Kidney Biopsy Test: Procedure, Risks, Indications, Video, Result

A kidney biopsy, or renal biopsy, is the test doctors use to diagnose kidney diseases and conditions. The kidney biopsy procedure involves removing a small piece of tissue from the kidney to examine it under a microscope for signs of damage. Usually, the procedure is performed in hospitals or outpatient clinics. 

Anatomy and Physiology of Kidney

Kidneys are two bean-shaped organs below the rib cage on each side of the spine. They remove waste from the body, balance electrolyte levels, and regulate blood pressure.   

1. The right kidney is slightly lower than the left to make room for the liver. 
2. Each kidney is surrounded by a tough, fibrous renal capsule that supports the soft tissue inside. 
3. The kidney consists of several pyramid-shaped lobes, with the renal cortex (outer layer) and the renal medulla (inner part of the kidney). 
4. Nephrons begin at the renal cortex.
5. Each nephron includes a filter (glomerulus) and a tubule. 
6. The glomerulus filters the blood that enters the kidneys through the renal arteries and leaves the kidneys through renal veins. 
7. The tubule provides necessary substances to the blood and removes waste that becomes urine. 
8. Urine is excreted from the kidneys through the ureter, which attaches to the bladder.

If routine urine and blood tests indicate that the patient’s kidney is not working properly, the doctor may decide to perform a kidney biopsy. The reasons for kidney biopsy include:

1. Diagnose a kidney problem that couldn’t be identified otherwise.
2. Identify the cause of abnormal levels of waste products in the blood.
3. See if a kidney tumour is malignant or benign.
4. Determine the progression of kidney disease.
5. Determine the extent of damage caused by kidney disease.
6. Find how well a transplanted kidney is working.
7. Evaluate how well the treatment for kidney disease is working.
8. Help develop treatment plans for a diseased kidney.

A kidney biopsy helps healthcare professionals identify the cause of a patient’s kidney problems to devise an effective treatment plan. The doctor may recommend a kidney biopsy test if the patient has the following:

1. A transplanted kidney
2. Hematuria: blood in the urine
3. Proteinuria: protein in the urine
4. Abnormal results from a blood test
5. Glomerulonephritis: damage to the filters inside the kidney
6. Kidney disease with no known cause

Usually, a kidney biopsy is performed as an outpatient procedure in a procedure room at a hospital. Sometimes, it may be done in the radiology department if a CT scan or an ultrasound is needed during the procedure.

The complete procedure of kidney biopsy usually lasts about an hour. There are two types of kidney biopsy: 

1. Percutaneous Biopsy: This is a more common type of kidney biopsy procedure in which the doctor numbs the skin over the kidney and inserts a biopsy needle to take a tissue sample.
   The doctor uses ultrasound imaging to guide the needle to the correct location. Further, the doctor may use one of the following types of percutaneous biopsies:
   1. Fine needle aspiration biopsy: In this procedure, the surgeon extracts a small sample of kidney tissue using a small, thin needle attached to a syringe.
   2. Needle core biopsy: In this procedure, the surgeon extracts a larger tissue sample using a spring-loaded needle.
2. Open Biopsy: This is a rare type of biopsy usually performed during a kidney transplant. It is also performed when the patient has had bleeding or blood-clotting problems. In an open biopsy, the doctor makes an incision to remove tissue from the kidney. 

Please note: The selection of the kidney biopsy procedure is based on the patient’s health condition and the doctor’s opinion. 

The general steps in the kidney biopsy procedure include the following:

1. The patient will be made to lie on their stomach on the operating table. They will be told to lie on their back if they already had a kidney transplant. 
2. The anaesthesiologist will start an intravenous line in the patient’s hand or arm for fluids and medications. 
3. He/she will administer local anaesthetic to numb the area for percutaneous biopsy and general anaesthesia for open biopsy. 
4. The nursing team will clean the biopsy site with an antiseptic solution. 
5. The anaesthesiologist will monitor the patient's vitals throughout the procedure.

