Patient education: Kidney biopsy (The Basics)

What is a kidney biopsy? — This is a procedure to check the kidney or look at an abnormal area for cancer or other problems. It is also called a "renal biopsy."

People usually have 2 kidneys, 1 on each side of the mid-back (figure 1). The kidneys filter blood and remove waste and excess salt and water.

You might get a kidney biopsy if other tests, like blood and urine tests, do not give enough information about your kidneys. A biopsy can help your doctor learn more about:

●What is causing your kidney problems

●How serious your kidney problems are

●Possible treatments

There are different ways to do a kidney biopsy.

How do I prepare for a kidney biopsy? — The doctor or nurse will tell you if you need to do anything special to prepare. Before your procedure, your doctor will do an exam. They might send you to get tests, such as:

●Blood tests

●Imaging tests like a CT scan or ultrasound – These create pictures of the inside of the body.

Your doctor will also ask you about your "health history." This involves asking you questions about any health problems you have or had in the past, past surgeries, and any medicines you take. Tell them about:

●Any medicines you are taking – This includes any prescription or "over-the-counter" medicines you use, plus any herbal supplements you take. It helps to write down and bring a list of any medicines you take, or bring a bag with all of your medicines with you.

●Any allergies you have

●Any bleeding problems you have – Certain medicines, including some herbs and supplements, can increase the risk of bleeding. Some health conditions also increase this risk.

You will also get information about:

●If you need to stop taking any medicines for a time before the biopsy. Follow your doctor's instructions carefully to know which medicines are safe to take and which to avoid. Examples of ones you might need to stop include:

•Aspirin or aspirin-containing medicines

•Other nonsteroidal antiinflammatory drugs ("NSAIDs") such as ibuprofen (sample brand names: Motrin, Advil) or naproxen (sample brand name: Aleve). Many non-prescription medicines contain NSAIDs, so check the labels or ask your pharmacist for help.

•Medicines used to prevent blood clots, such as warfarin (brand name: Jantoven) or rivaroxaban (brand name: Xarelto)

•Certain medicines for heart conditions, such as dipyridamole (brand name: Persantine) or clopidogrel (brand name: Plavix)

•Certain natural products, such as fish oil or ginkgo biloba

●Eating and drinking before your procedure – In some cases, you might need to "fast" before the biopsy. This means not eating or drinking anything for a period of time. In other cases, you might be allowed to have liquids until a short time before the procedure. Whether you need to fast, and for how long, depends on the procedure you are having.

●What help you will need when you go home – For example, you might need to have someone else bring you home or stay with you for some time while you recover.

Ask the doctor or nurse if you have questions or if there is anything you do not understand.

What happens during a kidney biopsy? — This depends on the type of biopsy you have. The choice is based on:

●Your health and any medical problems you have

●The size and location of the abnormal area

●What the kidney looks like with ultrasound or other imaging tests

When it is time for the procedure:

●You will get an "IV," which is a thin tube that goes into a vein. This can be used to give you fluids and medicines.

●The doctors and nurses will monitor your breathing, blood pressure, and heart rate during the procedure.

●For all biopsies, you will get an injection (shot) first to numb the area. You might also get other medicines to help you relax and feel sleepy.

●The 3 main types of kidney biopsies are:

•Percutaneous biopsy – "Percutaneous" means through the skin. This might also be called a "fine-needle biopsy." The doctor cleans and numbs the skin on the back over the kidney. They might use an ultrasound to guide them as they insert a needle to do the biopsy. They use the needle to remove a small sample of tissue from the kidney. Then, they remove the needle and hold pressure to stop any bleeding.

•Transjugular biopsy – This is most often done in people who are at a high risk of bleeding. The doctor places a thin tube called a "catheter" into a vein in the neck. Then, they use fluoroscopy (a type of moving X-ray) to push the catheter to a vein in the kidney. They insert a special needle through the catheter to take a small sample of tissue from the kidney. Then, they remove the needle and catheter and hold pressure to stop any bleeding.

•Surgical biopsy – This is done in an operating room under general anesthesia. General anesthesia makes you unconscious so you can't feel, see, or hear anything during the procedure. The doctor makes a small cut (incision) on the back over the kidney and takes a small sample of tissue from the kidney. Then, they close the incision.

●If you have a percutaneous or transjugular biopsy, you might feel pressure when the doctor takes the biopsy, but it should not hurt.

●After they are finished, the doctor will cover the area with clean bandages.

●Most kidney biopsies take about 60 minutes.

What happens after a kidney biopsy? — After your procedure, you will be taken to a recovery room. The staff will watch you closely as you recover. You might need to lie in bed for 4 to 6 hours. If you urinate, the staff might collect a urine sample to send to the lab.

If there are no problems, you might be able to go home about 12 to 24 hours after the biopsy.

As you recover:

●If you had general anesthesia:

•You might feel groggy or confused for a short time. You might also feel nauseous or vomit. The doctor or nurse can give you medicine to help with this.

•You might have a sore throat if you had a breathing tube. This usually gets better quickly.

●The staff will help you get out of bed and start moving around when you are ready.

●You will get medicine if needed to help with pain. You might need other medicines, too.

●When you are ready to eat, you will start with clear liquids. Then, you can start eating as you are able. You might feel better if you start with bland foods.

What are the risks of a kidney biopsy? — Your doctor will talk to you about all of the possible risks, and answer your questions. Possible risks include:

●Bleeding

●Infection

●Injury to blood vessels or other organs

●High blood pressure

●Ongoing pain

●A collapsed lung (called a "pneumothorax")

What else should I know? — Before you go home from the hospital, make sure that you know what problems to look out for and when you should call the doctor. Make sure that you understand your doctor's or nurse's instructions. Ask questions about anything you do not understand.

More on this topic

Patient education: Kidney biopsy – Discharge instructions (The Basics)
Patient education: Chronic kidney disease (The Basics)
Patient education: Granulomatosis with polyangiitis (The Basics)

Patient education: Kidney (renal) biopsy (Beyond the Basics)
Patient education: Chronic kidney disease (Beyond the Basics)