A to Z: Kidney Stones
May also be called: Calculi; Nephrolithiasis
Kidney stones are small, solid masses that form in the urinary tract. Kidney stones are caused by the build-up of substances normally found in urine (pee), like salts and calcium.
More to Know
When substances normally found in urine become extra concentrated, they can form crystals in the kidneys. These crystals can build up to become stones over a few weeks or months.
Small kidney stones can pass through the urinary tract and out of the body with little or no pain, but larger stones can be quite painful, block the flow of urine, and cause blood in the urine and other symptoms. In some cases, kidney stones can lead to problems with the kidneys and urinary tract. Most kidney stones, however, cause no permanent damage.
Keep in Mind
Kidney stones are fairly common. There are different types of kidney stones with many different causes. Treatment depends on the type and size of the stones.
All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.
NKF seeks to prevent kidney and urinary tract diseases, improve the health and well-being of individuals and families affected by these diseases, and increase the availability of all organs for transplantation.
This group conducts and supports research on many serious diseases affecting public health.
This site, operated by the American Academy of Family Physicians (AAFP), provides information on family physicians and health care, a directory of family physicians, and resources on health conditions.
The AAKP serves kidney patients and their families by helping them cope with the emotional, physical, and social impact of kidney failure.
The AAP is committed to the health and well-being of infants, adolescents, and young adults. The website offers news articles and tips on health for families.
The Nephron Information Center offers information about how the kidneys work, transplants, and links to other sites.