Kidneys help our bodies filter blood to eliminate waste products and extra fluid, which helps to regulate our blood pressure. When something in our kidneys is not working correctly, it can cause damage and lead to disease. There are several tests you can get to determine this damage, including blood tests, urine tests, imaging techniques, and kidney biopsy.

Kidney biopsies are a way for doctors to test tissue from your kidneys to help diagnose problems. Your doctor might order one if you have blood or protein in your pee, if you have abnormal test results, or if they suspect you have kidney disease. A kidney biopsy is performed by a nephrologist (a doctor who specializes in kidney conditions) or an interventional radiologist (a doctor who performs imaging-based procedures).

Kidney biopsies can help diagnose different types of kidney disease, including rare kidney diseases like complement 3 glomerulopathy (C3G) or immune complex-mediated membranoproliferative glomerulonephritis (IC-MPGN). Kidney biopsies are also used to:

• Monitor chronic kidney disease
• Determine the extent of damage to the kidneys
• See how well kidneys respond to treatment
• Check if transplanted kidneys are working
• Take a sample of a tumor to check for cancer

Getting a new procedure performed might be intimidating, but testing is an important part of helping doctors figure out what might be going on with your kidneys. In this article, we’ll talk about what to expect from a kidney biopsy so you can go in feeling prepared.

How To Prepare for a Kidney Biopsy

Before you go in for a biopsy, your doctor will likely give you specific instructions about what to do or not do before the procedure. They will advise you to stop taking certain medications that can increase the risk of bleeding. These include blood thinners as well as pain medications like aspirin, ibuprofen, and naproxen. They may also want you to stop taking certain herbal supplements.

If you have any questions about which medications you should stop before your biopsy, consult your doctor. They may also give you a time frame for when to stop eating or drinking prior to the procedure.

Your doctor may do a few more tests before the biopsy — such as getting blood work, taking urine samples, or performing a physical exam — to determine whether you’re healthy enough to undergo the procedure, as well as to check for infections. If everything looks good, they will proceed with the biopsy.

What To Expect During a Kidney Biopsy

On the day of your biopsy, you’ll meet with your healthcare provider. Biopsies are typically performed in a hospital. You may be given general anesthesia, in which case you’ll be asleep for the procedure. Otherwise, your doctor might put you under light or moderate sedation, meaning you’ll be awake but relaxed.

Most of the time, you will be lying on your stomach for the procedure. If the biopsy is being done on a transplanted kidney, then you will be on your back.

There are two different ways kidney biopsies are performed using all aseptic precautions (strict rules about cleanliness). Both take about an hour.

Percutaneous Biopsy

For a percutaneous (through the skin) biopsy, the doctor will insert a needle into your skin to take a tissue sample. To find the kidney, they will use imaging devices, such as an ultrasound. They will numb your skin before inserting the needle.

If you are awake during the procedure, they might ask you to hold your breath while they take the sample, which will prevent you from moving too much. Once they take the needle out, you’ll get a bandage to cover the spot where the needle went in.

Open Biopsy

In an open biopsy, the doctor will make a small incision (cut) in your skin to open up the layers of tissue to get to the kidney. From there, they will remove a small sample of your kidney. Then they will stitch up the incision site.

What Happens After the Biopsy

After the procedure is finished, you’ll be moved into a recovery room to be monitored by the healthcare team. They will run some more tests to make sure your vital signs look good and to make sure you can drink and urinate before you go home. Depending on how quickly you recover, you could be in the hospital for a few hours after the procedure, or they might have you stay overnight so they can keep a closer eye on you.

You will not be able to drive home after the procedure, because you’ll be on medications that make driving dangerous. It is a good idea to plan how you will get home after the procedure.

Biopsy Recovery

Once you’re home, you’ll typically be required to lie low for a couple of days to help with recovery. Lying flat on your back is the best position to help your kidneys recover. If you had an open biopsy, recovery will take a bit longer and usually will be more painful than the percutaneous procedure. After a percutaneous biopsy, some soreness is normal.

When you leave the hospital, your medical team will give you specific instructions on how long you’ll need to rest, what medications can help with the pain, and how long you’ll have to wait before you can return to more strenuous activities. They will also instruct you on how to monitor your symptoms to make sure you are healing well.

You’ll want to keep a bandage over the biopsy site for a couple of days to let it heal. Your medical team will give you specific instructions about when you can get the incision area wet and shower. To limit the risk of infection, you won’t want to soak the biopsy site until it scars over. (This means avoiding baths, swimming, and hot tubs.)

Ask your doctor what you can eat and drink. They will probably recommend that you drink a lot of water. You are not restricted in what you can eat, so feel free to resume your normal diet.

Biopsy Risks

As with most medical procedures, there are associated risks. Kidney biopsies are a relatively simple procedure, but there are still risks that you should be aware of. The biggest risk during the procedure is excess bleeding if a blood vessel gets cut. If this happens, the medical team will take steps to stop the bleeding immediately.

After the procedure, there is a small risk of infection. Other risks include urinary retention (difficulty peeing) and a urinary tract infection.

If any of these problems arise, make sure to tell your doctor right away.

Results

Ask your doctor how soon you can expect your biopsy results. Many people can get results within three to five days. Kidney biopsies can help to diagnose rare kidney diseases and help the medical team determine what treatments will be most helpful. There is a chance that the results from the biopsy will be inconclusive, which means that there aren’t any results or doctors are unable to make a diagnosis. If this is the case, your doctor will help determine the next best steps.

Talk With Others Who Understand

MyKidneyDiseaseTeam is the site for people with rare kidney disease and their loved ones. People come together to ask questions, give advice, and share their stories with others who understand life with kidney disease.

Are you living with kidney disease? Have you had a kidney biopsy? Share your experience in the comments below, or post on your Activities page.