Kidney Stones Overview

Kidney stones are exceptionally common, affecting nearly one in every ten Americans. Those who have suffered from stones in the past, or who know someone else who has, understand that stones can be incredibly painful when they start to pass.  Our team of stone experts at Washington University offers advanced care for the treatment and prevention of stone disease.

Below, you will find information about stone disease, links discussing treatment and prevention options available to our patients, and frequently asked questions about stone disease.

Symptoms associated with kidney stones
When a kidney stone starts to pass, symptoms typically occur suddenly and without warning. Sharp, stabbing pain usually develops in your side or back, typically right at the bottom part of the ribcage. Sometimes, the pain will travel downward into the genital area. Stones that have nearly passed into the bladder may be associated with an intense urge to urinate.

Stone pain typically comes and goes. After an initial period of severe pain, you may feel better for a few hours before developing another attack. Many patients will require medication to help with stone pain.

Nausea and vomiting are also very common and are often a reason for hospital admission during stone attacks. You might also see blood in your urine. This can be unsettling to many patients, but is generally not life-threatening.

The most concerning symptom during a stone attack is fever, which indicates that you may have an infection in addition to a kidney stone. This is a potentially life-threatening combination and requires immediate evaluation and treatment.

Treatment of kidney stones
Kidney stones can be managed in a number of ways, depending upon the size of the stone, your other medical problems, and your overall comfort level. Many small stones will pass with the help of medications, which will keep you comfortable while the stone passes naturally. This process may take a few days to a week or more.

For larger stones, stones that are associated with severe symptoms, or stones that will not pass with medical therapy, surgery is often required.

If you think you have a kidney stone
If you are having severe, unmanageable pain you believe is due to a kidney stone, it is recommended that you seek evaluation promptly. This is especially true if you develop fever or chills, or stop making urine, as both may indicate a life-threatening condition.

We have a very limited number of same-day appointments; therefore, it is likely that you will be directed to the emergency department for rapid evaluation. There, they will obtain scans and labs that will help confirm the diagnosis of kidney stones.  From that information, we can make an informed decision about your treatment.

If you have recently passed a stone, you should have close follow-up with a urologist. Our team of stone experts can accommodate you at any of our clinic locations.

Frequently Asked Questions About Stone Disease
Q.
What causes kidney stones?

A. This is a complex question that is not completely understood. The most important contributing factor is dehydration, which is common among working adults. Urine is a solution, and potential stone-forming particles are typically dissolved in your urine. But, when you get dehydrated, your urine is not able to dissolve as many particles, and stone crystals can form. There are a number of other dietary factors. There can also be problems with your metabolism that may make you more likely to develop stones.

Q. What are kidney stones made of?

A. The most common stones are made of calcium. Other compounds include struvite, which is associated with infections, and uric acid, which is the same material that produces gout attacks.

Q. Are kidney stones and gallstones related?

A. No. Gallstones are mostly made of cholesterol, which is not found in kidney stones.

Q. Why are stones so painful?

A. Contrary to popular belief, the pain is not from the stone itself, but from blockage of urinary flow. This typically occurs when the stone passes from the kidney into the ureter, which is the tube that drains urine from the kidney to the bladder. When the urinary flow is blocked, the urine backs up and stretches the kidney and ureter, which are covered in pain-sensing nerves that respond to stretching forces. This produces the severe pain and nausea often experience with stones attacks.

Q. Do all stones cause pain?

A. No. Stones that are in the kidney and are not blocking urine flow are not painful. Unfortunately, some of these stones can grow quite large and damage the kidney without causing symptoms.

Q. Is severe back pain always due to a stone?

A. No. Other common causes include muscle pain, nerve pain, severe urinary tract infections, and even severe constipation.  Therefore, the diagnosis of kidney stones often requires tests, including labs and X-rays.

