Kidney stones are caused by hardened minerals in the kidneys or urinary system. In most cases, A decrease in urine volume or increase in the minerals causes kidney stones that form stones in the urine.
About 1 in every 20 people will have a kidney stone in their lifetime. Three times more men will have kidney stones than women and they are more common in Caucasians, African Americans.
In most cases, kidney stones are formed when there is too little fluid intake (from dehydration due to lack of drinking or excess exercise), an overabundance of crystal-forming minerals in the urine, and/or lower-than-normal levels of the chemicals that breakdown these minerals in the urine. The kidney stone will either travel out of the body through the urinary tract or stay in the kidney, bladder, or urethra.
Symptoms of kidney stones
You may not know you have a kidney stone unless it causes pain, is large and blocks the flow of urine, or is being passed. The most common symptom is severe, fluctuating pain in the lower back or side under the ribs. Other symptoms include:
- Bloody or cloudy urine that smells bad
- Nausea and/or vomiting
- Fever and/or chills
- The burning, painful sensation when urinating
If you have symptoms, call your doctor. Taking care of kidney stones early can prevent serious complications, such as chronic kidney disease or, in extreme cases, renal failure that would require dialysis or a kidney transplant to replace the function of the kidneys.
Types of kidney stones and how they are formed
There are four major types of kidney stones:
- Calcium kidney stones are the most common. Calcium stones often occur in people with high levels of vitamin D or overactive parathyroid glands. People with CKD are more likely to get calcium kidney stones.
- Struvite kidney stones typically form after a urinary tract infection. They are more common in women, who tend to have chronic urinary infections more often than men. Struvite stones tend to be jagged or stag-horn-shaped stones and can become large, causing damage to the kidneys.
- Uric acid kidney stones are formed due to too much uric acid in the urine is more common in men. A diet high in protein can contribute to the amount of uric acid in the body. People with gout are at risk for uric acid stones.
- Cystine kidney stones are rare compared to the other types of kidney stones because they are caused by an inherited disease called cystinuria. Most people with this condition are diagnosed at a young age and will be treated for this throughout their lifetime.
Treatment for kidney stones
Determining the type of kidney stone, you have is usually done by evaluating a 24-hour collection of urine, or by examining a stone after it has been passed. There are several methods of renal stone removal; many don’t require surgery. You may even be able to pass a stone by drinking lots of water.
Some of the treatments for kidney stones that are too large to pass, or are causing damage, include:
- Shock waves are sent directly to the kidney stone. Extracorporeal shock wave lithotripsy (ESWL) or sound waves is not an invasive treatment, so it doesn’t require surgery or a hospital stay.
- Nephrolithotomy, or percutaneous (meaning “through the skin”) nephrolithotomy, is when the doctor makes a small incision in your back and removes the kidney stone using a nephroscope.
- Ureteroscopic kidney stone removal is a procedure that uses a scope passed through the bladder to remove a stone that is stuck in the ureter.
Preventing kidney stones
Prevention through lifestyle changes, especially eating and exercise habits can help people avoid kidney stones or prevent them. Drinking about 2 to 3 quarts of water a day is usually recommended for someone with a history of kidney stones (unless on a fluid-restricted diet). Diets low in protein can help reduce the chances of developing some types of kidney stones.
Besides dietary adjustments, your doctor may prescribe medicines that help control the amounts of certain minerals from developing in the urine.
Some people get calcium kidney stones because of the excessive production of hormones by the parathyroid glands. Surgically removing one or more of these glands can stop kidney stones from forming.
If you have kidney stones, you may be at a higher risk for chronic kidney disease. Be sure to talk to your doctor about ways to prevent kidney stones from coming back and how to keep your kidneys healthy.