Uric Acid Nephrolithiasis (Kidney Stones)

Uric acid nephrolithiasis is a type of kidney stone that forms when uric acid crystals build up in your kidneys. Uric acid is a waste product your body makes when it breaks down purines, which are natural substances found in many foods and in your own cells. When uric acid levels get too high or your urine becomes too acidic, these crystals can stick together and form hard stones.

These stones differ from the more common calcium kidney stones. Uric acid stones tend to form when urine pH drops below 5.5, making the environment more acidic. The good news is that uric acid stones can sometimes dissolve with the right treatment, unlike calcium stones which usually need to be passed or removed.

About 5 to 10 percent of all kidney stones are uric acid stones. They are more common in people with gout, diabetes, metabolic syndrome, or those who eat a lot of animal protein. Understanding your uric acid levels through blood testing helps you prevent these stones before they form.

• Severe pain in your side, back, or below your ribs that comes in waves
• Pain that radiates to your lower abdomen and groin
• Pain or burning sensation when you urinate
• Pink, red, or brown urine indicating blood
• Cloudy or foul-smelling urine
• Nausea and vomiting
• Frequent need to urinate
• Urinating small amounts at a time
• Fever and chills if infection is present

Some people have small stones that pass without symptoms. Others may have stones that grow silently until they cause a blockage or severe pain.

Uric acid kidney stones form when your urine contains too much uric acid or becomes too acidic. High-protein diets, especially those rich in red meat, organ meats, and shellfish, increase uric acid production in your body. Chronic diarrhea, certain digestive conditions, and not drinking enough water can make your urine more concentrated and acidic. Genetic factors play a role too, as some people naturally produce more uric acid or have kidneys that struggle to remove it efficiently.

Medical conditions like gout, type 2 diabetes, metabolic syndrome, and obesity significantly raise your risk. Chemotherapy and radiation therapy can temporarily spike uric acid levels as cancer cells break down. Some medications, including certain diuretics and low-dose aspirin, can also increase uric acid levels. Living in hot climates or doing intense physical activity without proper hydration concentrates your urine and creates an environment where stones can form.

Doctors diagnose uric acid kidney stones through a combination of imaging tests and lab work. CT scans or ultrasounds can detect stones in your kidneys or urinary tract. Blood tests measure your serum uric acid levels to assess your risk and guide treatment decisions. Urine tests collected over 24 hours show how much uric acid your body produces and excretes, as well as your urine pH level.

Rite Aid offers serum uric acid testing as part of our flagship health panel at Quest Diagnostics locations nationwide. Regular testing helps you monitor your uric acid levels and catch problems before stones form. If you pass a stone, your doctor may analyze it in a lab to confirm it is made of uric acid rather than calcium or other minerals.

• Drink 2 to 3 liters of water daily to dilute urine and prevent crystal formation
• Reduce intake of high-purine foods like red meat, organ meats, sardines, and shellfish
• Limit alcohol, especially beer, which raises uric acid levels
• Eat more fruits and vegetables to make urine less acidic
• Maintain a healthy weight through balanced nutrition and regular activity
• Take potassium citrate or sodium bicarbonate to make urine more alkaline and dissolve stones
• Use allopurinol or febuxostat medications to lower uric acid production
• Manage underlying conditions like diabetes, gout, and metabolic syndrome
• Work with a doctor for pain management during stone passage
• Consider lithotripsy or surgical removal for large stones that do not dissolve