During a kidney biopsy — also called renal biopsy — your doctor removes a small piece of kidney tissue to examine under a microscope for signs of damage or disease.
Your doctor may recommend a kidney biopsy to diagnose a suspected kidney problem, determine the severity of kidney disease or monitor treatment for kidney disease. You also may need a kidney biopsy if you've had a kidney transplant that's not working properly.
Most often, a doctor performs a kidney biopsy by inserting a thin needle through the skin — a procedure known as percutaneous kidney biopsy. An imaging device helps the doctor guide the needle into the kidney to remove tissue.
During a kidney biopsy, your doctor uses a needle to remove a small sample of kidney tissue for lab testing. The biopsy needle is inserted through your skin and is often directed using the guidance of an imaging device, such as ultrasound.
A kidney biopsy may be done to:
Your doctor may recommend a kidney biopsy based on the results of blood or urine tests that show:
Not everyone with these problems needs a kidney biopsy. The decision is based on your signs and symptoms, test results, and overall health.
In general, percutaneous kidney biopsy is a safe procedure. Possible risks include:
Before your kidney biopsy, you'll meet with your doctor to talk about what to expect. This is a good time to ask questions about the procedure and make sure you understand the benefits and risks.
When you meet with your doctor, bring a list of all medications you take, including over-the-counter medications, vitamins and herbal supplements. Before your kidney biopsy, you'll be asked to stop taking medications and supplements that can increase the risk of bleeding. These include:
Generally, these medications will be stopped 7 days before the procedure and may be resumed 7 days after the procedure. Your doctor or nurse will let you know when to stop taking these medications and supplements, and for how long.
Before your biopsy, you'll have blood drawn and provide a urine sample to make sure you don't have an infection or another condition that would make the biopsy risky.
You may be asked not to drink or eat for eight hours before the kidney biopsy.
You'll have a kidney biopsy at a hospital or outpatient center. An IV will be placed before the procedure starts.
During the biopsy, you'll be awake and lie on your abdomen or your side, depending on which position allows best access to your kidney. For biopsy of a transplanted kidney, most people lie on their backs.
A percutaneous biopsy takes about an hour and includes these steps:
Percutaneous kidney biopsy isn't an option for some people. If you have a history of bleeding problems, have a blood-clotting disorder or have only one kidney, your doctor may consider a laparoscopic biopsy.
In this procedure, your doctor makes a small incision and inserts a thin, lighted tube with a video camera at its tip (laparoscope). This tool allows the doctor to view your kidney on a video screen and remove tissue samples.
After the biopsy, you can expect to:
Most people can leave the hospital the same day. You may need to rest in bed for 12 to 24 hours after the biopsy, as directed by your doctor. Your health care team will let you know about any activity restrictions, such as avoiding heavy lifting and strenuous exercise.
Your kidney tissue goes to a lab to be examined by a doctor who specializes in diagnosing disease (pathologist). The pathologist uses microscopes and dyes to look for unusual deposits, scarring, infection or other abnormalities in the kidney tissue.
Call your doctor if you experience:
Expect your biopsy report from the pathology lab within about a week. In urgent situations, a full or partial report may be available in less than 24 hours. At a follow-up visit, your doctor will discuss the results. The results may further explain what's causing your kidney problem, or they may be used to plan or change your treatment.