What is kidney stones?

Kidney Stones

Kidney stones

Kidney stones are small stones made of minerals in the urine that stick together. They can cause severe pain as they travel through the ureters (tubes that connect the kidneys and the bladder) to exit the body when you urinate.

Your doctor may give you medicine to ease the pain until you pass the stone. If the stone is too large or gets stuck, other treatment is needed.

What happens when you have kidney stones?

Small stones leave the kidney as the urine carries them out of the body. If stones stay in the kidney, they may grow larger. They can become stuck in the ureters, the tubes that carry urine from the kidney to the bladder. This causes pain. Some larger stones need medical treatment.

Kidney Stone in Ureter

A kidney stone in the ureter

Kidney stones are made of salts and minerals in the urine that stick together to form small "pebbles." They are usually painless while they remain in the kidney. But they can cause severe pain when small pieces leave the kidney and travel through the narrow tubes (ureters) to the bladder.

Symptoms of a kidney stone include severe pain in the flank, which is felt just below the rib cage and above the waist, usually on only one side of the back. The pain may spread to the lower abdomen, groin, and genital area. Other symptoms include blood in the urine (hematuria), painful or frequent urination (dysuria), and nausea and vomiting.

What are the types of kidney stones?

The four main types of kidney stones are:

Calcium stones.

Most kidney stones are made of calcium compounds. Conditions that cause high calcium levels in the body, such as hyperparathyroidism, increase the risk of calcium stones.

Uric acid stones.

Some kidney stones are made of uric acid, a waste product in urine. You're more likely to have uric acid stones if you have:

  • Low urine output.
  • A diet high in animal protein, such as red meat.
  • An increase in how much alcohol you drink.
  • Gout.
  • Inflammatory bowel disease.
Struvite stones.

Some kidney stones are struvite stones. These can be serious, because they are often large stones and may occur with an infection.

Cystine stones.

Stones made of a chemical called cystine are less common. They're more likely to occur in people who have a condition that results in too much cystine in the urine (cystinuria).

How are kidney stones treated?

For most stones, your doctor will recommend home care, such as pain medicine and drinking plenty of water. You may get a medicine to help the stone pass. If it is too large to pass, you may need other treatment, such as one that uses shock waves to break the stone into small pieces.

How can you help prevent kidney stones?

You can help prevent kidney stones by drinking plenty of water. Try to drink about 8 to 10 glasses a day. Eating less of certain foods may also help. Your doctor may give you medicine that helps prevent stones from forming.

How are kidney stones diagnosed?

Kidney stones may be diagnosed when you see your doctor or go to an emergency room with pain in your belly or side. Your doctor will ask about your symptoms and examine you.

Your doctor may do tests to help diagnose kidney stones and see where they're located. Tests include:

  • A noncontrast spiral CT scan. This is a special type of CT scan that moves in a circle.
  • An ultrasound exam (ultrasonogram). This uses reflected sound waves to examine your urinary tract.
  • An intravenous pyelogram (IVP). This is an X-ray test that shows pictures of the urinary tract and kidney stones.
  • A retrograde pyelogram. This uses a dye to check whether a kidney stone or something else is blocking your urinary tract.
  • Urinalysis and urine cultures. These test your urine.
  • An abdominal X-ray (KUB). This creates a picture of the kidneys, the bladder, and the tubes that connect the kidneys to the bladder (ureters).

How can you care for yourself when you have kidney stones?

Drinking more fluids and taking pain medicine are often the only things you need to do when you pass a kidney stone. Drink enough water. Over-the-counter pain medicine, like aspirin and ibuprofen, may help relieve your pain.

What increases your risk for kidney stones?

Several things can affect your risk for getting kidney stones. These include:

  • How much fluid you drink. The most common cause of kidney stones is not drinking enough water.
  • Your diet. Diets high in protein and sodium increase your risk for kidney stones. So do oxalate-rich foods, such as dark green vegetables. If you think that your diet may be a problem, a dietitian can help.
  • Being overweight. This can cause both insulin resistance and increased calcium in the urine, which can increase your risk for kidney stones.
  • Medicine. Some medicines can cause kidney stones to form.

Your age, gender, and whether you have a family history of kidney stones can also affect your risk. But these things are out of your control.

What causes kidney stones?

Kidney stones form when a change occurs in the normal balance of water, salts, minerals, and other things in urine. The most common cause is not drinking enough water. Some people are more likely to get kidney stones because of a medical condition, such as gout. They may also be an inherited disease.

What are kidney stones?

Kidney stones are small "pebbles" that form in your kidneys. They're made of salts and minerals in the urine. They may stay in your kidneys or exit your body through the urinary tract. A stone traveling through a ureter—a tube that connects the kidney to the bladder—usually causes pain and other symptoms.

Kidney stone: When to call

Call your doctor now or seek immediate medical care if:

  • You cannot keep down fluids.
  • Your pain gets worse.
  • You have a fever or chills.
  • You have new or worse pain in your back just below your rib cage (the flank area).
  • You have new or more blood in your urine.

Watch closely for changes in your health, and be sure to contact your doctor if:

  • You do not get better as expected.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.

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