What Is Urinary Calculi?

Urinary calculi, or stones, are masses that form within the urinary tract. Most calculi pass through the urinary drainage system and out of the body without problems, but calculi that block drainage tubes can cause significant pain and other symptoms.

Identification

• Urinary calculi can develop in the kidney, the bladder or the ureters (the tubes between the kidney and bladder).

Features

• The Merck Manual says that 80 percent of urinary calculi are comprised of calcium, while the rest are made from substances such as cystine (an amino acid) or struvite (a phosphate mineral). Some urinary calculi are formed from uric acid, a substance formed when our bodies break down purine from our food.

Effects

• When urinary calculi block part of the drainage system, the body responds with spasms, or colic, of the involved structures. Stones in the ureters or kidneys can cause back pain, or flank pain that radiates down to the pelvis or genital area. Urinary calculi can also cause fever, chills, nausea, vomiting and a feeling of urinary urgency.

Prevention/Solution

• If you're prone to urinary calculi, you should drink plenty of water (8 to 10 glasses a day) to reduce your risk of stone formation.

Treatment

• Medications can help the body pass some urinary stones, but many urinary calculi respond best to sound waves (lithotripsy) or surgical procedures.