Kidney stones
Renal calculi; Nephrolithiasis; Stones - kidney; Calcium oxalate - stones; Cystine - stones; Struvite - stones; Uric acid - stones; Urinary lithiasisA kidney stone is a solid mass made up of tiny crystals. One or more stones can be in the kidney or ureter at the same time.
Causes
Kidney stones are common. Some types run in families. They may occur at any age, including in premature infants.
There are different types of kidney stones. The cause depends on the type of stone.
Stones can form when urine contains too much of certain substances that form crystals. These crystals can develop into stones over weeks or months.
- Calcium stones are most common. They are most likely to occur in men between ages 20 to 30. Calcium can combine with other substances to form the stone.
- Oxalate is the most common of these substances. Oxalate is present in certain foods such as spinach. It is also found in vitamin C supplements. Diseases of the small intestine increase your risk for these stones.
Nephrolithiasis
Kidney stones result when urine becomes too concentrated and substances in the urine crystalize to form stones. Symptoms arise when the stones begin to move down the ureter causing intense pain. Kidney stones may form in the pelvis or calyces of the kidney or in the ureter.
Calcium stones can also form by combining with phosphate or carbonate.
Other types of stones include:
- Cystine stones can form in people who have cystinuria. This disorder runs in families. It affects both men and women.
Cystinuria
Cystinuria is a rare condition in which stones made from an amino acid called cysteine form in the kidney, ureter, and bladder. Cystine is formed wh...
Read Article Now Book Mark Article - Struvite stones are mostly found in men or women who have repeated urinary tract infections. These stones can grow very large and can block the kidney, ureter, or bladder.
Urinary tract infections
If you swallow a foreign object, it can get stuck in the gastrointestinal (GI) tract from the esophagus (swallowing tube) to the colon (large intesti...
Read Article Now Book Mark Article - Uric acid stones are more common in men than in women. They can occur with gout or after receiving chemotherapy for some types of cancer.
- Other substances, such as certain medicines, also can form stones.
Cystinuria
Cystinuria is a disorder characterized by cystine stones in the kidney, ureter, and bladder. A genetic abnormality results in abnormal transport of amino acids in the kidney. The high levels of the amino acid cystine in the urine lead to stone formation.
The biggest risk factor for kidney stones is not drinking enough fluids. Kidney stones are more likely to occur if you make less than 1 liter (32 ounces) of urine a day.
Symptoms
You may not have symptoms until the stone moves down the tube (ureters) through which urine empties into your bladder. When this happens, the stone can block the flow of urine out of the kidneys, causing pain.
The main symptom is severe pain that starts and stops suddenly:
- Pain may be felt in the belly area or side of the back.
- Pain may move to the groin area (groin pain), testicles (testicle pain) in men, and labia (vaginal pain) in women.
Groin pain
Groin pain refers to discomfort in the area where the abdomen ends and the legs begin. This article focuses on groin pain in men. The terms "groin"...
Read Article Now Book Mark ArticleTesticle pain
Testicle pain is discomfort in one or both testicles. The pain can spread into the lower abdomen.
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Kidney pain
A kidney stone is a solid piece of material that forms in a kidney. Kidney stones may be the size of sand or gravel, as large as a pearl, or even larger. A stone can block the flow of urine and cause great pain.
Other symptoms can include:
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Abnormal urine color
Abnormal urine color
The usual color of urine is straw-yellow. Abnormally-colored urine may be cloudy, dark, or blood-colored.
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Blood in the urine
Blood in the urine
Blood in your urine is called hematuria. The amount may be very small and only detected with urine tests or under a microscope. In other cases, the...
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Chills
Chills
Chills refers to feeling cold after being in a cold environment. The word can also refer to an episode of shivering along with paleness and feeling ...
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Fever
Fever
Fever is the temporary increase in the body's temperature in response to a disease or illness. A child has a fever when the temperature is at or abov...
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Nausea and vomiting
Nausea and vomiting
Nausea is feeling an urge to vomit. It is often called "being sick to your stomach. "Vomiting or throwing-up forces the contents of the stomach up t...
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Exams and Tests
Your health care provider will perform a physical exam. The belly area (abdomen) or back might feel sore.
Tests that may be done include:
- Blood tests to check calcium, phosphorus, uric acid, and electrolyte levels
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Kidney function tests
Kidney function tests
Kidney function tests are common lab tests used to evaluate how well the kidneys are working. Such tests include:BUN (Blood urea nitrogen) Creatinin...
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Urinalysis to check for crystals and red blood cells in urine
Urinalysis
Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds th...
Read Article Now Book Mark ArticleRed blood cells in urine
The RBC urine test measures the number of red blood cells in a urine sample.
Read Article Now Book Mark Article - Examination of the stone to determine the type
Stones or a blockage can be seen on:
-
Abdominal CT scan
Abdominal CT scan
An abdominal CT scan is an imaging method. This test uses x-rays to create cross-sectional pictures of the belly area. CT stands for computed tomog...
