What is a renal biopsy?
This medical procedure involves taking a small sample tissue (biopsy) from the kidney so that it can be examined under the microscope. It is usually done on the left kidney. From renal transplant recipients it is done from the transplanted kidney.
Why am I having a renal biopsy?
This gives information on the cause of your type of kidney disease, which will help doctors understand what caused it, how severe it is, what treatment is necessary and whether it might run in the family.
Renal transplant patients undergo a biopsy usually at 3 months and 1 year after transplantation. This helps us to find out if there is ongoing damage to the kidney (sub-clinical rejection) and will guide us to alter the immunosuppressive medications.
Renal transplant patients may need to undergo biopsy at other times as determined by the doctors if there is a abnormal blood result.
Risks of a renal biopsy
There is a 5 per cent risk of doctors taking an unsatisfactory tissue sample, meaning the procedure may need to be repeated.
There is a 5 per cent risk of significant bleeding from the kidney. If the bleeding occurs around the kidney, you may feel back pain. If the bleeding occurs inside the kidney, you may see blood in the urine.
If there is low blood pressure associated with the bleeding, you may need intravenous fluids. In less than 1 in 100 cases, a blood transfusion or special procedure to stop the bleeding may be necessary.
- Your doctor may ask you to stop clopidogrel (PLAVIX©) and/or aspirin for the week before the procedure.
- You should have blood tests of your blood clotting system. If you have not had a blood test within 6 weeks to check the clotting system you may need to have one on the day of the procedure.
- If you are anxious before the procedure, you may ask for a mild sedative.
What happens during a renal biopsy?
You will be asked to change into a hospital gown and will be taken to the procedure room on a hospital trolley. You will have an intravenous cannula inserted.
You will be asked to lie face down on the trolley, placing 2 or 3 pillows under your belly. This position helps the doctor get access to the kidneys.
After drawing a mark on your skin and rubbing a special gel on your back, the doctor uses an ultrasound to find your kidneys, and measure how far they are under your skin.
The doctor will then rub your back with antiseptic, cover your body with sterile sheets, and numb your skin with a local anaesthetic. Additional anaesthetic will be used around the skin above your kidney.
The doctor will insert a special biopsy needle into your back, and down into your kidney. Usually 2 to 3 samples of kidney tissue are taken, which are only 5 to 10mm long, and 1mm wide. Sometimes the procedure might have to be repeated 4 or 5 times to get an adequate sample.
The samples are checked by a laboratory technician and if satisfactory, you are allowed roll over on to your back and are wheeled back to the ward.
You will be observed closely in bed by nursing staff for 3 to 4 hours, then allowed to stand up. All urine samples will be tested for blood. If there are no complications, you may leave hospital.
You will be required to stay for up to 4 hours for a transplant kidney biopsy and up to 6 hours after biopsy to your native kidneys.
You may restart the aspirin and clopidogrel the following day, if there are no complications.
If you notice undue pain or blood in the urine please present immediately to the emergency department.
You have the right to refuse an examination and may do so if you wish. You may be asked to complete a consent form.
When will I get the results?
The samples go to 3 separate laboratories, which produce their answers in 1 to 4 weeks.
You should make an appointment to discuss the results with your doctor.
After the renal biopsy
It is preferable to get someone to drive you home or take public transport.
You should avoid lifting heavy weights and doing heavy manual work for 1 week after the biopsy
Mild aching in the biopsy area is usual, and should be treated by paracetamol if necessary.
You will have an appointment with your doctor within 2 to 3 weeks to discuss the results of the biopsy.
If there is any significant back pain, dizziness or low blood pressure, or blood in the urine, please ring your doctor, lie down and drink plenty of fluids. Keep your urine samples in jars, so that the rate of improvement can be assessed.
Costs of a renal biopsy
For an Australian patient in a public hospital in Western Australia:
- public patient – no cost to you unless advised otherwise
- private patient – costs can be claimed through Medicare and your health insurance provider.
For a patient in a private hospital or private imaging site in Western Australia – ask your doctor or the staff where you are having your test done.
Where to get help
- See your doctor
- Ring healthdirect on 1800 022 222
Renal Unit, Royal Perth Hospital
This publication is provided for education and information purposes only. It is not a substitute for professional medical care. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your healthcare professional. Readers should note that over time currency and completeness of the information may change. All users should seek advice from a qualified healthcare professional for a diagnosis and answers to their medical questions.