Kidney stones are a common and painful condition. They can cause severe back or abdominal pain, blood in the urine or common urinary tract infections.
Kidney stones are caused by a lack of water, too much salt, too much animal protein in the diet or a lack of stone inhibitors created by the kidneys. Up to 90 percent of kidney stones will pass out of the body on their own in the urine. However, patients with stones that block the flow of urine from the kidney can lose the funtion of their kidneys or have severe infections, which can lead to death.
Patients with one kidney stone have a 60 percent chance of having another one in the future. The Department of Urologic Surgery at Vanderbilt University Medical Center gives kidney stone patients a medical evaluation and offer a variety of treatments to help prevent more stones. We also suggest changes to the patient's diet and medications, which may also lower the risk of new stones.
To help avoid kidney stones, drink at least two quarts (64 oz.) of water per day, reduce the amount of salt (sodium) you eat and drink; and limit the amount of animal protein in your diet.
A non-surgical way to treat kidney stones is shock wave lithotripsy (SWL):
For kidney stones smaller than one inch in size, or for multiple stones in the ureter (one of the tubes that takes urine from the kidneys to the bladder), SWL can be a very effective treatment. This procedure uses shock waves that are created by a machine outside the body. X-ray or ultrasound shock waves turn kidney stones into sand or tiny gravel, which can then pass out through the urine.
This can be done as an outpatient procedure, meaning there's no need to spend a night in the hospital, and patients usually return to regular activities within a few days of the treatment. It is normal to have blood in the urine for several days after SWL. Blockage of urine flow from the kidney can occur in less than 10 percent of patients, while the stone fragments pass. If this causes severe pain or kidney blockage, a tube may be placed through the back into the kidney to keep it drained until the fragments all pass out of the ureter.
There are several surgical treatments for kidney stones:
Percutaneous Nephrolithotomy (PCNL)
Some patients form large kidney stones that are related to a bacterial infection. These stones are usually on the inside of the kidney and cause blockage and swelling of the kidney tissue. An operation is usually required to remove all of the stones, which contain the source of the bacteria infection.
The percutaneous nephrolithotomy (PCNL) is an operation to remove large stones from the kidney. This operation involves inserting a tube through a one-inch incision in the back and into the kidney. An instrument is threaded through the tube to look inside the kidney and see the stone. An ultrasound probe or laser fiber is inserted through the instrument and used to break up the stone and pull it out of the kidney. Removing all of the stone fragments relieves the kidney blockage, improves kidney function and helps stop the infection and the growth of new stones.
Small kidney stones may drop into the ureter (the tube that drains urine from the kidney to the bladder) and cause pain and blockage of the urine flow from the kidney. An operation called a ureteroscopy can be used to treat stones in the ureter. In this operation, a small instrument is passed through the urethra (the tube from the bladder to the outside of the body) through the bladder and up the ureter into the kidney. Devices can be inserted through the instrument to break up stones in the kidney or the ureter or take samples of tissue to rule out cancer. These devices can also stop any bleeding in the kidney or cut out scar tissue blocking the ureter.
After ureteroscopy, a stent (a small tube that passes from the kidney, down the ureter to the bladder) is typically left inside the body for several days to weeks. This stent helps drain the kidney, but also causes blood in the urine and some discomfort in the bladder and back. Once the stent is removed, these symptoms will disappear in one or two days. The ureteroscopy can usually be performed as an outpatient procedure or it may require one night in the hospital. There is much less discomfort with ureteroscopy compared with an open side incision, and the patient can get back to regular activities within a few days or a week of the procedure.