Percutaneous Biopsy

1. The surgeon will make a cut or incision at the surgical site and insert the needle through the incision into the patient’s kidney. He/she might use a CT scan or ultrasound to direct the kidney biopsy needle. 
2. The patient will have to take a deep breath and hold it for 30-45 seconds as the physician takes the tissue sample.
3. The process will be repeated several times if more tissue is needed.  
4. The surgeon will remove the needle and apply firm pressure to the biopsy site to stop bleeding. 
5. The team will place a small bandage or dressing on the incision.

Open Biopsy

1. While the patient is unconscious, the surgeon will make an incision and surgically remove a kidney tissue sample using a spring-loaded needle.
2. The surgeon will use stitches to close the incision and place a bandage on the wound.  

The sample of kidney tissue will then be sent to a lab for testing.

The doctor provides several instructions to the patient before the procedure. The patient will be informed about the dos and dont’s of preparation for kidney biopsy. 

Before Kidney Biopsy Test

Here’s what happens before the test:

1. Consultation and Evaluation
   1. The patient will undergo a pre-anaesthetic checkup.
   2. The doctor will assess the patient’s medical history.
   3. Before the kidney biopsy, the patient may undergo blood and urine tests to look for preexisting infections. 
   4. Based on the diagnostic tests, the doctor will decide the type of kidney biopsy.
   5. Based on the PAC results and the type of test, the anaesthesiologist will decide on the anaesthesia to be administered. 
   6. The patient must inform the doctor about all their prescription drugs, over-the-counter medications, and herbal supplements. 
   7. They must also inform the doctor if they are pregnant or might be pregnant. 
   8. The doctor will briefly explain the procedure, duration, cost, etc. 
2. Restrictions
   1. The doctor will ask the patient to stop taking certain medications, such as blood thinners, non-steroidal anti-inflammatory drugs (NSAIDs), herbal or dietary supplements, and medications that affect blood clotting.
   2. The patient must stop eating and drinking for at least eight hours before the kidney biopsy.  

On the Day of the Kidney Biopsy Test

1. The patient can expect the following on the day of the test:
2. The patient must arrive at the hospital before the scheduled time. 
3. He/she will be asked to sign consent formalities. 
4. The patient will change into a hospital gown before the procedure. 
5. The doctor will record the last meal of the patient. 
6. He/she may give a sedative to help the patient relax. 
7. The anaesthesiologist will monitor the patient’s vitals, such as blood pressure, breathing, and heart rate. 
8. The team will shift the patient to the procedure or radiology room.

Since a kidney biopsy is performed as an outpatient procedure, the patient can go home the same day. The following is what a patient can expect during hospital and home recovery. 

The recovery process in the hospital

1. After the procedure, the patient will be moved to the recovery room for rest and observation. 
2. The patient will lie on their back (or on their stomach if they have had a kidney transplant) for about six to eight hours. 
3. The anaesthesiologist will monitor the patient’s vital signs and the effect of anaesthesia. 
4. The patient will undergo urine and blood count tests to look for internal bleeding or other complications. 
5. He/she will be given medication to reduce pain at the surgical site. 
6. The patient gets released from the hospital when their vital signs are stable, usually 12 to 24 hours after the procedure. 
7. The doctor will provide homecare instructions.
8. The patient may need someone to drive them home after the procedure. 

Recovery process/expectation after hospital discharge

The patient must follow all aftercare instructions provided by the doctor. It is normal to have bright red blood in the urine for 24 hours after the kidney biopsy. Complete recovery may take about two to three weeks. 

