Kidney stones a summer risk

Dehydration is among the causes of the painful condition

WHO’S AT RISK

It’s common knowledge that the dog days of summer increase everyone’s risk of heat stroke and sunburns, but there’s another hot-weather risk that mostly flies under the radar — kidney stones.

“Kidney stones are a solid concretion of various substances that form in the kidney. In severe cases, kidney stones can cause excruciating pain that some patients describe as worse than labor,” says Mount Sinai’s Dr. Mantu Gupta. “The summer months are prime time for kidney stones because it’s easy to get dehydrated, which ups the risk that a stone will form.”

Kidney stones are exceptionally common, with at least one in 10 Americans expected to develop one in his or her lifetime. “Kidney stones used to be much more common in men than women, by a 2-to-1 ratio,” says Gupta. “Now, women are getting stones with much more frequency, which we suspect is linked to the increase in obesity and diets heavy in fatty foods.”

The cause of kidney stones is multifactorial. “It’s usually a combination of genetic, environmental, personal and medical factors,” says Gupta. “Patients are much more likely to have a kidney stone if they have a relative who had stones, though it’s not strictly an inherited condition.”

Doctors have identified a “stone belt” in the U.S. that stretches from the Southeast to the Southwest. “People there are more likely to have stones, which has partly to do with the environment — factors like how much sun they’re getting, how humid it is, and how hard the water is, whether it’s well water or not,” says Gupta. “It also has to do with behavioral factors, like your state of hydration and nutrition.” Obesity and diabetes also increase risk.

Kidney stones commonly afflict the young. “Many stones occur in patients in their 30s,” says Gupta. “However, we are seeing more and more older people with them, especially women.”

One common misconception is that because much of the stone is made of calcium, patients should cut calcium from their diet. “It may seem counterintuitive, but decreasing calcium intake actually increases production of kidney stones,” says Gupta. “The problem has more to do with the oxalate that binds with calcium than the amount of calcium itself.”

SIGNS AND SYMPTOMS

Kidney stones tend to make their presence felt — in the form of pain. “The number one symptom is severe pain on the side of the body below the rib cage and above the hip bone,” says Gupta. “Other common symptoms include nausea, vomiting, pain in the testicles or groin, frequent and urgent urination, and blood in the urine.”

Nonetheless, kidney stones can be tricky to diagnose. “Stones can mimic many other diseases, like colitis, ovarian and testicular disorders, and urinary tract infections,” says Gupta. “So even though kidney stones are common, people are still frequently misdiagnosed.”

But for the average patient, the pathway to diagnosis is fairly straightforward. “Most patients who have severe kidney stones have enough pain that they end up in the ER, where they are usually diagnosed with a CAT scan,” says Gupta. “ER physicians usually recognize the symptoms right away.” The scan will show exactly where the stone is and whether it’s causing swelling.

TRADITIONAL TREATMENT

Once the diagnosis of a kidney stone is made, multiple levels of intervention are possible. The least invasive treatment is observation, since most patients have stones that are small enough to pass on their own, says Gupta. “If the stone is less than 6 millimeters, then we ask the patient to hydrate, give them analgesics, and put them on medical expulsive therapy — that’s the use of medications to decrease the spasms in the ureter, which allows the stone to pass in less time and with less pain.”

The key factor is the size of the stone. “If the stone is less than 4 millimeters, it can pass 80% of the time, but that number drops to 20%-30% for stones larger than 6 millimeters,” says Gupta. “Patients usually need more aggressive treatment when the stone is too large, there is too much pain, or the kidney is swollen.”

There are three main options for these more severe cases. “The least invasive is shock wave lithotripsy (ESWL), which uses shock waves to cause the stone to vibrate and break into fragments,” says Gupta. “There are also laser procedure options, and minimally invasive surgeries.”

There’s a 50% chance a patient will have another stone within four years, says Gupta. “However, that risk can be mitigated by counseling patients on hydration, nutrition, which foods will help and which will hurt.” Exercise can help patients with diabetes or obesity cut risk.

“Kidney stones is one of the most painful conditions that anyone can have, but there’s a lot we can do to control the pain as well as protect the kidney,” says Gupta. “If left untreated, kidney swelling can lead to a loss of function, but that’s largely a preventable outcome.”

RESEARCH BREAKTHROUGHS

Treatment for kidney stones include lots of high-tech advances, especially with nanotechnology. “We’re using smaller cameras that can get up into the kidney more easily,” says Gupta. “And the instruments that we can put through the scopes have been miniaturized, including baskets and lasers.”

QUESTIONS FOR YOUR DOCTOR

Something we should all ask is, “Am I drinking enough water?” Most adults need about 80 ounces of fluid a day. And anyone who has had a kidney stone should ask, “Am I at risk of developing another kidney stone?” And, “How can I change my diet to cut my risk?”

“We have effective treatments for getting rid of your stone and helping ensure that you don’t develop a second one,” says Gupta.