Having a kidney biopsy: your questions answered

This leaflet aims to answer any questions you may have about your biopsy. If after reading it you are still unsure about anything, please do not hesitate to ask the doctor or nurse on the ward.

What is a biopsy?

A biopsy is the removal of a small piece of tissue from an organ of the body, for example the kidney, using a specially designed needle. A biopsy is only taken from one of your kidneys, since this sample will show what is happening in both your kidneys.

Why do I need a biopsy?

If your kidneys are not working properly, we need to find out why this has happened. Sometimes the only way to find out is to take a small specimen of tissue from one kidney and examine it under a microscope in a laboratory. This will help us make the correct diagnosis.

Where will I have my biopsy?

Usually we do biopsies in our clean procedure room next to Marlowe Ward at Kent and Canterbury Hospital. Occasionally your biopsy may need to be done in the X-ray Department.

Will I have to stay in hospital?

You will be admitted to Marlowe Ward day case area on the day of your biopsy. Most people having a biopsy are able to return home the same day, usually eight hours after their procedure.

For reasons of safety, some people will need to stay in hospital for one night after their biopsy. This includes those with low kidney function (eGFR <20 ml / min) and in certain other situations. You will be told by your usual doctor in advance if you need to stay overnight.

What are the risks of a kidney biopsy?

Any medical or surgical procedure carries risks. The main risk associated with a kidney biopsy is bleeding in to the urine or around the kidney. Around one in 10 people will see blood in their urine after their biopsy, but this usually clears quickly.

Occasionally, and only in the event of very heavy bleeding in to the urine, we may need to place a urinary catheter (a small tube in to the bladder through the urethra) to allow bladder irrigation and prevent large blood clots from forming in the urine.

Our local data (from over 1000 biopsies carried out by the Trust over a five year period) tells us that the risks of other serious complications are:

• heavy bleeding needing blood transfusion happens in approximately one in 50 cases

• intervention (usually undertaken by an interventional radiologist) to stop ongoing bleeding happens to approximately one in 75 cases.

Data published in the medical literature tells us that death is a very rare but recognized complication of a kidney biopsy, but we did not find any deaths attributed to the procedure in our local data.

Do I need to bring anything with me?

Please bring a list of your medications and any medications you may need on the day of your biopsy. You may wish to bring something to read. If you are staying overnight, please make sure that you bring the necessary items.

What if I am taking anticoagulants (blood thinners)?

If you are taking aspirin, clopidogrel, dipyridamole, warfarin, apixaban, rivaroxaban, or dabigatran you will need to stop taking these before having your biopsy. Please discuss the timing of this with your kidney doctors and tell your usual anticoagulant clinic if you stop taking your warfarin.

What happens before I have my biopsy?

• Blood samples may be taken in the clinic, or you may be asked to have them taken at your GP surgery. These are to make sure that it is safe to do the biopsy.

• Only eat a light breakfast on the morning of your biopsy.

• If you have diabetes, please tell the nurse looking after you on the ward. When you have been admitted to hospital your blood pressure will be checked, an intravenous cannula will be inserted in to one of your veins, and further blood samples will usually be taken.

• One of the kidney doctors will make sure that you understand what the biopsy involves and explain the risks to you. You will be asked to sign a consent form agreeing to have the biopsy. Remember you can withdraw your consent for treatment at any time.

• You will be asked to put on a theatre gown and to go to the toilet to empty your bladder before your procedure.

What happens during my biopsy?

The biopsy is performed in the clean procedures room next to Marlowe Ward. You will remain awake throughout your procedure.

• You will be asked to lie on your front and a couple of pillows may be placed under your stomach. This allows the doctor easy access to your kidneys, which are in the back of your abdomen (stomach) on either side.

• The position of your kidneys is checked using an ultrasound scan and then an antiseptic solution is used to clean your skin. Sterile towels are then draped around the cleansed area and an injection of local anaesthetic is given to numb your skin and the area around your kidney.

• You will be asked to hold your breath and keep still while the biopsy needle is introduced through the skin in to your kidney. Usually two small samples will be taken. This part of the procedure is very quick, but it may need to be repeated to get a sufficient sample for analysis.

Will the biopsy hurt?

You may feel a slight stinging from the injection of local anaesthetic and some pressure from the biopsy needle, but otherwise the procedure should not be painful. If you do feel anything more than a little discomfort, please tell your doctor straightaway.

What happens immediately after my biopsy?

A small dressing will be used to cover the skin biopsy site. You will be asked to lie as flat as possible on your back in bed for four hours, and then sat up for the next two hours before moving around for two hours before your discharge from hospital.

During this time your blood pressure, pulse, and biopsy site will be checked regularly. If you become aware of bleeding or pain you should tell the nurse looking after you. You will be asked for a sample of urine so they can look for any signs of blood. It is important that you do this, as this will reduce risk of and/or alert the doctors and nurses to any bleeding complications.

What happens in the days following my biopsy?

Once home you should rest. It is quite normal to have some discomfort around your biopsy site during the first week. You may need to take some over-the-counter pain relief (such as paracetamol) for this.

We advise you not to do anything too physically strenuous (for example contact sports such as horse riding, football, rugby, and boxing) or carry out any heavy lifting for at least two weeks after your procedure, as this could dislodge the blood clot around the biopsy site and lead to bleeding.

You should be able to return to normal light activities four days after your biopsy.

If you have stopped taking your anticoagulants you should discuss with your kidney doctor when to restart them.

If you have any dizziness, visible blood in your urine, or severe back pain after returning home, please contact Marlowe Day Case Area on 01227 783100.

When do I get my results?

• In urgent cases your biopsy result is made available to the doctor looking after you on the ward within 48 hours.

• The full report in non-urgent cases may take up to four weeks. In non-urgent cases you will usually be given an outpatient appointment at the hospital within four weeks of your biopsy.

When can I drive again?

You should arrange for somebody to collect you from the hospital after your procedure. We strongly advise you not to drive yourself home after your procedure, or to travel home by public transport. If you do not have a friend or relative who can drive you home, please tell the nurse looking after you and we will make necessary arrangements with Patient Transport Services.

You should not start driving again until you feel comfortable. In particular, you need to be able to perform an emergency stop safely.