A kidney stone is a solid mass made up of tiny crystals. One or more stones can be in the kidney or ureter at the same time.

There are different types of kidney stones. The exact cause depends on the type of stone. Stones can form when urine contains too much of certain substances. These substances can create small crystals that become stones. The stones take weeks or months to form.

You may not have symptoms until the stones move down the tubes (ureters) through which urine empties into your bladder. When this happens, the stones can block the flow of urine out of the kidneys. The main symptom is severe pain that starts suddenly and may go away suddenly. Pain may be felt in the belly area or side of the back. Pain may move to groin area (groin pain) or testicles (testicle pain).

Today, most treatments are much less invasive than in the past. Extracorporeal shock-wave lithotripsy is used to fragment stones that are located in the kidney or ureter. It uses shock waves to break up stones. Then, the stones leave the body in the urine. Learn more about lithotripsy.

Call your health care provider if you have symptoms of a kidney stone. Also call if symptoms return, urination becomes painful, urine output decreases, or other new symptoms develop. Visit our Physician Directory to find a Keystone affiliated physician.