How Are Kidney Stones Treated
Fortunately, most stones will pass without surgery. Most stones can pass through the urinary tract system with water…about 2-3 quarts a day will help the stone move through your system. Often times, the patient can stay home during this process, drinking fluids and taking pain medication. The doctor will usually ask that the stone be saved for analysis purposes.
If you have a stone that will not pass by itself, your doctor may need to take steps to get rid of it. In the past, the only way to remove a problem stone was through surgery. Now, we have new ways to remove problem stones without surgery.
But first let’s talk about …
How are kidney stones diagnosed?
Kidney stones are almost always diagnosed nowadays with a CT scan. The scan requires or oral or intravenous contrast or dye. It takes 20 seconds (on breath hold). We also frequently obtain a plain x-ray of the abdomen, called a KUB for Kidney Ureter Bladder, to document how the stone looks on a plain x-ray. This is helpful for 2 reasons. It gives us a simple imaging modality to use in a week or two to see if the stone has passed or moved. It is also often important for us to know how well the stone shows up a plain x-ray, because if we do ESWL (see below) we have to be able to see the stone on a KUB. If we can’t see it on KUB, we have to use a different technique to get rid of the stone.
How will your doctor find out what kind of stone you have?
The best way for your doctor to find out what kind of stone you have is to test the stone itself. If you know that you are passing a stone, try to catch it in a strainer. Your doctor may ask for a urine sample or take blood to find out what caused your stone. You may need to collect your urine for a twenty-four hour period. These tests will help your doctor find ways for you to avoid stones in the future.
Why do you need to know the kind of stone?
The therapy your doctor gives you depends on the type of stone you have. For example, a medicine that helps prevent calcium stones will not work if you have a struvite stone. The diet changes that help prevent uric acid stones may not work to prevent calcium stones.
Therefore, careful analysis of the stone will help guide your treatment.
Removing kidney stones
A stone may need to be removed if it:
- Doesn’t pass after a reasonable amount of time
- Causes constant pain over an extended period
- Causes an ongoing urinary tract infection
- Is too large to pass on its own
- Has grown larger, as seen on a x-ray
- 30 years ago, the only option to remove a kidney stone was open surgery, with a recovery time of four to six weeks. We almost never make an incision to remove a stone now.
Lithotripsy (Extracorporeal shock wave lithotripsy–ESWL)
Lithotripsy has been used for 25 years for the treatment of kidney stones. Under anesthesia, we use x-rays to find the stone and put it in the focal point for a shock wave generator which is beneath the operating room table. We then typically deliver 1000-3000 shocks to the stone, monitoring the fragmentation of the stone on fluoroscopy (x-ray). The shock waves are painful, which is why you need anesthesia. The shock waves also cause some bruising of the kidneys, but studies have shown that a month later there is no permanent damage. Enough bleeding to require a transfusion is rare, about 1 in 600 cases, but because of this you cannot take aspirin, NSAIDs (nonsteroidal anti-inflammatory drugs) or any blood thinners for a week before lithotripsy.
Ureteroscopic stone removal
More commonly, we need to remove the stone under direct vision. We do this, also under anesthesia, by passing a small scope through the urethra and bladder and up the ureter to the stone. Sometimes we can pull it out intact. Often the stone is too big to remove intact. In those cases we use a laser to vaporize it (like on Star Trek) on break it up into little pieces which we then pull out.
We often will need to put in a ureteral stent when we do ureteroscopy or lithotripsy. These are small (2 mm diameter) hollow silicone tubes which we put inside the ureter, from the bladder all the way up to the kidney to keep the ureter from swelling shut or to prevent stone fragments from lithotripsy from obstructing the ureter. Usually we retrieve the stent about a week later in the office by passing a small flexible cystoscope into the bladder. The stent may cause some pain, although not usually the severe pain that the stone did. It may irritate you bladder some and it usually causes you to have some blood in the urine. For the last 2 years, we have been using a new brand of stents which most people seem to tolerate better than the older ones.
Some stones in the kidney are too large to remove with a ureterosocope and too large to treat with ESWL—there would be too many fragments to pass. In these cases, we place a tube through the back into the kidney and use a scope to break the stone up with ultrasound or a laser and remove the fragments. Post operatively we leave a tube (nephrostomy tube) in place to drain the urine for a few days. Stones that are very large may require more than one procedure to remove in their entirety.
Lifestyle changes—How to avoid more stones
The simplest and most important lifestyle change a person can make to prevent stones is to drink more liquid … preferably water. If you are susceptible to kidney stones, you should drink enough water to create 2 quarts of urine in a 24-hour period.
In the past, we thought that people who consumed large amounts of dairy products and other foods high in calcium were at a higher risk for kidney stones. But recent studies have shown that food high in natural calcium may actually help prevent kidney stones … although taking calcium in pill form has been shown to increase the risk of developing stones.
Some people may be told to avoid foods with added vitamin D and certain types of antacids that have a calcium base. People who have high acidic urine may need to eat less meat, fish, and poultry. These foods increase the amount of acid in the urine…leading to kidney stones.