When substances in the urine—such as calcium, oxalate, and phosphorus—become highly concentrated, kidney stones can form. People who do not drink enough fluids may also be at higher risk, as their urine is more concentrated. Kidney stones often do not have one specific cause, although some factors may increase your risk.
Identifying the type of kidney stone can help determine the cause and treatment protocol, as well as how to best reduce your risk of getting future kidney stones.
Kidney stones are common. According to the most recent data from the National Institute of Diabetes and Digestive and Kidney Diseases, about 11 percent of men and 6 percent of women in the United States have kidney stones at least once during their lifetime. Men are affected more often than women, and overweight and obese people are more likely to get a kidney stone than people of normal weight.
Risk factors include:
Once you have a kidney stone, you are also more likely to develop a future kidney stones.
The UCLA study “Prevalence of kidney stones in the United States” published in European Urology (PDF) reported on the risk factors that make a person especially likely to develop a kidney stone.
Kidney Stone Symptoms
People with kidney stones may not experience symptoms until the stone moves in your kidney or into your ureter (the tube connecting your kidney and bladder), at which point you may experience one or more of these symptoms:
Many people who have small stones will have them pass through the body on their own, while large stones tend to get stuck in the urinary tract. Pain is often unrelated to stone size. The smallest stones can cause the most discomfort, while large stones may sit quietly in the kidney causing only a dull ache.
Kidney Stone Diagnosis
Diagnosing a kidney stone requires a physical exam and a medical history to be taken by a physician. Typically a urinalysis (testing of a urine sample), an abdominal x-ray, a computerized tomography (CT) scan, or an ultrasound will be done to complete the diagnosis. According to the American Urological Association, the current gold standard for confirming kidney stones is a non-contrast CT of the abdomen and pelvis. Once a stone is detected, size and location are established and are key determinants in the best management and treatment options.
UCLA Urologist and kidney stone specialist Dr. Kymora Scotland talks about who forms kidney stones, why kidney stones cause pain, and what to expect when passing a stone. Watch >
For an appointment with a kidney stone specialist, please call 310-794-7700.