Kidney Stone Analysis
How It Is Done
The kidney stone you take to the lab
will be cleaned of any blood or tissue and then looked at to find what
chemicals it is made of.
How It Feels
The most common way a kidney stone is
collected for this test is by passing it in urine. Passing a stone may be
painless or it may be very painful. The pain can begin suddenly and may come
and go. A sand-sized stone may pass with little pain. A larger stone may cause
a lot of pain in the lower back, groin, or genitals as it moves down the
ureters or the urethra.
A small stone may pass without medical
treatment. A large stone may need surgery or another type of procedure to get
There is no chance for problems with kidney stone
analysis. But a kidney stone can:
- Have bacteria that can cause a
urinary tract infection (UTI).
- Damage the kidney, especially if the stone is a staghorn
- Block the urinary tract. This can happen while the stone is
passing through the tract.
Kidney stone analysis is a test done on a
kidney stone to see what chemicals are in it.
Knowing the type of kidney stone helps guide the best treatment choice.
Your doctor will talk with you about treatment and prevention measures.
- About 80% of kidney stones are made of calcium oxalate, calcium
phosphate, or a combination of both.1
- About 10% to 15% of kidney stones are made of magnesium ammonium
- About 5% to 10% of kidney stones are made of uric acid.1
- Less than 1% of kidney stones are made of a chemical called
What Affects the Test
Putting tape on a kidney stone to
keep it safe on the way to the lab may cause a problem with the test
What To Think About
- About 80% of kidney stones in the ureters can be seen on an
computed tomography (CT) scan of the
ureters and kidneys (also called a CT urogram) is the
most common way to find kidney stones. To learn more, see the topic
CT Scan of the Body.
Ultrasound may also be used to find kidney stones. To learn more, see the topic
- Another test that can be done to find a kidney stone is
intravenous pyelogram (IVP). During IVP, a dye is put
into a vein in your arm. As the dye moves to the kidneys, X-rays are taken to
watch the movement of the dye and see where a stone may be. To learn more, see the topic
Intravenous Pyelogram (IVP).
- Most kidney stones have calcium in them. A low-calcium diet does
not often prevent stones from forming. To learn more about lowering your
chance for a kidney stone, see the topic
- Knowing the type of kidney stone helps guide the best treatment