What is a kidney biopsy?
A kidney biopsy is a procedure that involves taking a small piece of kidney tissue for examination with a microscope. A pathologist—a doctor who specializes in diagnosing diseases—examines the kidney tissue sample in a lab. The pathologist looks for signs of kidney disease or infection. If the kidney has been transplanted and is not working, a kidney biopsy may help identify the cause.
One of the following specialists will perform the kidney biopsy at a hospital or an outpatient center:
- a nephrologist—a doctor who specializes in treating kidney disease
- a urologist—a doctor who specializes in treating urologic and sexual problems
- a transplant surgeon—a doctor who specializes in performing organ transplants
- an interventional radiologist—a doctor who performs procedures using imaging equipment
Why is a kidney biopsy performed?
A health care provider will perform a kidney biopsy to evaluate any of the following conditions:
- hematuria—blood in the urine, which can be a sign of kidney disease or other urinary problems.
- albuminuria—a condition in which the urine has more-than-normal amounts of a protein called albumin. Albuminuria may be a sign of kidney disease.
- changes in kidney function, which can cause the buildup of waste products in the blood.
The kidney tissue sample can show inflammation, scarring, infection, or unusual deposits of a protein called immunoglobulin. If a person has chronic kidney disease—any condition that causes reduced kidney function over a period of time—the biopsy may show how quickly the disease is advancing. A biopsy can also help explain why a transplanted kidney is not working properly.
Health care providers may use a kidney biopsy to diagnose cancer. If cancer is present, there is a small chance that the biopsy needle will spread the cancer. In addition, the biopsy specimen is very small and may miss the cancer and, therefore, may not provide the right diagnosis.
What can a person expect on the day of the kidney biopsy?
A person should arrive 90 minutes to 2 hours before the kidney biopsy to have time for several preliminary procedures, including
- signing a consent form
- having blood tests
- receiving intravenous (IV) fluids and medications