Kidney Biopsies
A kidney biopsy involves taking one or more tiny pieces (samples) of your kidney to look at with special microscopes. The microscopes make it possible to see the samples in greater detail.
The biopsy sample may be taken in one of two ways:
- Percutaneous (through the skin) biopsy: a needle placed through the skin that lies over the kidney and guided to the right place in the kidney, usually with the help of ultrasound.
- Open biopsy: the kidney sample is taken directly from the kidney during surgery.
The kidney sample is then sent to a pathology lab to check for any signs of disease. He or she will check for any signs of disease.
Some kidney problems can often be found with blood and urine tests, a sonogram (an image made by ultrasound) or other special x-rays, and a physical exam rather than a biopsy. But in some patients with certain types of kidney disease, and those with a kidney transplant that is not working well, a correct diagnosis can only be made with a kidney biopsy.
Specific reasons to do a kidney biopsy include:
- Blood in the urine (hematuria) or protein in the urine (proteinuria)
- Abnormal blood test results
- Acute or chronic kidney disease with no clear cause
- Nephrotic syndrome and glomerular disease (which happens when the filtering units of the kidney are damaged)
A kidney biopsy may also help to find:
- If a disease is getting better with treatment or if it is getting worse. It may also show a problem that cannot be cured, but can be slowed down by other therapy.
- How much permanent damage has happened to the kidney.
- Why a transplanted kidney is not working well and helps your doctor decide on further treatment.
- A kidney tumor.
- Other unusual or special conditions.
- If a certain treatment is hurting your kidneys
Your healthcare professional should explain the reasons for the kidney biopsy. You should know why it is necessary, the benefits, and any risks. You will be asked to sign a consent (permission) form to make sure you are aware of any risks. Be sure you understand the risks before you sign the consent form. You may want to write down a list of questions about the biopsy.
In general, percutaneous kidney biopsy is a safe procedure. Possible risks include:
- Bleeding. The most common complication of a kidney biopsy is blood in the urine. The bleeding usually stops within a few days. Bleeding that’s serious enough to require a blood transfusion affects a very small percentage of people who have a kidney biopsy. Rarely, surgery is needed to control bleeding.
- Pain. Pain at the biopsy site is common after a kidney biopsy, but it usually lasts only a few hours.
- Arteriovenous fistula. If the biopsy needle accidentally damages the walls of a nearby artery and vein, an abnormal connection (fistula) can form between the two blood vessels. This type of fistula usually causes no symptoms and closes on its own.
- Others. Rarely, does a collection of blood (hematoma) around the kidney becomes infected. This complication is treated with antibiotics and surgical drainage. Another uncommon risk is the development of high blood pressure related to a large hematoma
A kidney biopsy is usually done in a hospital. An overnight stay may be needed to watch for any problems. You may be awake with only light sedation, or asleep under general anesthesia. You will be lying face down with a pillow under your rib cage. If the biopsy is done on a transplanted kidney, you will be lying on your back.