A kidney stone, also known as renal calculi or nephrolithiasis, is a hardened mass of mineral and acid salts that separates from the urine and travels through the urinary tract. The urine normally dilutes and dissolves these substances, but when the composition of urine is unbalanced, crystallized stones can form. Kidney stones are a common but painful urinary tract disorder that affects over three million people in the United States each year.
There are several different types of kidney stones made up of different components found in the urine. Some of the most common stones are composed of calcium, struvite, uric acid, or cystine.
Causes of Kidney Stones
While the causes for all kidney stones are not known, possible causes may be:
- Family history
- Chronic diarrhea
- Crohn's disease
- A high level of calcium in the urine
Symptoms of Kidney Stones
Despite their composition, most kidney stones cause terrible pain as they move through the urinary tract and into the ureter. Common symptoms may include:
- Pain in the lower side and back
- Pain radiating to the abdomen and groin
- Bloody or cloudy urine
- Frequent and painful urination
Diagnosis of Kidney Stones
Kidney stones can be identified on X-rays even when they do not cause any symptoms. The following tests may also be used to diagnose this condition:
- Blood tests
- Urine tests
- Intravenous pyelogram, or IVP
- CT scan
Treatment of Kidney Stones
Treatment is not usually necessary for small kidney stones as most stones typically pass on their own after drinking plenty of water. Pain medication may be prescribed to relieve symptoms. Larger stones that cannot pass on their own or that block the urinary tract may require more aggressive methods such as shock wave therapy or ureteroscopy, a procedure used to find the location of the stone and then break it up.
Prevention of Kidney Stones
While all kidney stones cannot be avoided, certain behavioral changes such as drinking plenty of fluids and a change in diet to avoid troublesome foods, may prevent possible occurrences. People who have had previous kidney stones are more likely to have a recurrence, but implementing these changes may help to reduce future risk.
- National Institutes of Health
- Centers for Disease Control and Prevention
- Eunice Kennedy Shriver National Institute of Child Health and Human Development
- U.S. Department of Health & Human Services
- U.S. National Library of Medicine