0121_Gout_Kidney_Stones
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Gout and kidney stones can both be incredibly painful conditions. They are both related to kidney function. But how are they related to each other? Can gout cause kidney stones, or can having kidney stones predispose you to gout?

Here’s what you need to know if you’re concerned about either of these conditions and how they’re connected.

Gout develops when the body has high levels of uric acid, a normal waste product. This is known as hyperuricemia. Uric acid is normally excreted through the body via the kidneys, but in some people, levels can remain high and uric acid can start to accumulate and crystallize in various joints. A gout attack can feel like a burning pain or a tingling sensation, depending on where the attack occurs. Regardless, the pain is, “off the charts, completely intolerable,” as CreakyJoints member Louise B. previously told us.

For people whose kidneys don’t filter waste well, the excess uric acid can crystalize in the kidney and form a type of kidney stone known as a uric acid stone.

However, uric acid kidney stones are just one type of kidney stone. Other types of kidney stones are unrelated to gout and can develop from a build-up of other substances, such as calcium, struvite, or cystine — chemicals your body gets rid of through the kidneys. Kidney stones can feel like a sharp, cramping pain in the back and side, according to the Urology Care Foundation.

Trying to pass these stones can cause scarring and damage to the kidney, and may lead to long-term kidney disease, according to the American Kidney Fund.

Learn more about the link between gout and kidney stones and how to better manage gout to reduce your risk.

How Does Gout Cause Kidney Stones?

People with gout could be at a higher risk of developing uric acid kidney stones because they have a higher level of uric acid being excreted by the kidneys, and they have more acidic urine, which makes the uric acid more likely to form stones, according to Michael Toprover, MD, a rheumatologist at NYU Langone Health.

When gout treatment does not reduce levels uric acid enough (or if you have a more serious type of gout), several complications can develop, including uric acid kidney stones, according to the American Kidney Fund.

Other lifestyle factors may also contribute to the risk of developing kidney stones, including a higher intake of sugar-sweetened beverages and being overweight, according to Dr. Toprover says.

How Common Are Gout-Related Kidney Stones?

Gout affects nearly 10 million U.S. adults, according to a 2019 study in the journal Arthritis & Rheumatology. Kidney stones affect roughly 10 percent of U.S. adults, according to a 2018 review published in the Journal of Clinical Urology. But there is limited research on the prevalence of having both gout and kidney stones.

Dr. Toprover cites two main studies that examine the occurrence of the two conditions. The first, a 2015 review of 17 studies that found, overall, 14 percent of patients with gout had kidney stones. A 2019 observational study in Brazil found 35 percent of gout patients had kidney stones.

A 2017 study in Sweden found that the risk of nephrolithiasis (kidney stones) was 60 percent higher in people with gout compared to those without. The researchers also found that being male, obese, and having diabetes increased the risk of those with gout developing kidney stones.

Does Having Kidney Stones Increase Risk of Gout?

Based on limited research, people with kidney stones do not seem to have an increased risk of gout, says Dr. Toprover. This is because most kidney stones are more commonly caused factors that result in a build-up of calcium, not a build-up of uric acid associated with gout.

Are Your Kidney Stones Due to Gout — Or Something Else?

According to the American Urological Foundation, kidney stones can cause severe and sharp pain, specifically in the back and abdomen, as well as while urinating. They could also cause nausea, vomiting, blood in urine, or frequent urination.

These symptoms could point to any of the four types of kidney stones, which are classified based on what they are made of:

  • Calcium
  • Struvite (from bacteria)
  • Cystine (from an amino acid)
  • Uric acid

That said, there are no symptoms that indicate you are experiencing uric acid stones specifically due to gout. They can, however, be a complication you experience after initially showing signs of gout, such as severe pain, redness, and swelling in joints.

Both men and women of any age can develop kidney stones, though uric acid stones are more likely to develop in men (gout is also more common in men).

If you are not prone to gout flares, or have not been diagnosed with gout, your kidney stones may be more likely to be calcium kidney stones or another type of kidney stones than uric acid stones.