1. Wound Care
   1. Do not shower for 24 hours. The patient may use a sponge or a washcloth. 
   2. The patient can shower after 24 hours but should not scrub the biopsy site. 
   3. Wash the area and pat it dry. 
   4. Do not submerge in a bath, hot tub, or swimming pool for three days.  
   5. Remove the bandage from the surgical site 24 to 48 hours after the procedure. 
2. Activities to Do
   1. Rest for 24 to 48 hours after the procedure. 
   2. Start with a light walk, increasing the amount of walking every day. 
3. Restrictions
   1. Don’t drive for about 24 to 48 hours. 
   2. Avoid strenuous activities and heavy lifting for two weeks.  
   3. Avoid aerobics, jogging, or other activities that require bouncing for two weeks. 
4. Medicine
   1. Take pain relievers for discomfort as prescribed by the doctor. 
   2. Do not take anti-inflammatory medications for a week after the biopsy. 
   3. If patients stopped taking blood thinners before the procedure, they should ask the doctor when to start retaking them. 
5. Diet
   1. The patient can resume their regular diet. 
   2. If their stomach is upset, they should try bland food like boiled chicken, plain rice, toast, and yoghurt. 
   3. Drink plenty of fluids to avoid dehydration. 

First Follow-Up Appointment

Follow-up care is a vital part of the kidney biopsy procedure.

The first follow-up appointment is generally scheduled three to five days after the procedure when the physician receives the test results. During the appointment, the doctor will monitor the patient for possible complications and offer further instructions.

The kidney tissue sample collected during the biopsy is sent to a laboratory for examination by a pathologist. The pathologist analyses the sample with reactive dyes under a microscope to detect scars, infections, and other abnormal conditions.

A kidney biopsy report is usually ready within three to five days.  

1. The results are considered normal if the tissue from the kidney shows a standard structure without deposits and defects.
2. The results are considered abnormal if there are changes in the kidney tissue.
   Abnormal results can indicate conditions like a kidney infection, kidney cancer, connective tissue disorders, rejection of a kidney transplant, restriction in blood flow to the kidney, etc.

Kidney biopsy is an effective procedure that helps doctors diagnose kidney conditions. The benefits of a kidney biopsy include the following:

1. It helps detect the fault in the kidneys.
2. It offers a correct treatment approach for the procedure.
3. It helps avoid unnecessary treatments.
4. The procedure prevents side effects that may occur due to the wrong treatment. 
5. Percutaneous biopsy with a needle is less invasive, leaves no scar, and takes less than an hour to perform.

Generally, kidney biopsy is a safe procedure. Some possible kidney biopsy risks include:

1. Bleeding: The most common risk of kidney biopsy is blood in the urine. It usually stops within a few days. Bleeding requiring blood transfusion or surgery is rare. 
2. Pain: While pain is a common side effect after the procedure, it usually lasts only a few hours.  
3. Arteriovenous fistula: An irregular connection between an artery and vein forms when the kidney biopsy needle accidentally damages the walls of these blood vessels. It usually causes no symptoms and closes on its own. 
4. Haematoma: Blood collection around the kidney is a rare complication after a kidney biopsy. It is treated with antibiotics and surgical drainage. 
5. Infection: Infection near the biopsy site rarely happens after a biopsy. 

When is consultation with the doctor needed?

The patient should call their healthcare professional if they experience the following kidney biopsy side effects:

1. Significant bright red blood in the urine for more than 24 hours.
2. Worsening pain at the biopsy site.
3. Changes in urination (inability to urinate, a frequent urge to urinate, or a burning sensation while urination).
4. Fever over 100.4℉.
5. Swelling, redness, or bleeding from the biopsy site.
6. Weakness or faintness.

Kidney biopsy cost in India ranges from ₹5,000 to ₹20,000. The cost of the procedure may vary depending on several factors, some of which include:

1. Patient’s overall health
2. The method used for tissue removal
3. Type of hospital
4. Surgeon’s experience and expertise
5. Pre-procedure tests
6. Consultation fees
7. The city where the test is performed

The following is the cost breakup of the kidney biopsy procedure: