CONDITIONS

Kidney Stones

What Is Kidney Stones

Kidney stones (also known as nephrolithiasis or renal lithiasis) are one of the most common disorders of the urinary tract and result in almost three million visits to health care providers and more than half a million emergency room visits a year in the United States. Small and firm, they are formed from deposits of mineral and acid salts that are made in the kidneys. These stones can form for many reasons, but most often occur because your urine has become more concentrated than usual, a condition which makes it easier for minerals within it to crystallize and consolidate. The stones can be so small as to be invisible to the naked eye, or can be as large as a pearl—which can determine whether or not you can pass them without intervention. .“Passing” a kidney stone refers to having it leave your body via your urinary tract. There are several factors that can influence your ability to pass a kidney stone, including how big you are, prior stone passage, prostate enlargement, pregnancy, and the size of the stone Depending on your particular situation, you may only need to drink lots of water and take pain medication to pass a kidney stone. If, however, a kidney stone becomes lodged in your urinary tract or causes other complications, surgery may be necessary. It can be quite painful to pass kidney stones, though they usually cause not permanent damage

In the United States, 1 in 11 people (or 8% of the population) has had a kidney stone at some point. A study that appeared in the journal Urology in 2010 found that the incidence of kidney stones is increasing globally. In the United States, their prevalence has remained fairly steady since the 1980s, but has increased greatly since the 1970s, when the incidence in the USA was less the four percent of the population. Caucasians are more susceptible to developing kidney stones than African Americans, and they occur more frequently in men than in women. Prevalence increases as men pass the age of 40, whereas prevalence peaks for women in their 50s. And if you have had a kidney stone, you are at greater risk of developing others.

What Causes Kidney Stones

Urine naturally contains certain substances that are prone to forming crystals, like uric acid, oxalate (a substance produced by your liver and also found in foods, especially chocolate, nuts, and certain fruits and vegetables), and calcium. Normally, the fluid in your urine is able to dilute them, but when it can’t, stones can develop. Your urine may also not have enough of the substances that discourage calcium formation, another factor favoring the development of kidney stones. There are different kinds of kidney stones, and each forms due to a different set of circumstances:

  • Calcium stones account for the majority of kidney stones, and are usually formed from calcium oxalate. Both calcium and oxalate may become concentrated in your urine due to factors like your diet, high doses of vitamin D, metabolic abnormalities, or intestinal bypass surgery. In addition to calcium oxalate stones, your body may also develop stones made from calcium phosphate.
  • Struvite stones occur from the body’s reaction to infection, such as an infection of the urinary tract. These stones may develop rapidly and grow large.
  • Uric acid stones can form as a result of losing too much fluid, not drinking enough fluid, or as a side effect of having gout. Some people are more likely than others to form these stones, due to their genes.
  • Cystine stones are a hereditary disorder caused when a person’s kidneys excrete abnormally high levels of amino acids.
  • Other stones may occur in rare instances due to a variety of factors.

Risk Factors For Kidney Stones

There are several factors that influence the risk of developing kidney stones. These include:

  • Your personal and family history. If you’ve already had a kidney stone, you’re at increased risk of developing another. Your odds are also greater if someone in your family has had a kidney stone.
  • Dehydration. A lack of fluid in the urine can cause certain substances within it to form crystals and stick together.
  • Your diet. Consuming lots of protein or sugar can lead to kidney stones. Most of all, though, a high-sodium diet puts you at risk: It places a burden on your kidneys by making them filter more calcium.
  • Obesity. Weight gain, a large waist, and a high body-mass index (BMI) are all associated with kidney stones.
  • Digestive diseases. If you suffer from chronic diarrhea or inflammatory bowel disease (IBD),  your body’s ability  to absorb and use both calcium and water may be impacted, increasing your risk of developing kidney stones. These conditions are linked to higher probability of developing kidney stones.
  • Gastric bypass surgery may lead to changes in how your body digests food, ultimately allowing kidney stones to form.
  • Other conditions may also result in kidney stones, including:
    •  Renal tubular acidosis (a disorder in which the kidneys can’t make your urine as acidic as it should be)
    • Hyperparathyroidism (a hormone disorder which causes a loss of calcium)
    • Cystinuria (a rare condition that causes stones made from amino acid to form)
    • Certain medicines

Diagnosing Kidney Stones

Your physician may use any of several diagnostic tests, or a combination of them, to decide if you have kidney stones. These include:

