What are kidney stones?
Kidney stones are small pieces of hard, crystallized material that form in the kidney. Kidney stones are often made up of calcium, but can also contain uric acid or amino acids (proteins). Kidney stones, also called urolithiasis, are a common condition.
One or more kidney stones can form in one or both kidneys. Kidney stones begin as tiny specks and may gradually increase in size. A person with a small kidney stone may not have symptoms and may be unaware of the condition. In some cases, small stones in the urine may pass out of the kidney and move down the ureter, into the bladder, and out of the body without causing pain or serious problems.
Looking for a Doctor?
There are generally no symptoms of a large kidney stone that remains in the kidney. However, when a large kidney stone moves out of the kidney into the ureter toward the bladder, it causes severe flank, abdominal, and groin pain, called renal colic. Some have described renal colic as the most intense painful experience encountered in life. Other symptoms of a large kidney stone that has moved out of the kidney include blood in the urine, difficulty urinating, and nausea, with or without vomiting.
Kidney stones may be prevented in some cases by ensuring good hydration and with prescribed medication if you are in a high-risk population, such as those with a personal history of kidney stones. Once a stone has developed and causes symptoms, treatment may include hospitalization, pain medication, and certain procedures that remove or crush large stones so that the stone can move more easily out of the body. Small kidney stones may not require treatment.
Most kidney stones pass out of the body in the urine. On occasion, a kidney stone can get stuck in a ureter and result in potentially serious, even life-threatening complications, such as kidney infection and kidney damage. Seek immediate medical care (call 911) if you, or someone you are with, have symptoms of passing a kidney stone, such as severe flank or abdominal pain, not urinating, or bloody urine. Rapid diagnosis and treatment can help reduce the risk of complications.
Healthgrades Operating Company, Inc. All rights reserved. May not be reproduced
or reprinted without permission from Healthgrades Operating Company, Inc. Use
of this information is governed by the Healthgrades User Agreement.
- Kidney Stones. Medline Plus, a service of the National Library of Medicine National Institutes of Health. http://www.nlm.nih.gov/medlineplus/ency/article/000458.htm.
- Kidney Stones. National Kidney Foundation. http://www.kidney.org/atoz/content/kidneystones.cfm.
- Kidney Stones. PubMed Health, a service of the NLM from the NIH. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001493/.
- Kidney Stones in Adults. National Kidney and Urologic Diseases Information Clearinghouse. http://kidney.niddk.nih.gov/kudiseases/pubs/stonesadults/.
- Bope ET, Kellerman RD (Eds.) Conn’s Current Therapy. Philadelphia: Saunders, 2013.
- Domino FJ (Ed.) Five Minute Clinical Consult. Philadelphia: Lippincott Williams & Wilkins, 2013.