Recurring kidney stones — Help!

Dear In pain,

Kidney stones, also known as renal lithiasis, form when minerals and acid salts in the kidneys stick together and solidify, forming a stone that can be as small as a grain of sand or as large as a golf ball. This stone will continue to grow until it leaves the body, either through urine or surgery. While simple lifestyle changes and medicines may help prevent kidney stones from forming, it's a good idea to determine, with the help of a health care provider, why you repeatedly develop kidney stones.

One way to help determine why this keeps happening is to figure out what kind of kidney stones you have. Once you know this, it may be easier to determine the best prevention method. The different types of stones include:

• Calcium stones: These can form in calcium oxalate or calcium phosphate. They can be the result of the consumption of certain foods or through taking certain medications. This is the most common type of kidney stone.
• Struvite stones: These stones can form as the result of an infection. They have the potential to grow quickly and become pretty big, even with few or no symptoms.
• Uric acid stones: These can occur in people who don't drink enough fluid or who lose too much fluid from their bodies. They can also occur in those who consume too much protein or have gout.
• Cystine stones: These can occur in people with cystinuria, which is a genetic disorder that causes the kidneys to excrete too many of certain amino acids.

List adapted from Mayo Clinic.

If you're able, bringing one to your health care provider the next time one passes may help them determine the particular type of stone. In addition, people who’ve had them in the past are 50 percent more likely to develop more kidney stones within five to seven years. Additional risk factors include:

• Not drinking enough water and other fluids
• Family history of kidney stones
• Consuming a high-protein, high-sugar, or high-sodium diet
• Being obese or having a large waist size
• Having certain digestive diseases such as inflammatory bowel disease or chronic diarrhea
• Undergoing gastric bypass surgery
• Other medical conditions including renal tubular acidosis, cystinuria, hyperparathyroidism, certain medications, and some urinary tract infections

You mentioned that you've changed your diet. If you haven't yet, incorporating some of these suggestions may help.

• Drink at least 12 cups of fluids per day — it’s recommended that at least half of these fluids be plain water; if you sweat, then you’ll want to drink more to replenish the water you lost.
• Reduce daily salt intake, not just from potato chips and pretzels, but also from processed foods such as sandwich meat and canned soup.
• Choose non-animal protein sources such as legumes over meat.
• To prevent calcium oxalate stones, reduce intake of foods that are high in oxalates (i.e., beets, rhubarb, okra, sweet potato, spinach, products containing soy, chocolate, and tea).

List adapted from Mayo Clinic and the National Kidney Foundation.

Keep in mind that if your kidney stones are from infections or genetic causes, dietary changes may not affect the development of kidney stones. In any case, if dietary changes continue to be ineffective, it may be worth asking your health care provider about medications that could help prevent kidney stones. Different medications are available to prevent kidney stones based on the kind that you're experiencing. If you feel that your health care provider isn't as helpful as you'd like, it may be worth getting a second opinion. They may be able to provide some insight or offer some new advice or recommendations. For additional information on kidney stones, check out the websites for the National Institute of Diabetes, Digestive, and Kidney Diseases (NIDDK) and the National Kidney Foundation. 

Kidney stones may be painful, but with a little more information, relief may be just a stone's throw away.