Q. Do stones damage the kidney?

A. Potentially, but not always. Kidneys can temporarily lose some of their function when they are blocked by a stone, but in most cases, your kidney will completely recover after the stone is gone. Provided that you are in good health and have normal kidneys, your kidney can tolerate a little over a month of blockage without suffering any permanent damage.

However, large stones, especially those that fill the kidney, or stones that remain untreated after a long time, can cause permanent damage to the kidney, and may lead to kidney loss. This damage often occurs without any symptoms, which is why it is important to see a urologist if you have a stone.

Q. Do all stones require surgery?

A. While many patients will elect for surgical treatment, many small stones can pass without the need for surgery. In these situations, medications that can help your pain and speed up the passage of your stone are usually given. Large stones, or stones that cause other problems, often require surgical treatment.

Q. How long can it take for a stone to pass?

A. With medical expulsive therapy, most small stones (less than 5 or 6 mm) will typically pass within a few days to a few weeks. Provided you are in good health, you can try for up to 6 weeks to pass a stone, although most patients elect for earlier intervention.

Q. I was passing a kidney stone, but now I feel better. I didn’t catch the stone in my urine. Do I still need to see a urologist?

A. Yes. While you may have passed the stone and simply not noticed it in your urine, it is important to know that there are times that your pain might completely resolve, even though the stone is still blocking your kidney.  It is critical that you follow up with a urologist to prevent these silent stones from permanently injuring your kidney.

Q. Are there any special circumstances that require immediate evaluation for kidney stones?

A. Yes. There are several situations in which immediate evaluation is recommended, even if your pain is mild

  • You develop fever or chills.
  • You only have one kidney (born with one kidney or had one removed, for example).
  • You stop making urine.
  • You develop confusion or severe fatigue.
  • You develop severe nausea and vomiting.

Q. If I have formed a stone in the past, am I at risk of forming more stones?

A. Yes. Unfortunately, once you form one stone, your risk of future stones is increased. You have approximately a 50% chance of forming another stone within 5 years. There are some strategies to reduce the risk of forming stones, but at present, there is no way to completely eliminate your risk.

Q. Is there anything I can do to prevent kidney stones?

A. Yes, there are preventive measures that can reduce — but not completely eliminate — your risk of forming stones. Most prevention involves dietary changes, including staying hydrated and avoiding foods that are likely to increase your risk of stone disease. In some circumstances, you may require medication to help reduce your risk of stones. Our stone experts can work with you to find a diet and medication plan to help prevent stones in the future. Unfortunately, no prevention strategy can completely eliminate your risk of developing stones. But, with good medical management, we can significantly reduce the number of stones you will develop over your lifetime.

Q. Does calcium intake or supplementation affect my risk of stones?

A. Typically no. Although it’s true that most stones are made from calcium, for most people, normal dietary intake of calcium and even normal calcium supplementation will not increase your risk of forming kidney stones. In fact, for many stone formers, normal levels of dietary calcium may help to prevent kidney stones.

Q. I have heard that cranberry juice is good for the urinary tract. Is this true?

A. This is a common misconception shared by many people. There is actually little evidence to suggest that cranberry offers protection from urinary tract infections. But, more importantly, cranberry juices and extracts are associated with a significant increase in the risk for kidney stones! So, if you are a stone former, you should avoid cranberry juice!

Q. Anything else I should avoid?

A. Grapefruit juice. One glass of grapefruit juice can nearly double your risk of forming a stone. Also, megadoses of vitamin C (like those sold as cold prevention remedies) can lead to a rapid formation of a kidney stone and should be avoided, as well.

Q. Where do you see patients with kidney stones?

A. We offer clinic consultations and treatment for stone disease at our Barnes-Jewish Hospital and Barnes-Jewish West County Hospital locations. Please call (314) 362-8200 to schedule an appointment with one of our stone experts. 

If you have had an X-ray or CT scan at another hospital, please bring a copy of those films on a compact disc (CD), or arrange to have one sent to our offices. Contact the radiology department where you had the films done to arrange for a CD to be made.