  • Blood tests. Having abnormally high levels of calcium or uric acid in your blood may signal the presence of kidney stones.
  • Urine tests. Your physician may ask you to collect urine samples on two consecutive days, then submit them for testing. If they contain too little of certain substances that prevent stones, or high levels of substances that encourage them, this may be a sign you’ve got kidney stones.
  • Imaging tests such as X-rays of your abdomen or a CT scan can detect the presence of kidney stones.
  • Ultrasounds are noninvasive and may reveal lurking kidney stones.
  • Intravenous urography is a test in which dye is injected to your arm, and then X-ray or CT scan images are taken as the dye makes its way through your kidneys and bladder.
  • Examination of stones you are passing. Your physician may instruct you to urinate into a strainer for a period of time, in order to collect stones you pass. Determining their makeup may pinpoint their cause, and help your doctor come up with a prevention plan for the future.

Symptoms of Kidney Stones

You may have heard people talk about how painful kidney stones are. But at first, you may not even know you have them. It’s only when they shift position inside your bladder, or travel into the ureter—the tube that links your kidney to your bladder—that you may feel any or all of these symptoms:

  • Extreme pain in your side or back, beneath your ribs
  • Pain in your groin and lower abdomen
  • Waves of pain that vary in their severity
  • Painful urination
  • Urine that is brown, pink, or red, and/or is cloudy
  • Urine that smells bad
  • Nausea
  • Vomiting
  • A persistent feeling that you need to urinate
  • Frequent urination
  • Producing diminished amount of urine
  • Fever
  • Chills

Prognosis

Although kidney stones can be very painful, they can usually be removed from the body without causing any lasting problems. But don’t wait to call your physician if you experience symptoms of a kidney stone since stones can cause urinary tract infections, and leaving them untreated can result in kidney scarring or permanent damage. If the cause of your kidney stones isn’t determined and addressed, you also run a higher risk of developing them again.

Living With Kidney Stones

If you have large kidney stones, you may need treatment in a hospital, which may include surgery. But if your kidney stones are small, chances are you will be able to pass them on your own without any invasive treatment. During this time, your physician may advise you to do the following:

  • Urinate into a strainer. Collecting the stones you pass will allow your physician to test them. Once she determines their makeup, she can help come up with a plan to prevent them forming again in the future.
  • Drink 6 to 8 eight-ounce glasses of water daily. This will help you produce lots of urine, and have an easier time passing your kidney stones.
  • Take painkillers—either over-the-counter or prescription ones, or a combination of both kinds. They’ll help you cope with any pain you experience as the kidney stones work their way out of your body.
  • Take medications that break down kidney stones. These can vary by stone type and include water pills (thiazide diuretics), diuretics, phosphate solutions, sodium citrate, sodium bicarbonate, antibiotics, and allopurinol.

Screening

Your doctor typically won’t screen you for kidney stones. But if she recognizes several symptoms of them, she will most likely conduct diagnostic tests to determine whether or not you have them.

Prevention

Certain lifestyle adjustments and medications can help prevent kidney stones:

  • Drink 2 to 3 quarts of water gradually over the course of each day, or even more if you live in a dry, hot climate or you exercise vigorously. As a general rule of thumb, dark, cloudy urine signals that you aren’t getting enough water.
  • Following a diet that’s low in both animal protein and sodium. Consider using salt substitutes and swapping beans or tofu for meat..
  • Cut out the soda and energy drinks.
  • Avoid processed foods.
  • Avoid alcohol.
  • Cut back on foods that contain a lot of oxalate if you have a history of suffering from calcium oxalate stones. This may mean eating less okra, spinach, beets, rhubarb, sweet potatoes, Swiss chard, nuts, chocolate, tea, and soy-based foods.
  • Be cautious about taking calcium supplements. Ask your doctor before you do, since they’ve been linked to an increased incidence of kidney stones. He may advise you against them, or instruct you to take them with meals for better absorption. The calcium that occurs naturally in foods doesn’t raise your risk of kidney stones, though—continue to eat calcium-rich foods unless your doctor warns you not to do so.

