Health A to Z

Kidney stones

Are you at risk for kidney stones? Find out why certain factors - like not drinking enough water - can increase the odds.

A kidney stone can develop when chemicals in urine form crystals that stick together. They range in size from a grain of sand to a golf ball. One in ten Canadians will develop a kidney stone at some point in their life. Small stones can pass through the urinary system without difficulty; however, larger stones can cause severe pain while traveling through the ureter to the bladder.

Kidney stone causes Several factors make some people more prone to developing kidney stones, including drinking too little fluid, recurrent urinary tract infections, bed rest for several weeks, certain medications and consuming too much vitamin C or D. Men are more likely to develop kidney stones. They occur more often in middle-aged people and in hot climates.

Kidney stone symptoms Signs of a kidney stone include blood in the urine, severe pain that starts in the lower back or abdomen, and nausea and vomiting.

Kidney stone diagnosis/tests If you have symptoms, your doctor will conduct a medical examination, including asking questions about a family history of kidney illness, your diet and medications. She will do a urine test to check for blood in the urine and may order a blood test to see how your kidney is functioning, plus other tests including ultrasounds, CT scans or X-rays to check for kidney stones.

Kidney stone treatment Small stones may pass within hours or days without treatment. However, drinking plenty of fluids and taking pain medication may help the process. If a stone does not pass on its own, it may be removed using high-energy shock waves to break it up into smaller pieces. For stones larger than two centimeters, surgery may be necessary.

Kidney stone prevention To avoid more kidney stones, drink 12 glasses of liquids daily to help flush out the chemicals that form stones. Limit caffeine intake since it may make you lose fluid too rapidly. If you had a uric acid stone, your doctor may suggest that you eat less meat which breaks down to make uric acid. If you formed a calcium oxalate stone, you may need to avoid foods that contain high amounts of oxalate, such as chocolate and spinach. Your doctor may also prescribe you medications to prevent more kidney stones.

Outside resources
The Kidney Foundation of Canada