What is Hypercalciuria?

Hypercalciuria is the term used when a person has high levels of calcium in his or her urine. This condition may have numerous possible causes and can lead to a variety of side effects. It's usually discovered only after symptoms of these side effects occur and urine samples are tested to determine a cause. Treatment can vary, but often includes dietary changes and medication.

Many cases of hypercalciuria are thought to occur due to the intestines absorbing more calcium than normal. This can happen, for example, if a person ingests too much calcium over a period of time, such as by taking calcium-based antacids, or drinking or eating large quantities of calcium-containing foods, such as milk and cheese. It can also happen if a person gets too much vitamin D, such as through dietary supplements, which can increase the amount of calcium the intestines absorb even if calcium intake is normal.

Some medical conditions can also cause hypercalciuria, including Dent’s disease and hyperparathyroidism. Dent’s disease is a rare genetic disorder that changes the way the kidneys work, causing them to excrete too much calcium. Hyperparathyroidism is an overproduction of parathyroid hormones, often caused by swelling of the hyperparathyroid glands, which can cause the bones in the body to release calcium stores. This can then lead to hypercalciuria as the body tries to eliminate the extra calcium circulating in the blood via the urine.

When a person has hypercalciuria, he or she may experience side effects such as kidney stones or, in the case of hyperparathyroidism, osteoporosis. These conditions can be caused by other problems as well, so health-care providers typically run tests to determine the cause. One such test may include a 24-hour urine calcium test, which involves collecting all of the urine excreted over a 24-hour period and then assessing the total amount of calcium contained within it. If the calcium is over a certain level, often 250-300 milligrams, a person is typically diagnosed with hypercalciuria.

One of the primary treatments for hypercalciuria is dietary management. Many health-care providers recommend people with the condition eat less salt and meat, drink less caffeine and alcohol, drink more water, eat more fiber, and get moderate amounts of calcium. If over consumption of calcium and/or vitamin D is suspected, health-care providers will often recommend cutting back on the foods or supplements contributing to this.

In some cases, medications may also be needed to help treat hypercalciuria or the underlying cause. Some of the most common medications fall into a class known as diuretics, which work on the kidneys and help reduce the amount of calcium being excreted. Other medications may include orthophosphates, which help eliminate excess levels of vitamin D in the body, and bisphosphonates, which can help direct calcium circulating in the body to be stored to the bones, thereby keeping it out of the urine.