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Stones in the Urinary Tract (Kidney Stones)


The Manual's Editorial Staff

Reviewed/Revised Feb 2023
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What is the urinary tract?

Your urinary tract includes:

  • Kidneys, two bean-shaped organs that make urine

  • Ureters, the tubes that drain urine from each kidney to your bladder

  • Bladder, a hollow organ that holds urine until you urinate (pee)

  • Urethra, a tube attached to the bladder that allows urine to flow out of your body

The Urinary Tract

The Urinary Tract

What are kidney stones?

Kidney stones are hard little pebbles that form in your kidneys. The stones can be too tiny to see or more than an inch in size. Sometimes the stones stay in your kidneys and don't cause any problems. Sometimes the stones leave your kidneys and travel down your urinary tract. If a stone leaves your kidney, it will either get stuck somewhere in your urinary tract or you will pee it out.

When stones travel in the urinary tract, they can cause pain and bleeding. If they get stuck, they also can cause an infection or block the flow of urine. If the flow of urine is blocked for a long time, the kidney can swell up enough to be damaged.

As stones travel through your urinary tract, they may be called different names based on where they are located:

  • A stone in one of your ureters may be called a ureteral stone

  • A stone in your bladder may be called a bladder stone

What causes kidney stones?

There are many different kinds of stones with many different causes. You're more likely to have stones if you:

  • Have too much calcium (a mineral) or other substances in your urine

  • Have certain medical problems, including certain cancers

  • Have people in your family who've had kidney stones

  • Eat certain foods

  • Are middle-aged or older

  • Are male

What are the symptoms of kidney stones?

Tiny stones may not cause symptoms.

Stones in your bladder may cause pain in the lower abdomen (belly area).

Stones in a kidney or ureter may cause back pain, usually in the area between your ribs and hip. The pain can also be across your belly and down between your legs. The pain is very severe and comes and goes.

Other symptoms include:

  • Feeling sick to your stomach and vomiting (throwing up)

  • Having reddish-brown or bloody urine

  • Feeling like you need to pee more often

  • Having burning or pain when you pee

If the stone causes an infection, your urine may be cloudy or smelly and you may have a fever.

How can doctors tell if I have a kidney stone?

How do doctors treat kidney stones?

Small stones that aren't causing a blockage or an infection don't need to be treated. The stone will often pass on its own. You may need medicine for pain.

Larger stones usually don't pass on their own. You will need medicine for pain. If the stone doesn't pass, doctors usually need to remove it. To remove your stone, doctors might:

  • Use powerful sound waves to break up the stone into tiny pieces (a procedure called lithotripsy)

  • Use a scope to remove the stone

When using a scope to remove a stone, doctors might:

  • Put the scope up your urethra

  • Put the scope into your kidney through a small cut (incision) in your back

Once the scope is in, doctors can pull the stone out with the scope. Or they may need to break it up with a laser or other methods such as shock wave lithotripsy. A stone that has been broken into small pieces will come out when you pee.

Doctors usually need to see what the stone is made of after it's broken into pieces. They'll have you pee through a strainer to collect the stone pieces. You'll give the pieces to your doctor for testing.

How can I prevent more kidney stones?

That depends on what the stone you had was made of (calcium or another substance). Some things that may help prevent stones from forming:

  • Avoiding certain foods

  • Drinking more water

  • Taking certain medicines

What foods to avoid depends on what type of stone you had. Your doctor will talk to you about that.

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