What is a kidney biopsy?
A biopsy is done to remove tissue or cells from the body to exam under
a microscope. The tissue sample is removed with a needle to check for
cancer or other abnormal cells. It also helps check how well the kidney
There are 2 types of kidney biopsies:
Needle biopsy. After an anesthetic is given, the healthcare provider inserts the biopsy
needle into the kidney to get a sample. Ultrasound or computerized tomography
(CT scan) may be used to guide the needle. Most kidney biopsies are done
using this technique.
Open biopsy. After an anesthetic is given, the doctor makes an incision in the skin
and surgically removes a piece of the kidney.
If your healthcare provider wants to sample a specific area of the kidney,
the biopsy may be guided by ultrasound, fluoroscopy, or computed tomography.
Why might I need a kidney biopsy?
Your kidneys are a pair of purplish-brown organs. They sit below the ribs
toward the middle of the back. The kidneys:
- Remove liquid waste from the blood in the form of urine
- Keep a balance of salts and other substances in the blood
- Produce erythropoietin, a hormone that aids the formation of red blood cells
- Regulate blood pressure
When your kidney function is abnormal, a kidney biopsy may be done to:
- Find out the reason for poor kidney function
- Find out if a tumor in the kidney is cancerous
- Check how well a transplanted kidney is working.
There may be other reasons for your doctor to advise a kidney biopsy.
What are the risks of a kidney biopsy?
As with any procedure, complications can occur including:
- Bruising and discomfort at the biopsy site
- On-going bleeding from the biopsy site, in the urine, or inside the body
- Puncture of nearby organs or structures
- Infection near the biopsy site
If the kidney biopsy is done with the aid of X-ray, the amount of radiation
used is small. Therefore, the risk for radiation exposure is low.
If you are pregnant or think you may be, tell your healthcare provider.
Talk to your healthcare provider about the risks to the fetus from being
exposed to an X-ray. Pregnancy is not always contraindication for having
a kidney biopsy. It may be important to maintain the health of the mother.
Special precautions may be taken to protect both the mother and the fetus
during a kidney biopsy.
You may not be able to have kidney biopsy if you have an active kidney
infection, certain bleeding conditions, uncontrolled high blood pressure,
or have only one working kidney.
There may be other risks depending on your specific medical condition.
Be sure to raise any concerns with your healthcare provider before the
How do I get ready for a kidney biopsy?
- Your healthcare provider will tell you about the procedure and can ask
- You will be asked to sign a consent form that gives your permission to
do the kidney biopsy. Read the form carefully and ask questions if something
is not clear.
- Your healthcare provider may do a physical exam to be sure you are in otherwise
good health. You may have blood tests or other diagnostic tests.
- Tell your healthcare provider if you are sensitive to or are allergic to
any medications, latex, tape, and anesthesia.
- Tell your healthcare provider of all medications (prescribed and over-the-counter)
and herbal supplements that you are taking.
- Tell your healthcare provider if you have a history of bleeding disorders
or if you are taking any anticoagulant (blood-thinning) medications, aspirin,
or other medications that affect blood clotting. You may need to stop
these medications before the procedure.
- If you are pregnant or think you might be, tell your healthcare provider
before the procedure.
- You may be asked to fast before the biopsy, generally after midnight or
at least 6 hours before getting anesthetic or sedatives. Your healthcare
team will give you specific instructions.
- You may get a sedative before the procedure to help you relax. Because
the sedative may make you drowsy, you will need to arrange for someone
to drive you home.
- Based on your medical condition, your healthcare team may request other
What happens during a kidney biopsy procedure?
A kidney biopsy may be done on an outpatient basis or in a hospital. It
may be done in a procedure room, in a hospital bed, or in the radiology
department. Procedures may vary depending on your condition and your healthcare
Generally, a kidney needle biopsy follows this process:
- You will remove your clothing and put on a hospital gown.
- An intravenous (IV) line may be started in your arm or hand.
- You will lie on your stomach so that the doctor can easily reach the kidney.
A pillow may be used to hold you in the right position. If you have a
transplanted kidney, you will lie on your back.
- The skin over the biopsy site will be cleaned with an antiseptic solution.
- You will feel a needle stick when the local anesthetic is injected. This
may cause a brief stinging sensation.
- You will need to lie still during the procedure.
- Ultrasound or X-ray may be used to guide the needle into the kidney.
- You will be asked to breathe in and hold your breath while the doctor inserts
the biopsy needle into the kidney. This prevents movement of the diaphragm,
which may interfere with the placement of the biopsy needle.
- You may feel discomfort or pressure when the healthcare provider takes
- There may be more than one puncture if the healthcare provider needs more
than one tissue sample. If so, the same puncture process will be repeated.
- When the needle is withdrawn, firm pressure will be applied to the biopsy
site to stop bleeding.
- A sterile bandage or dressing will be applied.
- The kidney tissue sample will be sent to the lab for testing.
- Talk with your healthcare provider about what you will have during your
What happens after the kidney biopsy?
Your recovery will vary depending on the type of procedure done and your
healthcare provider's practices. You may be taken to the recovery
room and watched closely as the anesthesia wears off. Once your blood
pressure, pulse, and breathing are stable and you are alert, you may be
taken to a hospital room or discharged to your home.
You will be asked to lie on your back for several hours. A nurse will check
your urine for signs of bleeding. You may have blood tests to check for
internal bleeding. You may be discharged later the same day or the next
day. If you had a sedative or anesthetic, plan to have someone drive you home.
The biopsy site may be tender or sore for several days after the biopsy.
Take a pain reliever for soreness as advised by your healthcare team.
You may need to avoid aspirin or certain other pain medications that may
raise the chance of bleeding. Be sure to take only recommended medications.
Tell your healthcare team to report any of the following:
- Blood in your urine after the first 24 hours
- Inability to urinate
- Fever and/or chills
- Redness, swelling, or bleeding or other drainage from the biopsy site
- Increased pain around the biopsy site or elsewhere
- Feeling faint
You may get back to your usual diet unless told otherwise. Your healthcare
team may ask you to rest for a day or two. You will need to avoid strenuous
physical activity for several days. Do not do any type of "bouncing"
activities, such as jogging, aerobics, playing tennis, or horseback riding
for a couple of weeks to prevent bleeding of the biopsy site.
Your healthcare provider may give you other instructions after the procedure,
depending on your situation.
Next steps Before you agree to the test or the procedure make sure you know:
- The name of the test or procedure
- The reason you are having the test or procedure
- The risks and benefits of the test or procedure
- When and where you are to have the test or procedure and who will do it
- When and how will you get the results
- How much will you have to pay for the test or procedure