Kidney Biopsy
Kidney biopsy is an important test useful in the diagnosis of certain
kidney diseases such as glomerulonephritis, certain tubulointerstitial
diseases, etc.
What is kidney biopsy?
During a kidney biopsy, a small piece of kidney tissue is removed through
a needle and examined under a microscope. Kidney biopsy is performed
to diagnose the exact nature of certain kidney diseases, e.g.
glomerulonephritis and certain tubulointerstitial diseases, etc.
When is kidney biopsy advised?
In certain kidney diseases even a detailed history, physical examination
and routine tests are unable to establish proper diagnosis. In such
patients, a kidney biopsy may provide additional information, which
can establish the correct diagnosis.
How does the kidney biopsy help?
The kidney biopsy establishes specific diagnosis of certain unexplained
kidney diseases, e.g. glomerulonephritis and certain tubulointerstitial
diseases, etc. With this information, the nephrologist is able to plan
effective treatment strategy and guide patients and their family about
the severity and course of the disease.
By which technique is a kidney biopsy performed?
The most common method is via a percutaneous needle biopsy (usually
performed in the radiology suite), in which a hollow needle is passed
through the skin into the kidney. Another rarely used method is open
biopsy which requires surgery (performed in the operating room).
The kidney biopsy is a test performed to establish the diagnosis of certain kidney
diseases, glomerulonephritis certain tubulointerstitial diseases etc.
How is a kidney biopsy performed?
- The patient is admitted in hospital and his consent is obtained.
- Prior to biopsy it is ensured that blood pressure and blood tests on
blood clotting are within normal. Medications used for the prevention
of blood clotting (e.g. aspirin and clopidrogel) is recommended to
be discontinued for at least 1- 2 weeks prior to biopsy.
- Ultrasound or CT scan is done to know the position of kidneys and
to determine exact biopsy site.
- The patient is asked to lie face down – on his/her stomach with the
abdomen supported by a pillow or towel. The patient is fully awake
during the procedure. In small children the kidney biopsy is done
under general anesthesia, so the child is not awake.
- After proper cleaning of the skin, the biopsy site is numbed with
local anesthesia to minimize discomfort and pain.
- With the use of a hollow biopsy needle, 2 or 3 small thread like
pieces are obtained from the kidney. These specimens are then sent
to the pathologist for histopathology examination.
- After the biopsy, pressure is applied to the biopsy site to prevent
bleeding. The patient is put on complete bed rest for 6-12 hours and
usually discharged the following day.
- The patient is advised to avoid heavy work or exercise for at least
2-4 weeks after the biopsy procedure.
Are there any risks to kidney biopsy?
Like any surgical procedure, complications can occur in a few patients
after kidney biopsy. Mild pain or discomfort over the puncture site and
passing of reddish urine once or twice is not uncommon, but it usually
stops on its own. In rare cases where bleeding continues, blood
transfusion may be required. In extreme and very rare circumstances
where by intractable severe bleeding persists emergency removal of
kidney by surgery may become necessary.
Sometimes kidney tissue obtained may not be adequate for diagnosis
(about 1 in 20). Repeat biopsy may be needed in such cases.
The kidney biopsy is usually performed with the use of a
thin hollow needle with the patient in the fully awake state.