biopsy is usually done using a long thin needle put through
the back (flank) into the kidney. This is called a percutaneous kidney biopsy.
A tissue sample is taken and sent to a lab. It is looked at under a microscope.
The sample can help your doctor see how healthy your kidney is and look for any
kidneys are found on either side of the spine, in the
lower back. They help the body balance water, salts, and minerals in the blood.
The kidneys also filter waste products from the blood and make urine.
A kidney biopsy may be done to check for kidney problems. It may also be
done after other tests for kidney disease, such as blood and urine tests,
ultrasound, or a
computed tomography (CT) scan, show a kidney problem.
Why It Is Done
A kidney biopsy is done to:
- Find kidney disease when there is blood or protein in the urine
or when the kidneys are not working well.
- Check kidney problems seen on an ultrasound or a CT scan.
- Watch kidney disease and see if treatment is working.
- Find out why a transplanted kidney isn’t working well.
- Find out more information about a tumor found in the kidney.
How To Prepare
Tell your doctor if you:
- Are taking any medicines. If you are taking aspirin, nonsteroidal
anti-inflammatory medicines (NSAIDs, such as ibuprofen or naproxen), or blood
thinners (such as Coumadin, heparin, or Plavix), your doctor may tell you to
stop taking these medicines for several days before the biopsy.
- Are allergic to any medicines, such as those used to numb the
- Have had bleeding problems.
- Are or might be pregnant.
Follow the instructions exactly
about when to stop eating and drinking, or your test may be canceled. If
your doctor has instructed you to take your medicines on the day of the test,
please do so using only a sip of water.
Arrange to have someone take you home after the biopsy
because you may be given a medicine (sedative) to
help you relax.
You will have blood tests done before the kidney
biopsy to see whether you have any bleeding problems or blood clotting
disorders. You may also have an ultrasound test or CT scan of the kidney to
show the best place in your kidney to put the biopsy needle.
You will be asked to sign a consent form that says you understand the risks of the test and agree to have it done.
Talk to your doctor about any concerns you have regarding the need for the test, its
risks, how it will be done, or what the results will mean. To help you
understand the importance of this test, fill out the
medical test information form (What is a PDF document?).
How It Is Done
A kidney biopsy is done by a
nephrologist, or a
radiologist in a clinic or a hospital. A kidney biopsy
is often done by a radiologist using ultrasound,
fluoroscopy, a CT scan, or
magnetic resonance imaging (MRI) to help guide the
You will need to take off all or most of your
clothes. You will wear a gown. Before the biopsy, you may be given a sedative
intravenous (IV) line in a vein in your arm. The
sedative will help you relax and lie still during the biopsy.
During the test
will be asked to lie on an examination table. A sandbag, a firm
pillow, or a rolled towel will be placed under your body to support your belly.
It is very important that you follow your doctor’s directions about breathing,
holding your breath, and lying still while the biopsy is being done.
Your doctor will examine your back and may mark the biopsy site by making
a slight dent in your skin with a pencil or tool. The biopsy may be done on
either the right or the left kidney. The site will be cleaned with a special
soap. Your doctor then gives you
local anesthetic to numb the area where the biopsy
needle will be inserted.
Your doctor puts the biopsy needle
through the skin while
looking at your kidney with ultrasound or another imaging technique. You will be
asked to hold your breath and stay very still while the needle is put into the
The needle is removed after the tissue sample is taken.
Pressure is put on the biopsy site for several minutes to stop the bleeding.
Then a bandage is put on the site. The biopsy takes 15 to 30 minutes.
After the test
After the biopsy, you will rest in bed for 6 to 24 hours. Your pulse,
blood pressure, and temperature will be checked often after the biopsy.
If no problems develop, you can go home. To prevent bleeding at the
biopsy site, you will be told to lie down in a certain position for the next 12 to 24 hours. You may eat
your normal diet. Do not take aspirin or anti-inflammatory medicines for a week
after the biopsy. You may do your regular activities, but do not do strenuous
activities, such as heavy lifting, hard running, motorcycle riding, contact
sports, or other activities that might jar or jolt your kidney, for 2 weeks
after the biopsy.
How It Feels
You may feel a brief sting or pinch when
the numbing medicine is put in. When the biopsy needle is put in, you may feel
a sharp pain for a few seconds.
It is normal to feel some muscle
soreness in the area of the biopsy for 2 to 3 days after the biopsy. You may
have a small amount of bleeding on the bandage after the biopsy. Talk to your
doctor about how much pain and bleeding you can expect. Many people will have
bright red blood in their urine for the first 24 hours after the biopsy; this
There is a small chance for serious problems
from a kidney biopsy, but they are rare.
- Bleeding into the muscle, which can cause soreness.
- Bleeding into the kidney.
- Infection of the skin at the biopsy site.
- Pneumothorax (collapsed lung).
- Puncturing a major blood vessel, which may need
blood transfusions, renal angiography and
embolization, or surgery. This is very rare.
After the biopsy
After the biopsy,
call 911 or other emergency services immediately if you develop:
- Signs of
shock, such as passing out, or feeling very dizzy, weak, or less alert.
- Severe pain in your chest, shoulder, or belly.
- Moderate to severe difficulty breathing.
After the biopsy, call your doctor immediately if you:
- Develop more pain in your back, belly, or groin.
- Have too much bleeding or drainage (such as pus) from the
- Have blood in your urine for longer than 24 hours after the
- Have signs of an infection, such as a fever or burning when you urinate.
- Have weakness or lightheadedness when you change position, such
as standing up from a sitting or lying position.
biopsy is done by inserting a long needle through the
back (flank) or belly to remove a sample of kidney tissue.
Biopsy results are ready in 2 to 4 days. If tests are done
to find infections, it may take several weeks for the results to be
The structure and cells of the
The sample may show signs of
Kidney tissue may show tumors
Kidney tissue shows signs of transplant reactions, rejection, or failure.
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include:
- Having an untreated bleeding or blood clotting disorder.
- Not being able to lie still.
- Having advanced kidney disease, uncontrolled
high blood pressure, or only one kidney.
- Having a severely deformed spine.
- Having a
urinary tract infection.
What To Think About
- A kidney biopsy is done after other tests for kidney disease
(such as blood and urine tests,
ultrasound, and a
CT scan) have not been able to tell what kind of
kidney problem is present. A kidney biopsy has more risk for problems than
these other tests and a chance of
false-negative results. More than one biopsy may be
- Open kidney biopsy and ureteroscopy are two other methods that
may be used to take kidney tissue samples. You will stay overnight in the
hospital for these biopsies.
- An open kidney biopsy is a surgery done in an operating room
while you are asleep (general anesthesia). A cut (incision) is made through the back or the side and a
small piece of kidney tissue is taken out. Open biopsy is often done when the doctor needs to remove a larger piece of tissue (such as a tumor).
- Ureteroscopy with biopsy is often done if there is a mass in
the renal pelvis or ureter. Ureteroscopy is a surgery done in an operating room
under spinal or general anesthesia. A long thin flexible tube (ureteroscope) is
used to look inside the ureter and lower part of the kidney (renal pelvis).
Once the mass is found, a biopsy is done through the ureteroscope.
- An open kidney biopsy is a surgery done in an operating room
Other Works Consulted
- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby’s Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Primary Medical Reviewer E. Gregory Thompson, MD – Internal Medicine
Adam Husney, MD – Family Medicine
Specialist Medical Reviewer Christopher G. Wood, MD, FACS – Urology, Oncology
Current as ofOctober 9, 2017