How to Diagnose a Kidney Stone

A kidney stone is a hard deposit of salt from an acid or mineral. These substances are normal components of urine, but are normally too dilute to form a solid. However, they may form kidney stones when the urine becomes sufficiently concentrated. Most kidney stones are detected only when you have an unrelated examination or when they're large enough to cause painful urination.

Things You'll Need

• Blood sample
• Urine sample
• CT image
• Ultrasound image
• Intravenous pyelography image

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Instructions

• 1

  Observe pain during urination. A kidney stone that is sufficiently large can cause intense pain as it passes from the kidney through the ureter during urination. This pain typically originates on the side just below the ribs and radiates down to the groin.

• 2

  Perform laboratory tests. Blood tests for high levels of calcium and uric acid can determine whether these compounds may be responsible for the formation of kidney stones. You might be asked to provide urine samples over a 24-hour period see whether the composition of your urine makes kidney stones a likely possibility.

• 3

  Run a Computed Tomography (CT) scan. This imaging method is the most definitive way to diagnose kidney stones. It's noninvasive and can detect kidney stones regardless of their composition. Due to the expense, however, a CT scan is normally run only when a kidney stone is already strongly suspected.

• 4

  Take an ultrasound image. This method is safer than a CT scan and less expensive, but it may also fail to detect small kidney stones. It's especially hard to detect a small kidney stone if it's already in the bladder or ureter.

• 5

  Perform an intravenous pyelography. This test involves injecting a contrast dye into your arm and taking a series of x-rays as the dye moves through your body. This is an older test but it can still be useful in visualizing the blockage of urine a kidney stone causes.