Kidney stones (also called renal stones or urinary stones) are small, hard deposits that form in one or both kidneys; the stones are made up of minerals or other compounds found in urine. Kidney stones vary in size, shape, and color. To be cleared from the body (or "passed"), the stones need to travel through ducts that carry urine from the kidneys to the bladder (ureters) and be excreted. Depending on their size, kidney stones generally take days to weeks to pass out of the body.

Genetic changes can increase the risk of developing kidney stones, often acting in combination with a variety of environmental and lifestyle factors. Most genes involved in the condition are important for transmitting chemical signals from outside cells to inside cells or transporting materials in and out of cells. These processes help regulate the levels of various materials within cells, including the minerals and compounds that make up kidney stones. Changes in these genes can alter the levels of these materials in cells, leading to an imbalance of minerals and compounds in urine. As a result, the likelihood of stone formation increases.

In the United States, 9 percent of women and 19 percent of men develop kidney stones in their lifetime. Caucasians are more likely to develop kidney stones than African Americans.

The inheritance pattern of kidney stones is unclear. Overall, the risk of developing this condition is greater for individuals who have a close relative (such as a parent or sibling) with the condition as compared to the general public.

Published Date:updated Last, January

Published By: National Institutes of Health