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Abdominal x-rays
Abdominal x-rays
An abdominal x-ray is an imaging test to look at organs and structures in the abdomen. Organs include the liver, spleen, stomach, and intestines. Wh...
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Kidney ultrasound
Kidney ultrasound
Abdominal ultrasound is a type of imaging test. It is used to look at organs in the abdomen, including the liver, gallbladder, spleen, pancreas, and...
Read Article Now Book Mark Article - Retrograde pyelogram
Treatment
Treatment depends on the type of stone and the severity of your symptoms.
Kidney stones that are small most often pass through your system on their own.
- Your urine should be strained so the stone can be saved and tested.
- Drink at least 6 to 8 glasses of water per day to produce a large amount of urine. This will help the stone pass.
Stone pass
A kidney stone is a small solid mass made up of tiny crystals. Your health care provider may ask you to take self-care steps to treat kidney stones ...
Read Article Now Book Mark Article - Pain can be very bad. Over-the-counter pain medicines (for example, ibuprofen and naproxen), either alone or along with narcotics, can be very effective.
Some people with severe pain from kidney stones need to stay in the hospital. You may need to get fluids through an IV into your vein.
For some types of stones, your provider may prescribe medicine to prevent stones from forming or help stones pass through your urinary system. These medicines can include:
- Allopurinol (for calcium oxalate or some uric acid stones)
Uric acid
Uric acid is a chemical created when the body breaks down substances called purines. Purines are normally produced in the body and are also found in...
Read Article Now Book Mark Article - Antibiotics (for struvite stones)
- Phosphate solutions
- Potassium citrate
- Water pills (thiazide diuretics)
- Tamsulosin to relax the ureter and help the stone pass
Surgery is often needed if:
- The stone is too large to pass on its own.
- The stone is growing.
- The stone is blocking urine flow and causing an infection or kidney damage.
- The pain cannot be controlled.
Today, most treatments are much less invasive than in the past.
-
Lithotripsy is used to remove stones slightly smaller than one half an inch (1.25 centimeters) that are located in the kidney or ureter. It uses sound or shock waves to break up stones into tiny fragments. Then, the stone fragments leave the body in the urine. It is also called extracorporeal shock-wave lithotripsy or ESWL.
Lithotripsy
Lithotripsy is a procedure that uses shock waves to break up stones in the kidney and parts of the ureter (tube that carries urine from your kidneys ...
Read Article Now Book Mark Article - Procedures performed by passing a special instrument through a small surgical cut in your skin on your back and into your kidney or ureters are used for large stones, or when the kidneys or surrounding areas are incorrectly formed. The stone is removed with a tube (endoscope).
Passing a special instrument
Percutaneous (through the skin) urinary procedures help drain urine from your kidney and get rid of kidney stones.
Read Article Now Book Mark Article - Ureteroscopy may be used for stones in the lower urinary tract. A laser is used to break up the stone.
- Rarely, open surgery (nephrolithotomy) may be needed if other methods do not work or are not possible.
Lithotripsy procedure
Extracorporeal shock wave lithotripsy (ESWL) is a procedure used to shatter simple stones in the kidney or upper urinary tract. Ultrasonic waves are passed through the body until they strike the dense stones. Pulses of sonic waves pulverize the stones, which are then more easily passed through the ureter and out of the body in the urine.
Talk to your provider about what treatment options may work for you.
Talk to your provider
A kidney stone is a solid piece of material that forms in your kidney. The kidney stone may get stuck in your ureter (the tube that carries urine fr...
Read Article Now Book Mark ArticleYou will need to take self-care steps. Which steps you take depend on the type of stone you have, but they may include:
Self-care steps.
A kidney stone is a small solid mass made up of tiny crystals. Your health care provider may ask you to take self-care steps to treat kidney stones ...
Read Article Now Book Mark Article- Drinking extra water and other liquids
- Eating more of some foods and cutting back on other foods
- Taking medicines to help prevent stones
- Taking medicines to help you pass a stone (anti-inflammatory drugs, alpha-blockers)
Outlook (Prognosis)
Kidney stones are painful, but most of the time can be removed from the body without causing lasting damage.
Kidney stones often come back. This occurs more often if the cause is not found and treated.
You are at risk for:
- Urinary tract infection (UTI)
- Kidney damage or scarring if treatment is delayed for too long
Possible Complications
Complications of kidney stones may include the obstruction of the ureter (acute unilateral obstructive uropathy).
When to Contact a Medical Professional
Contact your provider if you have symptoms of a kidney stone:
- Severe pain in your back or side that will not go away
- Blood in your urine
-
Fever and chills
Fever
Fever is the temporary increase in the body's temperature in response to a disease or illness. A child has a fever when the temperature is at or abov...
Read Article Now Book Mark Article -
Vomiting
Vomiting
Nausea is feeling an urge to vomit. It is often called "being sick to your stomach. "Vomiting or throwing-up forces the contents of the stomach up t...