Medication And Treatment

If tests reveal your kidney stones are small, you may be able to take certain steps to pass them on your own. But if they are too large to pass, or are causing problems such as urinary tract infections, bleeding, or damage to your kidneys, you may need to undergo one of the following procedures:

  • Extracorporeal shock wave lithotripsy (ESWL) This therapy uses vibrations to break up kidney stones into pieces that are small enough to exit your body through your urine. The procedure can last up to an hour and you may be sedated or given light anesthesia to minimize your discomfort.
  • Percutaneous nephrolithotomy is a surgical procedure, one that’s sometimes done only if EWSL (above) doesn’t work. It involves making a small incision in a patient’s back, then using instruments and a telescope to remove a stone. Patients receive general anesthesia and generally spend one to two days of recovery time in the hospital.
  • Removal of stones with a scope and tools. If a relatively small stone is located in your kidney or ureter (a tube that connects your kidneys to your bladder), your physician my thread a thin tube equipped with a light, —this tube is called a ureteroscope—through your urethra and bladder into your ureter. After the stone is pinpointed, special tools can be used to draw it out or to break it down into even smaller pieces that can be passed through your urine. Your doctor may also insert a small tube called a stent in the ureter to keep down swelling and help you heal more quickly. This type of removal sometimes requires either local or general anesthesia.
  • Parathyroid gland surgery. Your parathyroid glands sit at all four corners of your thyroid, a gland situated slightly below your Adam’s apple. Their function is to produce a substance called parathyroid. When they make too much of this hormone, however, the level of calcium in your blood may rise beyond the normal range, ultimately resulting in calcium kidney stones made from calcium phosphate. Sometimes this is caused by a benign tumor on a parathyroid gland—removing it surgically can halt kidney stone formation. Occasionally, there’s some other medical condition affecting your thyroid, which your physician will diagnose and treat.

Complementary and Alternative Treatment

There are various alternative treatments that have been used to help pass kidney stones naturally. Among them, the most popular and reportedly effective, is a drink made from lemon juice, extra-virgin olive oil, and raw apple cider vinegar, which helps break up the stones and eases their passing.

Some studies have shown that magnesium supplements can help prevent kidney stones, as well as reduce their size for easier passing.

Be sure to talk to your doctor about what is right for you.

When To Contact A Doctor

If you think you may have kidney stones, schedule an appointment with your doctor. He or she will be able to conduct diagnostic tests to determine whether or not kidney stone is the root cause of your problems. Call if you experience any of the following:

  • Severe lower back pain
  • A persistent but vague pain or stomach ache
  • Blood-tinged urine
  • Nausea or vomiting
  • Fever
  • Chills
  • Cloudy or foul-smelling urine

Several types of doctors are able to help with kidney stones:

  • Your primary care physician or internist probably has all the expertise you need if you are having a single instance of developing and passing a kidney stone, without complications.
  • An emergency-room physician will be able to treat you if you are actively passing a stone and the pain is severe.
  • A urologist can help if your stone is stuck or is determined to be endangering the proper function of one of your kidneys.
  • A nephrologist (a physician who specializes in kidney disease) may be able to help you if you have had recurrent kidney stones, form more than one at a time, or you have had only one kidney stone, but it was complicated to treat.

Resources:

For more information on kidney stones, visit:

  • The National Kidney Foundation (www.kidney.org) can provide information about treatment and prevention. Its initiatives include screenings, among other services.
  • The National Endocrine, and Metabolic Diseases Information Service (www.endocrine.niddk.nih.gov) answers questions about kidney stones from the public, publishes informational literature about the condition, and works with other outreach organizations.
  • Urology Care Foundation (www.UrologyHealth.org) raises awareness of kidney stones and advocates for research into their treatment.
  • The National Kidney and Urologic Diseases Information Clearinghouse (www.urologic.niddk.nih.gov), which provides information about the urological system and kidneys and answers questions.

Questions For A Doctor

You may wish to ask your doctor the following:

Questions to ask before or shortly after a diagnosis:

  • Do I have a kidney stone?
  • How large is it?
  • Why type of stone is it?
  • Where is it located?
  • Do I require medication, surgery, or another medical procedure?
  • Are there any generic versions of the medications you are prescribing?
  • Do you recommend I visit any particular websites to learn more about this diagnosis?
  • Do you have any literature about my diagnosis that I can take with me to read?
  • Will I need a follow-up visit?

 

  • Post-treatment questions:
    • How likely am I to develop more stones in the future?
    • Going forward, what’s the best way to prevent more stones?
    • How can I best manage this condition, along with other conditions I may have?
    • Do I have to follow any restrictions in the short-term and/or long-term?
    • Will I need to see a specialist, and will his or her expenses be something that’s covered by insurance?
    • Do I need to schedule a follow-up visit with you?