Because various types of kidney stones are made of different substances, each type has its own set of risk factors. The National Kidney Foundation notes, for example that hyperparathyroidism is a risk factor for calcium kidney stones. Hyperparathyroidism is a condition in which your parathyroid glands become overactive and release too much parathyroid hormone (PTH), which causes the calcium levels in your blood to rise. A history of urinary tract infections (UTIs) may increase someone’s risk for struvite stones, according to Medscape, because UTIs make your urine more alkaline, which leads to struvite production.

Some general risk factors for kidney stones include:

  • Dehydration
  • Genetics
  • Excessive weight
  • High-protein diet
  • High-salt diet
  • Diabetes
  • High blood sugar
  • High blood pressure
  • Medications like triamterene diuretics, antiseizure drugs, and calcium-based antacids

How Doctors Diagnose Gout-Related Kidney Stones

If you suspect you could have kidney stones related to gout, you should see the doctor who manages your gout, whether that’s a primary care doctor, rheumatologist, or another specialist.

They will take your medical history and do a physical exam. They may also run blood tests, as well as a test to see if your urine is highly acidic, meaning it has a pH level below 5.5. They may also send a passed kidney stone to the lab for analysis to check if it is made of uric acid, according to the Cleveland Clinic.

Treatment for Gout-Related Kidney Stones

Treatment for kidney stones includes getting rid of, or passing, stones you currently have and preventing future stones from developing.

According to the Mayo Clinic, most small kidney stones will pass on their own; drinking plenty of water and taking pain relievers can help. In the case of larger or more invasive stones, other procedures may be needed, including surgery.

Because there is limited research about the cause and treatment of gout-related kidney stones, your doctor may treat each condition separately through lifestyle changes and medications.

Lifestyle Changes

Here are other important lifestyle changes he recommends:

1. Watch what you eat

Avoid eating too many foods high in purines, which the body breaks down into uric acid. These include organ meats such as liver, certain seafood such as shellfish, and red meat, he advises. Soda and other drinks sweetened with high fructose corn syrup, as well as alcohol can also aggravate gout and cause uric acid kidney stones.

2. Stay hydrated

A person with a history of kidney stones should focus on staying hydrated to maintain optimal kidney function. According to Harvard Health, you should aim to drink two liters of water every day (about eight 8-ouce cups).

Dr. Toprover adds that “patients with gout can also benefit from drinking plenty of water to help their kidneys and avoid sugary drinks that could increase their uric acid levels.”

3. Talk to your doctor about your supplements

Some over-the-counter supplements can affect kidney stone formation, so it’s a good idea to review your supplements with your doctor. For example, taking more than 500 mg of vitamin C on a daily basis has been shown to increase the risk of kidney stones. Additionally, creatine has been shown to worsen kidney dysfunction in people with kidney disorders.

Medications

Medication to lower uric acid levels is a key part of treating gout, and in turn, reducing the risk of gout-related kidney stones.

Anti-inflammatory medications, like colchicine, may be used to relieve gout pain and prevent gout attacks. Additionally, medications such as allopurinol or febuxostat may be prescribed to help patients to maintain a safe uric acid level and prevent worsening symptoms, including more advanced gout and uric acid kidney stones.

If you are experiencing kidney stones related to gout, you may need to see a rheumatologist and/or a nephrologist to manage your condition.

  • Nonsteroidal anti-inflammatory drugs (NSAIDs) are often used to relieve pain during gout flares. If, however, you have decreased kidney function, NSAIDs may increase your risk of sudden kidney failure and potentially progressive kidney damage, according to the National Kidney Foundation.
  • Alpha blockers, a type of blood pressure medication, may be prescribed to help patients pass kidney stones. But a 2016 study found that alpha blockers may increase the level of uric acid in patients.

Gout-related kidney stones can signal a more serious form of gout, so it’s important to talk to all of your health care providers to discuss how to best manage your conditions. For example, Dr. Toprover says some patients who still have high uric acid and complications, including uric acid stones, despite taking uric acid lowering medications have achieved lower urate levels and prevented gout flares with a medication called pegloticase. It’s also a good idea to make sure you’re working with your primary care doctor to address other health issues that can affect your gout and kidney health, such as weight, blood pressure, and blood sugar.

Learn More About Living with Gout

Check out The Gout Show, our podcast series hosted by gout patient Steve Clisby. Learn from gout patients and renowned doctors what living with gout is all about—and how to do it better. Listen to The Gout Show here.

