for which we can give you a painkiller.

If you feel well after the biopsy and have no pain or bleeding, you may be able to go home later that day or the following day. You should avoid exercise, excessive bending or lifting for 72 hours and if you develop severe pain around the kidney or any blood in the urine you should contact us straight away.

Risks and side-effects

The risk of a serious complication is small. This risk will be explained to you by the doctor doing the procedure. These include:

  • The biopsy needle can damage the kidney or other parts of the body nearby.
  • Bleeding is the most serious complication. You will have a blood test before the biopsy to make sure your blood clots normally. It is important that you tell your doctor if you have any problem with easy bleeding or bruising or if you are taking tablets that can affect bleeding such as aspirin, clopidogrel, apixiban, rivaroxaban (and certain other drugs ending in -aban) or warfarin. Normally these will need to be stopped several days before the procedure.
  • In about 1 in 10 biopsies there is visible bleeding in the urine that settles by itself.
  • In about 1 in 100 biopsies there is more bleeding that requires a blood transfusion.
  • In less than 1 in 500 biopsies the bleeding may continue and require an urgent x-ray procedure or even an operation to stop the bleeding. In less than 1 in 3000 biopsies the kidney may have to be removed to stop the bleeding. Although deaths have occurred following complications of biopsies this is extremely rare. The Royal Free has an excellent safety record for biopsies and we successfully perform many hundreds every year.

Native kidney biopsy alternatives

A biopsy is usually the last test to be done to work out what is wrong with your kidneys because the other tests have not provided the answer. Without a biopsy your doctor may not be able to advise the best treatment for you. Your doctor should be able to tell you what changes in treatment could be made for your kidneys if you decide not to have a biopsy taken first.

If you agree to have the biopsy you will be asked to sign the Royal Free’s consent form which will state that you have received information about the procedure and have discussed it with your doctor.

Do you have any further questions?

Questions about your condition should be addressed to your consultant (contact via their secretary).

Other useful contacts

If you have pain, blood in the urine or concerns after a recent biopsy procedure please go to your nearest emergency department (A&E), or if the symptoms are severe call an ambulance. Take a copy of your hospital discharge letter with you.