The National Institute of Diabetes and Kidney Disease reports that about one million people in the United States are treated for kidney stones each year.
Are they serious? Well, they can be. Kidney stones can cause urinary tract infections and kidney damage if left untreated.
The prevalence rises as we age. For men, the chances increase as they enter their 40s, and continue to rise into their 70s. For women, the chance of kidney stones peaks in their 50s. Like a urinary tract infection, once you’ve had one, you’re more prone to get another. When a person gets more than one stone, other stones are likely to develop. So it’s important to know the causes of kidney stones, the signs, and what you need to do.
What are kidney stones?
Kidney stones (nephrolithiasis) really do look like stones. They can be jagged or smooth, usually brown or yellow in color, and as for size, that varies. They can be the size of a grain of sand or as large as a pearl. Some people compare them to golf balls when they get large. Ouch! Imagine a golf ball lodged inside your urinary tract…
But what are kidney stones, exactly? Hard mineral deposits that form inside your kidneys, in the tube draining urine from the kidney – the ureter – or in the bladder. Most kidney stones, thankfully, are small and pass out with your urine.
However, some stones get stuck, partly block your urine flow, and cause persistent symptoms or problems.
Which brings us back to the kidneys. The kidneys filter your blood, removing excess water and waste chemicals to produce urine, which then exits the body. Urine travels from each kidney down the ureter into the bladder. You feel the urge to urinate and finalize the deal when the bladder is full.
What complicates this natural process is that many waste chemicals are dissolved in the urine. Sometimes, these chemicals form crystals in the urine. The crystals clump together to form a small stone. If it doesn’t pass out of your body, it can get bigger and, as we’ve said, bring on infections and cause damage. That’s why passing kidney stones, once they’ve formed in your body, is key.
Causes of kidney stones
How do they happen and are you at risk? The reason why most kidney stones form isn’t known. How’s that for an answer? Kidney stones often have no definitive, single cause – although several factors may increase your risk.
They’re likely to form when your urine has more crystal-forming substances – like uric acid, calcium, and oxalate – than the fluid in your urine can cope with and dilute properly to flush them out of your system. On the flipside, your urine may be lacking in substances that stop crystals from sticking together.
In most cases, though, the amount of calcium and other chemicals in the urine and blood is normal. What happens is, you’re more likely to form a stone if your urine is concentrated. This can happen if you exercise vigorously, or live or work in a hot climate or environment. The danger here is, you may lose more fluid in sweat and less as urine. One of the greatest risk factors for kidney stones is making less than one liter of urine per day.
Bottom line is: Hydration. You want to stay on top of your fluid intake to keep flushing your system in good order. The best way is your eight to 10 glasses of water a day, with a little lime or lemon to help rid your body of toxins.
Types of kidney stones
Knowing the types of kidney stones is a good primer to protect yourself and reduce your risk:
Calcium: The most common type is calcium stones, usually in the form of calcium oxalate. Oxalate, to explain, is naturally found in food, and some foods are higher in oxalate than others, like some fruit and vegetables, as well as some nuts and chocolate. Diet can play a role here: while these foods are healthy, they can still pose problems if you’re not able to excrete the excess.
Also, high vitamin D, intestinal bypass surgery, and metabolic disorders like obesity and diabetes can increase the concentration of calcium oxalate in your urine.
Uric acid: When you don’t drink enough fluids or when you lose too much fluid, uric acid can pose a problem. This also happens in people who eat a high-protein diet, people with gout, or those going through chemotherapy.
Struvite: Found mostly in women with urinary tract infection, these stones can grow quickly and become large, often with no symptoms or little warning.
Cystine: Very rare. These stones occur in both men and women who have cystinuria, the genetic disorder that causes the kidneys to excrete too much of certain amino acids.
Other: Certain medicines can make you more prone to kidney stones, like “water” pills or diuretics, some chemotherapy medicines, and medications some used for HIV treatment. However, many people safely take these medicines, so speak to your doctor.
Kidney stone signs and symptoms
Common kidney stone symptoms are pain in the side or lower abdomen. For men, the pain can head to the groin area as well. This more severe pain is called renal colic. Other signs of kidney stones are:
- blood in urine
- vomiting or nausea
- foul-smelling or discolored urine.
Kidney stone tests and diagnosis
If you have any of the symptoms, testing for kidney stones starts with a health history and physical exam. Blood tests may be ordered to detect calcium, phosphorus, uric acid, and electrolytes. Your doctor may suggest blood urea nitrogen (BUN) and creatinine to assess kidney functioning, or urinalysis to check for crystals, bacteria, blood, and white blood cells. If you’ve already been through passing kidney stones, it’s common to have the stones examined to determine their type.
Special X-rays or scans of the kidneys and the ureters may be done to detect a stone and to check that a stone is not blocking the flow of your urine.
You may need nothing more than to take pain medication and drink lots of water to pass a kidney stone. But if stones become lodged in the urinary tract or cause further problems, you may require surgery.
So prevention is a good first step. That means, keeping well-hydrated. And people prone to forming the stones – especially the most common calcium oxalate stones – should watch certain foods and limit them. Those high-oxalate foods include rhubarb, spinach, beets, Swiss chard, wheat germ, peanuts, okra, and chocolate.
While these have health-protecting nutrients, you need to cut back if you’re at risk for kidney stones. Just when you thought you were eating the right foods for your health!
When it comes to your diet, everyone can lower their risk of developing kidney stones by drinking water throughout the day, limiting their salt and replacing more of their animal proteins with plant-based proteins. More beans and tofu, please!
Kidney stone treatment options
If kidney stones are small enough, they can easily be passed during urination, thus treatment is not required. To deal with the pain associated with kidney stones, your doctor may prescribe you pain relievers, or if the pain is too intense and is causing nausea, they can administer pain medications intravenously.
If kidney stones are too large, then surgery will be required in order to dissolve or remove them. Surgery options include extracorporeal shock wave lithotripsy (ESWL), ureteroscopy, percutaneous nephrolithotomy (PCNL), and open surgery.
If you’re undertaking these preventative measures and treatments already, you’re in good form to protect yourself from the pain, discomfort, and possible complications of kidney stones.