Renal Biopsy - Things You Should Know About It!

Kidneys play an important metabolic role and are essential for balancing salt, minerals and water in the body. They also play a significant role in removing waste products from the body. They make urine, which contains all the waste materials that are eliminated from the body. They also play an important role in blood pressure regulation and in maintaining the balance of various minerals in the body. Any suspected kidney damage should be confirmed by a kidney biopsy, which will reveal the exact disease, thereby directing towards the appropriate treatment. 

Why and when is it done? 

A renal or kidney biopsy is done in the following situations: 

1. When there is abnormal protein in the blood or urine, which is indicative of a kidney disease, and the exact cause needs to be found out
2. When kidney failure is suggested by blood tests but cause is not clear 
3. To find the cause of bleeding in the urine (haematuria) 
4. To identify and/or confirm diagnosis after a CT scan or ultrasound 
5. To check how well a transplanted kidney has been received 

Know about the procedure 

A renal biopsy is mostly done as an outpatient procedure and is a type of biopsy known as percutaneous biopsy (biopsy where a needle is inserted through the skin into the renal tissue). Very rarely, it may be combined with the CT scan or ultrasound and be done in the radiology department. This may be done on inpatients. The patient is made to lie on his/her back and a local anesthetic is used on the area of the injection. A thin, long needle is directed towards the area of the kidney from where some kidney tissue is removed for sampling.

In some cases, the direction of the needle may be decided by a CT scan or ultrasound. While this is a closed biopsy procedure, in some cases, as a part of the surgery, open biopsies may also be obtained, where a sample of tissue is extracted for analysis. 

Recovering from a biopsy 
The person would need some time to recover from the procedure, as there would be some discomfort at the site of a needle insertion. Vital signs would be monitored for the next couple of hours during which the person would also be monitored for internal bleeding. A pain reliever can be used if required. Haematuria or blood-tinged urine can be seen disappearing within the next 12 hours. Very rarely the bleeding can be severe and require angiography and further procedures. The person should also avoid strenuous activities for the next few days.