The lowdown on kidney stones

According to the Kidney Foundation of Canada, one out of 10 Canadians will have a kidney stone during his or her lifetime.

Kidney stones are crystals that develop when certain chemicals in your urine react in the kidneys and stick together. They can range in size from a grain of sand to a golf ball. Larger crystals can irritate the urinary tract or block the flow of urine altogether.

There are various causes of kidney stones and some people are more prone to developing the stones than others.


The Kidney Foundation of Canada gives the following causes:

• Frequent urinary tract infections.
• Blockage of the urinary tract.
• Not drinking enough fluid.
• Too much vitamin C or D.
• Too much calcium oxalate or uric acid in your diet.
• Certain prescriptions.
• Certain metabolic diseases.


The Kidney Foundation of Canada describes the symptoms as:

• Severe pain lasting minutes to hours, which starts in the lower back or abdomen and may radiate to the groin. The pain is usually broken up by periods of relief.
• Blood in the urine.
• Nausea and vomiting.
• An infection in the urinary tract may also cause cloudy or foul-smelling urine, burning while urinating and fever, chills and weakness.

Drinking lots of fluids and following a doctor-recommended diet may help smaller stones pass through the body by themselves. But medication or treatment may be required to dissolve larger stones, so the body can pass them.

Extra-corporal shock wave lithotripsy (ESWL) uses high-energy shock waves to break the stones into smaller crystals. It is a non-surgical treatment. If the stones are larger than two centimeters, then surgery may be required.

All stones should be analyzed by a laboratory to determine if they are formed from calcium oxalate or uric acid.

The Kidney Foundation of Canada says there are ways to prevent the formation of kidney stones. They recommend drinking a glass of water every hour throughout the day and after meals and exercise. Stones will reoccur in half of the people that get them. If you are prone to calcium oxalate stones then you shouldn’t consume large amount of dairy or use many antacids. You should also not take large doses of vitamin C. If you are more prone to the uric acid stones, you need to limit the amount of red meat in your diet.

Photo © Stephen Morris

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