Last week, we talked about kidney stones, focusing on the causes and symptoms. Today we'll talk about how kidney stones are diagnosed and treated.
How is the diagnosis made?
Diagnosis always starts with a good medical history and physical exam. If your doctor believes you could have a kidney stone, here are the tests that might be done to make the diagnosis:
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Urinalysis - To look for blood in the urine, which is usually present with kidney stones.
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High-resolution CT scan of the kidneys down to the bladder - This is the preferred test for diagnosis. It can show even tiny stones. It also shows if the stone is blocking the flow of urine.
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KUB X-ray - This is an X-ray that shows the kidney, ureter, and bladder. It can show the size and position of a kidney stone. It is not often used for diagnosis of a stone because it can miss some smaller stones. However, it may be used to help determine if the stone is suitable for shock-wave treatment or to monitor a kidney stone before and after treatment.
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Intravenous Pyelogram (IVP) - This is a special type of X-ray of the urinary tract that is done after an injection of dye. Although it is still occasionally used, with the availability for high-resolution CT scans, this test is not done very often anymore.
What other tests might be done?
After a kidney stone is diagnosed, your doctor may want to do other tests to determine what type of stone it is, or if there are any underlying conditions that have caused you to develop stones.
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Blood tests - Testing for calcium levels and uric acid levels is usually done. If calcium levels are high, you may have additional blood tests to check your parathyroid hormone levels.
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Urine tests - A 24-hour urine collection can show if you have too many stone-forming minerals in the urine or too few stone-preventing chemicals.
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Stone analysis - Your doctor may ask you to urinate through a strainer to try to catch the stone that you pass. This stone can then be sent to the lab to determine the makeup of the stone.
How are kidney stones treated?
Treatment depends on many things, including how large the stone is, whether there is potential damage to the kidney from urine backup, or whether you have a urinary tract infection.
If you have a small stone, treatment may include:
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Drinking plenty of water - Up to 2-3 quarts a day.
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Medications for pain - The pain from small stones usually responds well to ibuprofen or naproxen. Occasionally, stronger pain medications are necessary.
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Other medications - Sometimes medications are given to relax the muscles in the ureter (the tube from the kidney to the bladder where most stones get stuck). This can help you pass the stone more quickly with less pain.
If you have a large stone, that is too large to pass on its own, treatment may include:
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Shock wave treatment - Also called lithotripsy or ESWL. This treatment uses sound waves to create strong vibrations that can break the stone into tiny pieces, which can then be passed in your urine.
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Using a scope to remove the stone - If the stone is not too large, it can be removed with a lighted tube that is passed through your urethra and bladder. A snare is passed through this tube to pull the stone out through the tube.
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Laparoscopic surgery - Very large stones may require surgery through a small incision in the back, through which small instruments are passed to remove the stone. This is done under general anesthesia.
Can kidney stones be prevented?
You can reduce your risk of developing kidney stones by doing the following:
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Drink plenty of water throughout each day
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Eat fewer food that are rich in oxalates - This includes rhubarb, beets, okra, spinach, Swiss chard, sweet potatoes, nuts, tea, chocolate, black pepper, and soy products.
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Eat a diet low in salt and animal protein
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Continue to eat foods that are rich in calcium but avoid calcium supplements unless your doctor recommends them.
There are also some medications that can be prescribed by your doctor to prevent stones. If you have frequent kidney stones, your doctor might recommend one. The medication used will depend on the type of kidney stones that you make.
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Dr. Anita Bennett MD - Health Tip Content Editor