What are Kidney Stones?

Kidney stones occur when minerals filtered from the blood combine to form hard deposits in the ducts that drain the kidney. It is uncommon before age 20 and peaks at around age 50. Those who suffer from kidney stones in the U.S. are more often than not Caucasian men who live in the southeastern region, or those states with warmer temperatures. Men are twice as likely as women to have kidney stones at some point during their lives, and Caucasians more than any other race.

Most kidney stones are made of calcium. Less common are uric acid stones, infection (struvite) stones, and cystine stones. Some people form stones very early in life and may have frequent episodes of pain when they pass the stones. Others may have only one or two stone episodes starting much later in life.