Read Article Now Book Mark Article - Urine that smells bad or looks cloudy
- A burning feeling when you urinate
If you have been diagnosed with blockage from a stone, passage must be confirmed either by capture in a strainer during urination or by follow-up x-ray. Being pain free does not confirm that the stone has passed.
Prevention
If you have a history of stones:
- Drink plenty of fluids (6 to 8 glasses of water per day) to produce enough urine.
- You may need to take medicine or make changes to your diet for some types of stones.
- Your provider may want to do blood and urine tests to help determine the proper prevention steps.
References
American Urological Association website. Medical management of kidney stones (2019). www.auanet.org/guidelines-and-quality/guidelines/kidney-stones-medical-mangement-guideline. Updated 2019. Accessed January 31, 2024.
American Urological Association website. Surgical management of stones: AUA/Endourology Society guideline (2016). www.auanet.org/guidelines-and-quality/guidelines/kidney-stones-surgical-management-guideline. Updated 2016. Accessed January 31, 2024.
Bushinsky DA. Nephrolithiasis. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 111.
Miller NL, Borofsky MS. Evaluation and medical management of urinary lithiasis. In: Partin AW, Dmochowski RR, Kavoussi LR, Peters CA, eds. Campbell-Walsh-Wein Urology. 12th ed. Philadelphia, PA: Elsevier; 2021:chap 92.
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Kidney stones
Animation
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Kidney stones
Animation
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Kidney anatomy - illustration
The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and the stimulation of red blood cell production.
Kidney anatomy
illustration
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Kidney - blood and urine flow - illustration
This is the typical appearance of the blood vessels (vasculature) and urine flow pattern in the kidney. The blood vessels are shown in red and the urine flow pattern in yellow.
Kidney - blood and urine flow
illustration
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Nephrolithiasis - illustration
Kidney stones result when urine becomes too concentrated and substances in the urine crystalize to form stones. Symptoms arise when the stones begin to move down the ureter causing intense pain. Kidney stones may form in the pelvis or calyces of the kidney or in the ureter.
Nephrolithiasis
illustration
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Lithotripsy procedure - illustration
Extracorporeal shock wave lithotripsy (ESWL) is a procedure used to shatter simple stones in the kidney or upper urinary tract. Ultrasonic waves are passed through the body until they strike the dense stones. Pulses of sonic waves pulverize the stones, which are then more easily passed through the ureter and out of the body in the urine.
Lithotripsy procedure
illustration
-
Cystinuria - illustration
Cystinuria is a disorder characterized by cystine stones in the kidney, ureter, and bladder. A genetic abnormality results in abnormal transport of amino acids in the kidney. The high levels of the amino acid cystine in the urine lead to stone formation.
Cystinuria
illustration
-
Kidney pain - illustration
A kidney stone is a solid piece of material that forms in a kidney. Kidney stones may be the size of sand or gravel, as large as a pearl, or even larger. A stone can block the flow of urine and cause great pain.
Kidney pain
illustration
-
Kidney anatomy - illustration
The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and the stimulation of red blood cell production.
Kidney anatomy
illustration
-
Kidney - blood and urine flow - illustration
This is the typical appearance of the blood vessels (vasculature) and urine flow pattern in the kidney. The blood vessels are shown in red and the urine flow pattern in yellow.
Kidney - blood and urine flow
illustration
-
Nephrolithiasis - illustration
Kidney stones result when urine becomes too concentrated and substances in the urine crystalize to form stones. Symptoms arise when the stones begin to move down the ureter causing intense pain. Kidney stones may form in the pelvis or calyces of the kidney or in the ureter.
Nephrolithiasis
illustration
-
Lithotripsy procedure - illustration
Extracorporeal shock wave lithotripsy (ESWL) is a procedure used to shatter simple stones in the kidney or upper urinary tract. Ultrasonic waves are passed through the body until they strike the dense stones. Pulses of sonic waves pulverize the stones, which are then more easily passed through the ureter and out of the body in the urine.
Lithotripsy procedure
illustration
-
Cystinuria - illustration
Cystinuria is a disorder characterized by cystine stones in the kidney, ureter, and bladder. A genetic abnormality results in abnormal transport of amino acids in the kidney. The high levels of the amino acid cystine in the urine lead to stone formation.
Cystinuria
illustration
-
Kidney pain - illustration
A kidney stone is a solid piece of material that forms in a kidney. Kidney stones may be the size of sand or gravel, as large as a pearl, or even larger. A stone can block the flow of urine and cause great pain.
Kidney pain
illustration
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Kidney stones
(Alt. Medicine)
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Kidney stones - InDepth
(In-Depth)
Review Date: 1/1/2022
Reviewed By: Kelly L. Stratton, MD, FACS, Associate Professor, Department of Urology, University of Oklahoma Health Sciences Center, Oklahoma City, OK. Internal review and update on 01/31/2024 by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.