How to Prevent and Treat Kidney Stones

Kidney stones are solid, pebble-like crystals that form in the kidney and may become stuck as they pass into or down the ureter (the tube that carries urine from the kidney to the bladder). They can be as small as a grain of sand or as large as a small fist. And, they hurt.

The good news? You can help minimize the chance of recurrence with diet and lifestyle changes and/or medications.

What are the symptoms of kidney stones?

Stones of all sizes can cause symptoms. The hallmark sign of kidney stones is a pain in the flank (around the sides of the body from the upper abdomen to the back), sometimes radiating to the groin.

Additional symptoms may include:

• bloody urine
• decreased kidney function
• recurrent urinary infections

What are kidney stones made of?

There are four main types of kidney stones. Each has different mineral compositions.

• Calcium stones are the most common type of kidney stones. They are created when calcium combines with oxalate or phosphate in the urine.
• Uric acid stones tend to be related to metabolic dysfunction and are associated with obesity and diabetes.
• Struvite stones, made of magnesium and ammonia, are associated with recurrent urinary tract infections.
• Cystine stones, made of an amino acid called cysteine, are rare and have a genetic cause.

What causes kidney stones?

Kidney stones develop when these minerals or salts supersaturate in the urine, leading to kidney crystallization.

Dietary factors

• Dehydration can cause urine to become more concentrated, increasing the risk of urinary tract infections and stone formation.
• Eating a lot of non-dairy animal protein can increase the acidity of the urine and cause both uric acid and calcium stones.
• Diets low in fruits and vegetables can make urine more acidic and decrease citric acid (preventing kidney stones formation). 
• Diets high in salt can increase calcium excretion in the urine, leading to an increased risk of calcium stones. 

Medical causes

• Hyperparathyroidism causes the body to overproduce the parathyroid hormone, which can increase calcium in the blood and urine, raising the risk of calcium kidney stones.
• Malabsorption and intestinal issues can increase oxalate absorption and hypercalciuria and worsen dehydration, raising the risk for kidney stones. 
• The bacteria that cause urinary tract infections can form struvite kidney stones.
• Gout is caused by an excess of uric acid in the blood, which can form kidney stones.
• Hormonal changes during pregnancy can increase the risk of developing kidney stones.
• Taking certain medications or supplements can increase the risk of kidney stones. These include topiramate, loop diuretics, and some antiretroviral medications, as well as vitamin C and D supplements.

How to prevent kidney stones

“If you are prone to kidney stones, the most effective preventative measure is to increase your diet and exercise while maintaining adequate hydration,” says Jonathan Elliott Katz, M.D., a urologist who specializes in endourology and stone disease at the Desai Sethi Urology Institute (DSUI), part of the University of Miami Health System. “For patients who experience recurrent kidney stones, I recommend a 24-hour urine collection. This helps us identify any underlying metabolic abnormalities that contribute to stone formation. Precise recommendations and pharmacological interventions can be tailored based on the results of this urine analysis.”

In addition, “the following general dietary and lifestyle modifications can be beneficial,” Dr. Katz says.  

• Limit high-purine foods. Decrease all non-dairy animal protein, especially red meat, organ meats and shellfish. 
• Reduce sodium intake. Excessive salt can increase urine concentration and increase calcium excretion.
• Stay hydrated. Drink plenty of water to dilute urine.
• Increase fruits and vegetables. This increases potassium, citrate and fiber.
• Consider dietary supplements. In some cases, supplements like magnesium or citrate may be recommended.
• Stay active.

How do you diagnose and treat kidney stones?

Your primary care doctor, an urgent care provider or your urologist will determine if your symptoms are caused by the presence of one or more stones. To confirm the diagnosis, your provider may order a variety of urine and blood tests. They will likely conduct imaging tests (such as ultrasound and x-ray) to determine the location, size and number of the stones.

A computerized tomography (a CT scan) is the most accurate and definitive way to confirm the size, location, and optimal treatment of stones.

Expert urologists at DSUI offer the latest approaches to treat kidney stones and prevent them from recurring. “We tailor our treatment approach based on shared decision-making,” says Dr. Katz.

If you have small kidney stones, you may be able to pass them at home.

However, this can be painful. You can take over-the-counter pain relievers or speak to your healthcare provider for prescription-strength pain medication.

There are a couple of ways to break up larger stones, making them easier to pass or remove with a scope. Extracorporeal shockwave lithotripsy is a noninvasive technique that uses soundwaves to break kidney stones into smaller pieces. Another option is to insert a thin tube with a tiny lens (called a ureteroscope) through your urethra and into your ureter and kidney. This enables the urologist to break up and remove the stones or allow the smaller pieces to pass through the urine.

If they are large, your urologist may recommend you treat kidney stones through a minimally invasive surgery called percutaneous nephrolithotomy. This procedure requires a small incision (about the size of your pinkie finger) in your back and into your kidney, where specialized tools can be used to remove the stones.

“For smaller stones, shockwave or ureteroscopy is usually adequate,” says Dr. Katz. “For larger stones, the more invasive percutaneous procedure is needed. For borderline cases, we discuss whether a more invasive approach with a higher stone-free rate is worth the increased risk for each patient.”

If you are experiencing the symptoms of a kidney stone, seek immediate medical attention to rule out a medical emergency. Leaving kidney stones untreated can cause kidney damage, life-threatening infection and other serious complications.

To treat kidney stones and other urologic concerns, UHealth offers innovative, expert care at the Desai Sethi Urology Institute. Personalized treatment plans are based on the latest research and the least invasive procedures.

To make a urology appointment, call 305-243-4551 (option #1) or request an appointment online.

Dana Kantrowitz is a contributor for UHealth’s news service.

Tags: calcium oxalate stones, Desai Sethi Urology Institute, Dr. Jonathan Katz, drinking enough fluids, healthy kidney, type of stone