Renal biopsy is usually performed while you are awake, after a cleansing agent is applied, and you are given local anesthesia (numbing medicine) to minimize pain. The most common way to perform a biopsy is to use a needle, which is inserted through the skin and into the kidney.
In most cases, you will have an ultrasound scan so that the clinician knows exactly where to insert the needle. Once the needle is in the right position, the clinician will take a sample of tissue from the kidney with the needle.
After the biopsy, the kidney tissue will be sent to a specialized pathology laboratory and examined with a microscope. This microscopic examination is looking for scars, infection, or abnormalities in the kidney tissue. The results of the microscopic exam are usually available within one to two weeks after the biopsy. In urgent situations, the results can be available within a few hours.
After a needle biopsy, you will be kept in a recovery or an observation unit for several hours to monitor any potential complications, including pain and bleeding. You may have blood drawn or repeat x-rays to monitor for bleeding. In some instances, you could go home after several hours of monitoring. Alternatively, you may be observed in the hospital overnight.
Once it is seemed to be safe for you to go home, you don’t have to perform any heavy lifting or vigorous exercise for one to two weeks. You should continue avoiding aspirin-like drugs or blood thinning medications for at least one week or until your clinician has instructed that it is safe for you.