Allopurinol (Zyloprim, Aloprim). American College of Rheumatology. https://www.rheumatology.org/I-Am-A/Patient-Caregiver/Treatments/Allopurinol-Zyloprim-Aloprim.

Calcium Oxalate Stones. National Kidney Foundation. https://www.kidney.org/atoz/content/calcium-oxalate-stone.

Chen-Xu M, et al. Contemporary Prevalence of Gout and Hyperuricemia in the United States and Decadal Trends: The National Health and Nutrition Examination Survey, 2007–2016. Arthritis & Rheumatology. January 7, 2019. doi: https://doi.org/10.1002/art.40807.

Chen, Z, et al. Prevalence of kidney stones in the USA: The National Health and Nutrition Evaluation Survey. Journal of Clinical Urology. November 26, 2018. doi: https://doi.org/10.1177/2051415818813820.

Colchicine. Medline Plus. April 15, 2019. https://medlineplus.gov/druginfo/meds/a682711.html.

Complications of Gout. American Kidney Fund. June 16, 2020. https://www.kidneyfund.org/kidney-disease/chronic-kidney-disease-ckd/complications/gout/complications-of-gout/.

Dave CN, et al. What causes struvite stones in nephrolithiasis? Medscape. January 13, 2020. https://www.medscape.com/answers/437096-155522/what-causes-struvite-stones-in-nephrolithiasis.

Febuxostat (Uloric). American College of Rheumatology. https://www.rheumatology.org/I-Am-A/Patient-Caregiver/Treatments/Febuxostat-Uloric.

Gout and Kidney Disease. American Kidney Fund. June 16, 2020. https://www.kidneyfund.org/kidney-disease/chronic-kidney-disease-ckd/complications/gout/gout-and-kidney-disease/.

Hoff LS., et al. Nephrolithiasis in gout: prevalence and characteristics of Brazilian patients. Advances in Rheumatology. December 31, 2019. doi: https://doi.org/10.1186/s42358-019-0106-4.

Howels SA, et al. Genetics of kidney stone disease. Nature Reviews Neurology. June 12, 2020. doi: https://doi.org/10.1038/s41585-020-0332-x.

Interview with Michael Toprover, MD, a rheumatologist at NYU Langone Health.

Kidney Stones. American Urological Association. https://www.urologyhealth.org/urology-a-z/k/kidney-stones.

Kidney Stones. The Mayo Clinic. May 5, 2020. https://www.mayoclinic.org/diseases-conditions/kidney-stones/diagnosis-treatment/drc-20355759.

Kidney Stone. The Urology Care Foundation. https://www.urologyhealth.org/urology-a-z/k/kidney-stones.

Landgren AJ, et al. Incidence of and risk factors for nephrolithiasis in patients with gout and the general population, a cohort study. Arthritis Research and Therapy. July 24, 2017. doi: https://doi.org/10.1186/s13075-017-1376-z.

Pain Medicines (Analgesics). National Kidney Foundation. February 25, 2021. https://www.kidney.org/atoz/content/painmeds_analgesics.

Roughley MJ, et al. Gout and risk of chronic kidney disease and nephrolithiasis: meta-analysis of observational studies. Arthritis Research and Therapy. April 2015. doi: https://doi.org/10.1186/s13075-015-0610-9

Santos-Hoff L, et al. Nephrolithiasis in gout: prevalence and characteristics of Brazilian patients. Advances in Rheumatology. December 31, 2019. doi: https://doi.org/10.1186/s42358-019-0106-4.

Supplements + OTTCs May Hurt Your Kidneys. Cleveland Clinic. December 30, 2019. https://health.clevelandclinic.org/supplements-otcs-may-hurt-kidneys/.

Ueno S, et al. Effect of Antihypertensive Drugs on Uric Acid Metabolism in Patients with Hypertension: Cross-Sectional Cohort Study. Drug Research. December 2016. doi: https://doi.org/ 10.1055/s-0042-113183.

Uric Acid Stones. Cleveland Clinic. November 3, 2016. https://my.clevelandclinic.org/health/diseases/16378-uric-acid-stones.