A kidney stone is a solid piece of material that forms from crystallization of excreted substances in the urine. The stone may remain in the kidney or break loose and travel down the urinary tract. A small stone may pass all of the way out of the body, but a larger stone can get stuck in a ureter, the bladder, or the urethra. This may block the flow of urine and cause great pain.
A kidney stone develops from crystals that separate from urine and build up on the inner surfaces of the kidney. Normally, urine contains chemicals that prevent or inhibit the crystals from forming. However, in some people, stones still form. Crystals that remain small enough will travel through the urinary tract and pass out of the body in the urine without even being noticed.
The following are the most common symptoms of kidney stones. However, each individual may experience symptoms differently. Symptoms may include:
- Extreme, sharp pain in the back or side that will not go away. Changing positions does not help. Pain can come and go.
- Blood in the urine
- Nausea and vomiting
- Cloudy or odorous urine
- Frequent urination
- A burning feeling when you urinate
- Fever and chills
Some kidney stones pass out of the body without any intervention by a doctor. In cases that cause lasting symptoms or other complications, kidney stones may be treated with various techniques, including the following:
- Shock waves or extracorporeal shock wave lithotripsy (ESWL). This treatment uses a machine to send shock waves directly to the kidney stone to break a large stone into smaller stones that will pass through the urinary system. There are two types of shock wave machines: with one machine, the patient sits in a tub of water; with the other, the patient lies on a table.
- A long wire with a camera attached to it is inserted into the patient’s urethra and passed up through the bladder to the ureter where the stone is located. A cage is used to obtain the stone and remove it.
- Tunnel surgery (also called percutaneous nephrolithotomy). A small cut is made in the patient's back and a narrow tunnel is made through the skin to the stone inside the kidney. The surgeon can remove the stone through this tunnel.
- Drink more water. Up to 12 full glasses of water a day can help to flush away the substances that form stones in the kidneys. Ginger ale, lemon-lime sodas, and fruit juices are acceptable.
- Limit coffee, tea and cola to one or two cups a day. The caffeine may cause a rapid loss of fluid.
- Consult your doctor regarding dietary modifications.
- Medications may be prescribed to prevent calcium and uric acid stones from forming.