Kidney Stones

What are kidney stones?

Kidney stones are small, hard crystals or deposits that form inside your kidneys when salts and other minerals in your urine bond together. Stones often vary in shape and size, with some growing to be quite large. Some stones stay in the kidneys causing little to no symptoms, and others may pass through the urinary tract, causing painful symptoms as the deposit moves down the ureter. Some people are able to pass the stone without surgical intervention, but in some cases, surgery to remove the stone may be necessary.

Types of Kidney Stones


Photo courtesy of: National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health

Symptoms of kidney stones

If painful symptoms persist, it’s important to contact your urologist for diagnosis and immediate treatment. When a kidney stone has passed into the urinary tract, symptoms may include:

  • Severe pain, usually located in the side or the back; pain may spread to the abdomen and the groin area as well
  • Urinary symptoms such as painful urination, urinary urge, and frequent need to urinate
  • Blood in the urine and/or foul smelling urine
  • Nausea and/or vomiting
  • Fever if the stone has caused an infection

Who is at risk for developing kidney stones?

While anyone can produce kidney stones, certain people are more at risk for developing stones than others. Causes and risk factors for kidney stones include:

  • A family history of stone disease, especially in first degree relatives
  • Dehydration – lack of fluids can cause salts and other minerals in the urine to stick together to cause kidney stones
  • Certain diets – diets high in protein, salt, oxalates (such as spinach, chocolate, nuts), excess vitamin C or D can increase your risk of developing kidney stones
  • Certain medical conditions – gastric conditions such as inflammatory bowel disease, Crohn’s disease and chronic diarrhea affect the way your body absorbs water and calcium, which increases levels of stone-forming substances in your urine
  • Metabolic diseases (such as hyperparathyroidism or gout)
  • Obesity has been linked to higher incidences of stone formation

Non-surgical options for small kidney stones

Patients with smaller stones are typically able to pass the stones through the urinary tract with the aid of the following:

  • Pain relievers – Your doctor may recommend over the counter pain relievers (ibuprofen, acetaminophen) to relieve some discomfort of passing a small stone
  • Medication – Alpha blockers can help relax the muscles in the ureter, which will help you pass a small stone with less pain
  • Increased fluid intake – Drinking an increased amount of water (up to three quarts) may be recommended to help flush out the stone from the urinary tract

Treatment options for large kidney stones

Some kidney stones are too large to pass through the urinary system and may cause painful symptoms or even urinary tract infections. In this case, your doctor may recommend surgical procedures that include:

  • Percutaneous nephrolithotomy (PCNL) – This highly advanced and innovative surgical procedure removes kidney stones through a small incision in the back. The procedure is performed under general anesthesia in a hospital or surgical center. This procedure may be a preferred method to achieve stone free status for many patients. The procedure has a high post-procedure stone free rate of greater than 90%.
  • Shock wave lithotripsy (ESWL) – An X-ray machine is utilized to locate the stone(s) within the body and shock waves are used to break up the stone(s) into very small particles that can be passed through the urine. This procedure is the least invasive option – there are no incisions and no scopes placed into the patient’s body.  ESWL, however, may not be appropriate for all patients as the shock waves may or may not adequately break up stones in certain cases.
  • Ureteroscopy – A small scope is passed into the body through the urethra without the need for an incision. The scope is then advanced to the stone and a laser is used to break up the stone.  This option is appropriate for nearly all stones; however, with larger stones repeat procedures may be necessary to completely clear the stone.

Whenever possible, your doctor will collect the passed or surgically removed kidney stones to have them analyzed in a lab to determine the type of stones your body has made. This analysis will aid your physician in developing a personalized treatment and prevention plan for the future.