Kidney Biopsy

A biopsy is a test that involves collecting small pieces of tissue, usually through a needle. The tissue is then examined under a microscope. A kidney biopsy can help find a diagnosis and determine the best course of treatment. Your caregiver may recommend a kidney biopsy if you have any of the following conditions:

  • Hematuria. This is blood in your urine.

  • Proteinuria. This is when there is excessive protein in your urine.

  • Impaired kidney function that causes excessive waste products in your blood.

A specialist will look at the kidney tissue samples to check for unusual deposits, scarring, or infecting organisms that would explain your condition. Your caregiver may discover that you have a condition that can be treated and cured. If you have progressive kidney failure, the biopsy may show how quickly the disease is advancing. A biopsy can also help explain why a transplanted kidney is not working properly. Talk with your caregiver about what information might be learned from the biopsy and the risks involved. This can help you make a decision about whether a biopsy is worthwhile in your case.

BEFORE THE PROCEDURE

  • Make sure you understand the need for a biopsy.

  • Tell your caregiver about any allergies you have and medicines you take.

  • Avoid food and fluid for 8 hours before the test.

  • You will have to sign a consent form indicating that you understand the risks involved in this procedure. They are very rare. Discuss these risks thoroughly with your caregiver before you sign the form.

  • Make sure your caregiver is aware of all the medicines you take and any drug allergies you might have. Shortly before the biopsy, you will give blood and urine samples. This is to make sure you do not have a condition that would suggest not doing a biopsy.

PROCEDURE

  • Kidney biopsies are usually done in a hospital. You may be fully awake with light sedation or you may be asleep under general anesthesia. If you are awake, you will be given a local anesthetic before the needle is inserted.

  • You will lie on your stomach to position the kidneys near the surface of your back. If you have a transplanted kidney, you will lie on your back. The doctor will inject a local painkiller. For a through the skin (percutaneous) biopsy, the doctor will use a locating needle and X-ray or ultrasound equipment to find the right spot and then a collecting needle to gather the tissue. You will be asked to hold your breath as the doctor inserts the biopsy needle and collects the tissue. This is usually for about 30 seconds or a little longer for each insertion. Do not exhale until you are told.

  • The entire procedure usually takes an hour. This includes time to locate the kidney, clean the biopsy site, inject the local painkiller, and obtain the tissue samples.

  • Some patients should not have a percutaneous biopsy if they are prone to bleeding problems. These patients may still undergo a kidney biopsy through an open operation. This is when the surgeon makes an incision and can see the kidney to obtain a biopsy.

AFTER THE PROCEDURE

  • You will lie on your back for 12 to 24 hours. During this time, your back will probably feel sore. If you have a transplanted kidney, you will lie on your stomach. You may stay in the hospital overnight after the procedure so that staff can check your condition. You may notice some blood in your urine for 24 hours after the test. To detect any problems, your caregivers will:

  • Monitor your blood pressure and pulse.

  • Take blood samples to measure the amount of red cells.

  • Examine the urine that you pass.

  • On rare occasions when bleeding does not stop on its own, it may be necessary to replace lost blood with a transfusion.

  • A rare complication is infection from the biopsy procedure.

SEEK MEDICAL CARE IF:

  • You have bloody urine more than 24 hours after the test.

  • You have a fever.

  • You feel faint or dizzy .

  • You cannot urinate .

  • You have worsening pain in the biopsy.

OBTAINING THE TEST RESULTS

It is your responsibility to obtain your test results. Ask the lab or department performing the test when and how you will get your results.

FOR MORE INFORMATION

  • American Kidney Fund: www.akfinc.org

  • National Kidney Foundation: www.kidney.org

  • National Kidney and urologic Diseases Information Clearinghouse: http://kidney.niddk.nih.gov/