A kidney 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?).