Kidneys play an important role in keeping your body healthy. They remove waste from the body through urine, help make red blood cells, and regulate your blood pressure. The kidneys are two bean-shaped organs about the size of a fist, located under the rib cage on each side of the spine.
For your body to function properly, it must balance the minerals within the body and keep many of the substances in the blood and other body fluids at the right level. When the kidneys are working properly, extra water and minerals such as sodium and potassium, leave your body in the urine.
Sometimes when they aren’t working properly, you can develop kidney stones. Both men and women can develop kidney stones, but men are more prone to developing them. According to the Kidney Foundation of Canada, about 12% of men and 6% of women will have a kidney stone at some point in their life.
In men, the first kidney stone is usually diagnosed between the ages of 40 and 60. For women, the age range is younger – between the ages of 25 to 30. Kidney stones also have a recurrence rate; it’s estimated that their likeliness to return is 15% in the first year and 50% in the following 10 years.
When urine has high levels of minerals and salts and low levels of liquid, it can crystalize to form a hard deposit known as a kidney stone (also called renal calculi, nephrolithiasis, or urolithiasis). Some kidney stones are the size of a grain of sand and may pass through the body in the urine without you knowing it. However, larger stones travelling from the kidney through the ureter to the bladder can cause severe pain.
Most kidney stones are caused by low urine volume and dietary factors, and are linked to family history. According to the Kidney Foundation of Canada, you are two and half times more likely to develop a kidney stone if one of your relatives has had one. This could be due to both genetic and environmental factors, such as having a similar diet or drinking patterns in families.
Low urine volumes from not drinking enough fluids or dehydration can cause your urine to be more concentrated. When it is more concentrated there is less fluid to keep salts dissolved.
Drinking more fluids will help to dilute the salts in your urine and reduce the risk of stones forming. Diet can also impact your chance of forming a kidney stone. Alberta Health Services has the following dietary recommendations to help avoid kidney stones:
Other risk factors of kidney stones include excess body weight, certain supplements and medications, and some medical conditions.
Small kidney stones frequently don’t cause damage and will pass through the urinary tract unnoticed. Larger stones can be quite painful. These hard mineral deposits start to hurt when they cause irritation or a blockage. This can make urinating difficult or increase pressure on the kidneys, often resulting in a sharp pain in the lower back.
Symptoms could be one or more of the following:
For kidney symptoms, such as pain, frequent urination, uncomfortable urination, etc., it’s important to speak with your health care practitioner. Your doctor will likely order a number of tests to investigate the cause for these symptoms. These tests often include blood or urine tests, and possibly medical imaging.
If needed, the following medical imaging exams could be ordered to investigate kidney stones:
For more information about these exams and how to prepare, please visit our services page.