Your kidneys perform the essential function of filtering the blood. Sometimes, the substances they filter can harden and cause a stone within the kidney or elsewhere along the urinary tract. Here’s what you need to know about kidney stones.
WHAT ARE KIDNEY STONES?
The kidneys are a pair of organs located in the lower back. They process about 200 quarts of blood each day, removing excess water, toxins and other waste material. Urine represents the byproduct of this filtering. The kidneys make urine and send it down the urinary tract for excretion when you urinate.
Occasionally, material within the urine becomes highly concentrated and forms into a hard, solid mass. When this happens, we call it a “stone.” Kidney stones often do not remain within the kidney. Although many people refer to the stones as “kidney” stones, the medical community labels urinary stones based on their location. So, for example, a stone that get lodged in the urinary tract would be called a “urolithiasis.” Lithiasis is the medical term for a urinary tract stone of any kind. Kidney stones may be very small or fairly large. You may pass small kidney stones and not even know it.
WHAT CAUSES KIDNEY STONES?
Kidney stones often are composed of some combination of calcium, phosphorus and oxalate. These substances occur naturally in every person’s urine. Researchers aren’t sure why some of these substances form kidney stones in some people but not in others. Eating certain foods, taking dietary supplements and certain medications can cause kidney stones to form in people who are susceptible. Not drinking enough water also may contribute to stone formation in the kidneys because dehydration causes the urine to become very concentrated.
RISK FACTORS FOR DEVELOPING KIDNEY STONES
Anyone can develop a kidney stone. In fact, kidney stones are one of the most common problems sending people to the emergency room every year. However, some people are more susceptible to developing kidney stones than others. If you have any of these risk factors, you may be more prone to getting a stone in your urinary tract:
- Family history of kidney stones
- Family history of hypercalcemia (excessive concentration of calcium in the urine)
- Use of diuretics (medications to help remove excess water from the body)
- Cystic kidney disease
- Recurrent blockages of the urinary tract
- Excessive use of calcium-based antacids
- Use of the medications indinavir (an HIV drug) or topiramate (an anti-seizure medication)
- Heart disease or cardiovascular diseases
SYMPTOMS OF KIDNEY STONES
Many people develop and eliminate kidney stones without even knowing it. Those people have no symptoms at all. If you have a larger kidney stone, or if you develop multiple stones, you may experience the following symptoms:
- Pain while urinating
- Bright red blood on urination
- Periodic sharp pain in the lower back
- Moderate to severe pain in the lower abdomen
Usually, a kidney stone is not a medical emergency. However, if you find yourself unable to urinate, no matter how hard you try or how long you wait, and if your bladder becomes hard and distended, you should seek emergency medical treatment.
TREATMENT AND PREVENTION OF KIDNEY STONES
The first line treatment for a kidney stone is to drink plenty of water and see if it passes on its own. If it does not, or if you develop multiple stones that may damage the kidneys or block the flow of urine from the bladder, your health care provider may recommend a surgical intervention. Kidney stones are surgically treated using these primary methods (all performed under general anesthesia):
- Ureteroscopy. A urologist inserts a thin, flexible instrument with a camera into the urethra and moves it up the urinary tract to look for stones. If found, these stones can be removed at the same time.
- Shock wave lithotripsy. A patient’s body is subjected to multiple, rapid shockwaves that literally cause the kidney stones to crumble into small pieces. The pieces then can be passed naturally with little discomfort.
- Percutaneous nephrolithotomy. A urologist inserts a probe directly into the kidney(s), through the skin, and delivers direct shock waves to large stones to break them into pieces.
After surgical treatment or in conjunction with it, your health care provider may recommend certain dietary changes and/or medications to help prevent the development of future kidney stones. These preventative treatments are highly correlated to the type of kidney stones you get, such as stones composed of calcium. Note that eating less calcium in your diet will not necessarily reduce your risk of kidney stones and could be harmful to your overall health. If you’re prone to kidney stones, consult your health care provider for instructions on how to prevent them.
LIVING WELL WITH KIDNEY STONES
Urinary stones can be a nuisance, and in severe cases they can cause kidney damage. However, you can live well with kidney stones as long as you follow your health care provider’s instructions for diet and medication. Drink plenty of water and urinate when you feel the urge to go in order to help avoid developing kidney stones in the first place.