Kidney Biopsy

A kidney biopsy is a medical test, where a small sample of tissue is removed from your kidney with a needle. The sample is then sent to the pathology department where it is examined under a microscope.

A kidney biopsy helps to assess and diagnose the problem, if any, in your kidney. Kidney biopsies are usually done for one of three reasons.

1. To find out why a kidney is not functioning properly.
2. To get a sample of a mass on a kidney.
3. To assess a kidney before a kidney transplant.

The importance of a kidney biopsy is that it allows for the kidney cells to be assessed by a pathologist to help make a correct diagnosis and plan any necessary treatment.

There is no other procedure that will give your doctor the same information as a kidney biopsy.

A kidney biopsy is usually a safe procedure. Potential complications are uncommon and include:

• Some people experience pain, which is usually not severe and can be controlled with simple painkillers.
• Bleeding or bruising around the puncture site which should settle down by itself. 
• There is a small risk of minor internal bleeding after the biopsy. The risk is around 1 in 20 and will usually settle down by itself. The nurse will monitor your blood pressure and pulse during and after the procedure and you will stay in hospital for up to five hours after the procedure so that we can monitor you.
• Some people pass blood in their urine after a biopsy. This will usually settle on its own within a few days. If you continue to pass blood for more than 1 week or if you pass a lot of blood, then contact the Imaging department to ask for assessment and advice. If you become unwell out of working hours, then attend A&E. The number for the Imaging department can be found on your appointment letter.
• Occasionally people will have a significant bleed, in which case it may be necessary to do a further procedure to try to stop the bleeding. This will occur in approximately 1 in 50 people.
• There is a very small risk of death. This risk is less than 1 in 1000.

You will need to have a blood test a few days before the procedure to check that you are not at increased risk of bleeding and that it will be safe to take the biopsy. This may be arranged to take place at your GP surgery. 

You can continue taking your normal medication. If you are on any medication that thins the blood we ask you to call the Imaging department using the number on your appointment letter. We may need to adjust your medication before undergoing this procedure. These may need to be stopped to keep the risk of bleeding to a minimum. This medication includes but is not limited to; aspirin, clopidogrel, warfarin, rivaroxaban, dabigatran and apixaban. 

Please arrange for someone to collect you from the hospital and take you home by car, as we advise you not to use public transport. You are not permitted to drive for 24 hours post-procedure and we would like someone to stay with you at home in the first 24 hours. Please inform the department if this is not possible, as we will need to identify alternative arrangements.

• You should eat nothing for six hours before your appointment. You may drink water until the time of your appointment.
• You will arrive at Gate 19 and be accompanied into our day case area.
• You may take your normal medication unless instructed otherwise. It would be useful to bring a list of your usual medications.
• Please inform us if you are allergic to anything. n You will be asked to change into a hospital gown and a small plastic tube (cannula) may be put into your arm.
• A radiologist (x-ray doctor) will discuss the procedure with you. You will be given an opportunity to ask questions. If you want to go ahead with the procedure you will be asked to sign a consent form.
• Once all the checks have been performed and consent signed, you will be taken to the procedure room on the trolley. There will be a nurse and a radiologist with you throughout the procedure.
• The radiologist will use an ultrasound machine to look at your kidney to find the correct area to take the biopsy from.
• Your skin will be cleaned with an antiseptic solution and covered with sterile drapes.
• The radiologist will then inject a local anaesthetic into the area selected for biopsy, which will briefly sting and then go numb. Most people will feel a pushing sensation, but the biopsy is not usually painful. A special needle is used to remove a small piece of kidney tissue. Occasionally it is necessary to take more than one sample.
• Once the radiologist has taken the sample, the needle will be removed, and the radiologist will apply a dressing.

• You will be taken back to the day case area so that the nursing staff may monitor you closely.
• If you are in pain tell the nursing staff so you can be given appropriate painkillers.
• You will be required to stay flat for one hour and then sit up for a further two hours. Then walk around for half an hour.
• You will be able to eat and drink as normal.
• If everything is satisfactory, you will be free to go home. Please arrange for someone to collect you on discharge rather than drive yourself. n Have someone stay with you overnight.
• You should rest for the remainder of that day and the following day, avoiding any strenuous activities for 36 hours.
• Keep a regular check on the biopsy site. The dressing can be removed after 24 hours.
• If you have any discomfort, take your usual pain relief as prescribed. But, if the pain is severe please contact the Imaging department using the number on your appointment letter.
• Some people pass blood in their urine after a biopsy. This will usually settle on its own within a few days. If you continue to pass blood for more than 1 week or if you pass a lot of blood, then contact the Imaging department to ask for assessment and advice. If you become unwell out of working hours, then attend A&E.

The results of the biopsy will be sent to the consultant who referred you, who in turn will either contact you or write to your GP with the results. 

If you experience any symptoms you are concerned about, please contact the Imaging department directly on the number on your appointment letter or contact your GP or the emergency department. 

Finally, we hope this information is helpful. If you have any questions either before or after the procedure the staff in the Imaging department will be happy to answer them.

North Bristol NHS Trust (2022) “Ultrasound Guided Liver Biopsy” 

North Bristol NHS Trust (2022) “Kidney Biopsy Information for Patients” 

Halimi, J., Gatault, P., Louguet, H., Barbet, C., Bisson, A., Sautenet, B., Herbert, J., Buchler, M., Grammatico-Guillon, L. & Fauchier, L. Clinical Journal of the American Society of Nephrology (2020) “Major Bleeding and Risk of Death after Percutaneous Native Kidney Biopsies”