Understanding Kidney Stones

Kidney stones are a common medical condition that affects millions of people every year. These hard deposits that can form in the kidneys cause severe pain and discomfort as they pass through the urinary tract.

Kidney stones are common, affecting about 10% of people at some point, according to the National Kidney Foundation. Fortunately, there are steps you can take to prevent kidney stones from forming in the first place.

In this article, Franciscan Physician Network family doctor Daniel Hekman, MD, discusses what kidney stones are, how kidney stones form and ways you can reduce your risk of developing them.

What Is A Kidney Stone?

A kidney stone is a hard, solid piece of material that forms in the kidneys from the substances in urine. Kidney stones can vary in size and shape, and can be made up of different materials, such as calcium, oxalate and uric acid.

“A kidney stone is essentially just usually a combination of calcium and some other element,” said Dr. Hekman. “Typically, it is calcium phosphate or calcium oxalate.”

Kidney stones can cause intense pain as they pass through the urinary tract. About 1 in 10 people will develop a kidney stone during their lifetime, with men having a slightly higher risk.

What Are Symptoms Of Kidney Stones?

Severe pain, particularly in your lower back, is a hallmark of kidney stones. Kidney stones blocking the flow of urine often cause sharp or cramping pain that starts in the back or side and moves to the groin.

“You definitely will know when you have one, because they are described as some of the most painful symptoms other than childbirth that patients report,” Dr. Hekman said. “Typically, you'll feel it as the stone leaves your kidney and travels down the tube from the kidney to the bladder. It gets kind of wedged in there, and that triggers those alarming nerve and pain symptoms to your side usually, to that side or your flank. And then as it travels down, you actually kind of feel it in your groin area.”

Other common symptoms of kidney stones include:

• Blood in your urine
• Nausea
• Vomiting
• Fever and chills
• Urine that smells bad or looks cloudy.

What Causes Kidney Stones?

Common causes of kidney stones include:

• Drinking too little water
• Exercise (too much or too little)
• Obesity
• Weight loss surgery
• Eating food with too much salt, sugar or fructose.

Risk for recurring kidney stones

As many as 80% of people who have had a kidney stone will have another in the future.

Contributors to kidney stones returning include:

• Family history
• Underlying kidney disease
• Obesity
• Diabetes
• Dietary choices
• Chronic dehydration
• Inflammatory bowel disease.

What Can I Do At Home For Kidney Stones?

If you suspect you may have a kidney stone, hydrationmay help. Kidney stones are more likely to develop in urine that is highly concentrated, appearing dark yellow instead of clear or light-colored. These stones are formed by crystals and can block the flow of urine as it leaves the kidneys through the tubes that carry urine to the bladder.

“You want to try to increase the flow of urine to help it travel down that tube,” Dr. Hekman said. “You have to drink more water to increase more urine. So, hydration is key. Hydration, hydration, hydration.”

How Are Kidney Stones Diagnosed?

Diagnosing a kidney stone may include a physician’s exam and imaging tests.

“The only way to know for sure if you have a kidney stone, first, we typically check a urine to see if there's typically blood in the urine, basically signs that that stone is kind of rubbing against the ureter, and does put a little blood in your urine that we can see when we test the urine,” Dr. Hekman said. “But the only way to know for sure is to do a CT scan or a CAT scan in the hospital."

How Are Kidney Stones Treated?

The size of the kidney stone or stones will determine the treatment plan. Kidney stones become more difficult to pass as they grow, sending more than a half million people to U.S. emergency rooms for treatment each year, according to the National Kidney Foundation.

“Once we've determined the size, if it's under a centimeter, we should be able to get it out with increased hydration and possibly a medication that opens up that urinary tube, that ureter, and that medication's called Flomax,” Dr. Hekman said.

Larger kidney stones, such as ones larger than a centimeter in size, may need to be referred to a urologist. Treatments in those instances include shock wave lithotripsy, which delivers high-energy sound waves through the skin to break the stone into tiny fragments that can then be more easily passed.

“If absolutely needed, they can do surgery, and even put a stent in there or a plastic tube to keep that ureter open and help the stone drain out,” Dr. Hekman said.

What Puts You At Risk Of Kidney Stones?

Simply stated, your hydration levels can make a difference in whether you develop kidney stones.

“Certainly if you are typically dehydrated or not drinking enough water or drinking too much caffeine, which is kind of a diuretic and can dehydrate you, and I think all of us are guilty of that at times,” Dr. Hekman said.

“Then when you're looking at actual like diet and types of foods, so high sodium, low amounts of actual fruits and vegetables, high non-dairy animal proteins and high reduced sugars, like lots of candy or energy drinks,” Dr. Hekman said. “And then actually, believe it or not, just the right amount of calcium intake, so not too little and not too much.”

What Is Recovery From A Kidney Stone Like?

“Once it does pass, it's almost like having a baby, like there is a significant relief right after that,” Dr. Hekman said. “So if somebody did have what's called lithotripsy or that shock treatment done or had a stent put in for a big kidney stone, there might be more residual pain and bleeding for several days to weeks after. But the ones that are smaller, once you pass them, your pain should be gone.”

How Can We Help Prevent Kidney Stones?

“Do your best to stay hydrated,” Dr. Hekman said. “You know, drinking at least like six to eight ideally 12-ounce bottles of water a day just to keep yourself protected from the buildup of this calcium stones is key. But it does kind of depend on the type of kidney stone. Sometimes they're gout related, that’s called uric acid stones. Sometimes there's a bacterial infection called proteus that makes kidney stones that are unique to itself. But most commonly, these calcium oxalate stones, you prevent them with hydration and healthy diet.”

In addition to staying hydrated, talk to your healthcare provider or registered dietitian about whether these diet changes are right for you:

• Limiting sodium intake. Eating a high-sodium diet increases the amount of calcium in urine.
• Eating calcium-rich foods. A normal amount of calcium in your diet is critical to your body’s calcium regulation. The calcium in food combines with oxalates in the intestines, forcing the oxalates into the feces instead of the urine. That reduces the risk of developing kidney stones.
• Cutting back on animal protein, which can increase your risk of developing stones.
• Eating plenty of fruits and veggies, which can help increase urinary citrate and prevent kidney stones.